Merging changes from upstream

amazon-kinesis-client-multilang/src/main/java/com/amazonaws/services/kinesis/multilang/MultiLangDaemon.java

@@ -26,7 +26,7 @@ import java.util.concurrent.TimeoutException;
 import lombok.extern.slf4j.Slf4j;
 import software.amazon.kinesis.coordinator.KinesisClientLibConfiguration;
 import software.amazon.kinesis.coordinator.Scheduler;
-import software.amazon.kinesis.processor.IRecordProcessorFactory;
+import software.amazon.kinesis.processor.RecordProcessorFactory;
 
 /**
  * Main app that launches the scheduler that runs the multi-language record processor.
@@ -73,7 +73,7 @@ public class MultiLangDaemon implements Callable<Integer> {
         this(buildWorker(recordProcessorFactory, configuration, workerThreadPool));
     }
 
-    private static Scheduler buildWorker(IRecordProcessorFactory recordProcessorFactory,
+    private static Scheduler buildWorker(RecordProcessorFactory recordProcessorFactory,
             KinesisClientLibConfiguration configuration, ExecutorService workerThreadPool) {
         return null;
     }

amazon-kinesis-client-multilang/src/main/java/com/amazonaws/services/kinesis/multilang/MultiLangRecordProcessor.java

@@ -21,8 +21,8 @@ import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Future;
 
 import software.amazon.kinesis.processor.IRecordProcessorCheckpointer;
-import software.amazon.kinesis.processor.IRecordProcessor;
-import software.amazon.kinesis.processor.IShutdownNotificationAware;
+import software.amazon.kinesis.processor.RecordProcessor;
+import software.amazon.kinesis.processor.ShutdownNotificationAware;
 import software.amazon.kinesis.coordinator.KinesisClientLibConfiguration;
 import software.amazon.kinesis.lifecycle.InitializationInput;
 import software.amazon.kinesis.lifecycle.ProcessRecordsInput;
@@ -39,7 +39,7 @@ import lombok.extern.slf4j.Slf4j;
  * called.
  */
 @Slf4j
-public class MultiLangRecordProcessor implements IRecordProcessor, IShutdownNotificationAware {
+public class MultiLangRecordProcessor implements RecordProcessor, ShutdownNotificationAware {
     private static final int EXIT_VALUE = 1;
 
     /** Whether or not record processor initialization is successful. Defaults to false. */

amazon-kinesis-client-multilang/src/main/java/com/amazonaws/services/kinesis/multilang/MultiLangRecordProcessorFactory.java

@@ -16,8 +16,8 @@ package com.amazonaws.services.kinesis.multilang;
 
 import java.util.concurrent.ExecutorService;
 
-import software.amazon.kinesis.processor.IRecordProcessor;
-import software.amazon.kinesis.processor.IRecordProcessorFactory;
+import software.amazon.kinesis.processor.RecordProcessor;
+import software.amazon.kinesis.processor.RecordProcessorFactory;
 import software.amazon.kinesis.coordinator.KinesisClientLibConfiguration;
 import com.fasterxml.jackson.databind.ObjectMapper;
 
@@ -27,7 +27,7 @@ import lombok.extern.slf4j.Slf4j;
  * Creates {@link MultiLangRecordProcessor}'s.
  */
 @Slf4j
-public class MultiLangRecordProcessorFactory implements IRecordProcessorFactory {
+public class MultiLangRecordProcessorFactory implements RecordProcessorFactory {
     private static final String COMMAND_DELIMETER_REGEX = " +";
 
     private final String command;
@@ -63,7 +63,7 @@ public class MultiLangRecordProcessorFactory implements IRecordProcessorFactory
     }
 
     @Override
-    public IRecordProcessor createProcessor() {
+    public RecordProcessor createProcessor() {
         log.debug("Creating new record processor for client executable: {}", command);
         /*
          * Giving ProcessBuilder the command as an array of Strings allows users to specify command line arguments.

amazon-kinesis-client-multilang/src/test/java/com/amazonaws/services/kinesis/multilang/StreamingRecordProcessorFactoryTest.java

@@ -18,7 +18,7 @@ import software.amazon.kinesis.coordinator.KinesisClientLibConfiguration;
 import org.junit.Assert;
 import org.junit.Test;
 
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.RecordProcessor;
 import org.junit.runner.RunWith;
 import org.mockito.Mock;
 import org.mockito.runners.MockitoJUnitRunner;
@@ -32,7 +32,7 @@ public class StreamingRecordProcessorFactoryTest {
     @Test
     public void createProcessorTest() {
         MultiLangRecordProcessorFactory factory = new MultiLangRecordProcessorFactory("somecommand", null, configuration);
-        IRecordProcessor processor = factory.createProcessor();
+        RecordProcessor processor = factory.createProcessor();
 
         Assert.assertEquals("Should have constructed a StreamingRecordProcessor", MultiLangRecordProcessor.class,
                 processor.getClass());

amazon-kinesis-client/src/main/java/software/amazon/kinesis/checkpoint/Checkpoint.java

@@ -15,12 +15,14 @@
 package software.amazon.kinesis.checkpoint;
 
 import lombok.Data;
+import lombok.experimental.Accessors;
 import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
 
 /**
  * A class encapsulating the 2 pieces of state stored in a checkpoint.
  */
 @Data
+@Accessors(fluent = true)
 public class Checkpoint {
     private final ExtendedSequenceNumber checkpoint;
     private final ExtendedSequenceNumber pendingCheckpoint;

amazon-kinesis-client/src/main/java/software/amazon/kinesis/checkpoint/CheckpointConfig.java

@@ -16,13 +16,15 @@
 package software.amazon.kinesis.checkpoint;
 
 import com.amazonaws.services.dynamodbv2.AmazonDynamoDB;
+
 import lombok.Data;
 import lombok.NonNull;
 import lombok.experimental.Accessors;
-import software.amazon.kinesis.coordinator.RecordProcessorCheckpointer;
 import software.amazon.kinesis.leases.ILeaseManager;
+import software.amazon.kinesis.leases.KinesisClientLease;
 import software.amazon.kinesis.leases.KinesisClientLeaseManager;
-import software.amazon.kinesis.leases.LeaseManagementConfig;
+import software.amazon.kinesis.leases.KinesisClientLibLeaseCoordinator;
+import software.amazon.kinesis.leases.LeaseCoordinator;
 import software.amazon.kinesis.metrics.IMetricsFactory;
 import software.amazon.kinesis.metrics.NullMetricsFactory;
 
@@ -53,7 +55,7 @@ public class CheckpointConfig {
 
     private long failoverTimeMillis = 10000L;
 
-    private ILeaseManager leaseManager;
+    private ILeaseManager<KinesisClientLease> leaseManager;
 
     private int maxLeasesForWorker = Integer.MAX_VALUE;
 
@@ -67,7 +69,9 @@ public class CheckpointConfig {
 
     private long epsilonMillis = 25L;
 
-    public ILeaseManager leaseManager() {
+    private LeaseCoordinator<KinesisClientLease> leaseCoordinator;
+
+    public ILeaseManager<KinesisClientLease> leaseManager() {
         if (leaseManager == null) {
             leaseManager = new KinesisClientLeaseManager(tableName, amazonDynamoDB, consistentReads);
         }
@@ -76,7 +80,14 @@ public class CheckpointConfig {
 
     public CheckpointFactory checkpointFactory() {
         if (checkpointFactory == null) {
-            checkpointFactory = new DynamoDBCheckpointFactory(leaseManager(),
+            checkpointFactory = new DynamoDBCheckpointFactory(leaseCoordinator(), leaseManager(), metricsFactory());
+        }
+        return checkpointFactory;
+    }
+
+    public LeaseCoordinator<KinesisClientLease> leaseCoordinator() {
+        if (leaseCoordinator == null) {
+            leaseCoordinator = new KinesisClientLibLeaseCoordinator(leaseManager(),
                     workerIdentifier(),
                     failoverTimeMillis(),
                     epsilonMillis(),
@@ -85,6 +96,6 @@ public class CheckpointConfig {
                     maxLeaseRenewalThreads(),
                     metricsFactory());
         }
-        return checkpointFactory;
+        return leaseCoordinator;
     }
 }

amazon-kinesis-client/src/main/java/software/amazon/kinesis/checkpoint/CheckpointFactory.java

@@ -16,11 +16,11 @@
 package software.amazon.kinesis.checkpoint;
 
 import software.amazon.kinesis.leases.KinesisClientLibLeaseCoordinator;
-import software.amazon.kinesis.processor.ICheckpoint;
+import software.amazon.kinesis.processor.Checkpointer;
 
 /**
  *
  */
 public interface CheckpointFactory {
-    ICheckpoint createCheckpoint(KinesisClientLibLeaseCoordinator leaseCoordinator);
+    Checkpointer createCheckpoint(KinesisClientLibLeaseCoordinator leaseCoordinator);
 }

amazon-kinesis-client/src/main/java/software/amazon/kinesis/checkpoint/DoesNothingPreparedCheckpointer.java

@@ -48,7 +48,7 @@ public class DoesNothingPreparedCheckpointer implements IPreparedCheckpointer {
      * {@inheritDoc}
      */
     @Override
-    public ExtendedSequenceNumber getPendingCheckpoint() {
+    public ExtendedSequenceNumber pendingCheckpoint() {
         return sequenceNumber;
     }
 

amazon-kinesis-client/src/main/java/software/amazon/kinesis/checkpoint/DynamoDBCheckpointFactory.java

@@ -18,9 +18,10 @@ package software.amazon.kinesis.checkpoint;
 import lombok.Data;
 import lombok.NonNull;
 import software.amazon.kinesis.leases.ILeaseManager;
-import software.amazon.kinesis.leases.KinesisClientLibLeaseCoordinator;
+import software.amazon.kinesis.leases.KinesisClientLease;
+import software.amazon.kinesis.leases.LeaseCoordinator;
 import software.amazon.kinesis.metrics.IMetricsFactory;
-import software.amazon.kinesis.processor.ICheckpoint;
+import software.amazon.kinesis.processor.Checkpointer;
 
 /**
  *
@@ -28,19 +29,15 @@ import software.amazon.kinesis.processor.ICheckpoint;
 @Data
 public class DynamoDBCheckpointFactory implements CheckpointFactory {
     @NonNull
-    private final ILeaseManager leaseManager;
+    private final LeaseCoordinator<KinesisClientLease> leaseLeaseCoordinator;
     @NonNull
-    private final String workerIdentifier;
-    private final long failoverTimeMillis;
-    private final long epsilonMillis;
-    private final int maxLeasesForWorker;
-    private final int maxLeasesToStealAtOneTime;
-    private final int maxLeaseRenewalThreads;
+    private final ILeaseManager<KinesisClientLease> leaseManager;
     @NonNull
     private final IMetricsFactory metricsFactory;
 
     @Override
-    public ICheckpoint createCheckpoint(KinesisClientLibLeaseCoordinator leaseCoordinator) {
-        return leaseCoordinator;
+    public Checkpointer createCheckpoint() {
+        return new DynamoDBCheckpointer(leaseLeaseCoordinator, leaseManager, metricsFactory);
     }
+
 }

amazon-kinesis-client/src/main/java/software/amazon/kinesis/checkpoint/DynamoDBCheckpointer.java

@@ -0,0 +1,146 @@
+/*
+ *  Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ *  Licensed under the Amazon Software License (the "License").
+ *  You may not use this file except in compliance with the License.
+ *  A copy of the License is located at
+ *
+ *  http://aws.amazon.com/asl/
+ *
+ *  or in the "license" file accompanying this file. This file is distributed
+ *  on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ *  express or implied. See the License for the specific language governing
+ *  permissions and limitations under the License.
+ */
+
+package software.amazon.kinesis.checkpoint;
+
+import java.util.Objects;
+import java.util.UUID;
+
+import com.amazonaws.services.kinesis.clientlibrary.exceptions.KinesisClientLibDependencyException;
+import com.amazonaws.services.kinesis.clientlibrary.exceptions.KinesisClientLibException;
+import com.amazonaws.services.kinesis.clientlibrary.exceptions.ShutdownException;
+import com.amazonaws.services.kinesis.clientlibrary.exceptions.ThrottlingException;
+import com.amazonaws.services.kinesis.clientlibrary.exceptions.internal.KinesisClientLibIOException;
+import com.google.common.annotations.VisibleForTesting;
+
+import lombok.NonNull;
+import lombok.RequiredArgsConstructor;
+import lombok.extern.slf4j.Slf4j;
+import software.amazon.kinesis.leases.ILeaseManager;
+import software.amazon.kinesis.leases.KinesisClientLease;
+import software.amazon.kinesis.leases.LeaseCoordinator;
+import software.amazon.kinesis.leases.exceptions.DependencyException;
+import software.amazon.kinesis.leases.exceptions.InvalidStateException;
+import software.amazon.kinesis.leases.exceptions.ProvisionedThroughputException;
+import software.amazon.kinesis.metrics.IMetricsFactory;
+import software.amazon.kinesis.processor.Checkpointer;
+import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
+
+/**
+ *
+ */
+@RequiredArgsConstructor
+@Slf4j
+public class DynamoDBCheckpointer implements Checkpointer {
+    @NonNull
+    private final LeaseCoordinator<KinesisClientLease> leaseCoordinator;
+    @NonNull
+    private final ILeaseManager<KinesisClientLease> leaseManager;
+    @NonNull
+    private final IMetricsFactory metricsFactory;
+
+    @Override
+    public void setCheckpoint(final String shardId, final ExtendedSequenceNumber checkpointValue,
+                              final String concurrencyToken) throws KinesisClientLibException {
+        try {
+            boolean wasSuccessful = setCheckpoint(shardId, checkpointValue, UUID.fromString(concurrencyToken));
+            if (!wasSuccessful) {
+                throw new ShutdownException("Can't update checkpoint - instance doesn't hold the lease for this shard");
+            }
+        } catch (ProvisionedThroughputException e) {
+            throw new ThrottlingException("Got throttled while updating checkpoint.", e);
+        } catch (InvalidStateException e) {
+            String message = "Unable to save checkpoint for shardId " + shardId;
+            log.error(message, e);
+            throw new com.amazonaws.services.kinesis.clientlibrary.exceptions.InvalidStateException(message, e);
+        } catch (DependencyException e) {
+            throw new KinesisClientLibDependencyException("Unable to save checkpoint for shardId " + shardId, e);
+        }
+    }
+
+    @Override
+    public ExtendedSequenceNumber getCheckpoint(final String shardId) throws KinesisClientLibException {
+        try {
+            return leaseManager.getLease(shardId).getCheckpoint();
+        } catch (DependencyException | InvalidStateException | ProvisionedThroughputException e) {
+            String message = "Unable to fetch checkpoint for shardId " + shardId;
+            log.error(message, e);
+            throw new KinesisClientLibIOException(message, e);
+        }
+    }
+
+    @Override
+    public Checkpoint getCheckpointObject(final String shardId) throws KinesisClientLibException {
+        try {
+            KinesisClientLease lease = leaseManager.getLease(shardId);
+            return new Checkpoint(lease.getCheckpoint(), lease.getPendingCheckpoint());
+        } catch (DependencyException | InvalidStateException | ProvisionedThroughputException e) {
+            String message = "Unable to fetch checkpoint for shardId " + shardId;
+            log.error(message, e);
+            throw new KinesisClientLibIOException(message, e);
+        }
+    }
+
+    @Override
+    public void prepareCheckpoint(final String shardId, final ExtendedSequenceNumber pendingCheckpoint,
+                                  final String concurrencyToken) throws KinesisClientLibException {
+        try {
+            boolean wasSuccessful =
+                    prepareCheckpoint(shardId, pendingCheckpoint, UUID.fromString(concurrencyToken));
+            if (!wasSuccessful) {
+                throw new ShutdownException(
+                        "Can't prepare checkpoint - instance doesn't hold the lease for this shard");
+            }
+        } catch (ProvisionedThroughputException e) {
+            throw new ThrottlingException("Got throttled while preparing checkpoint.", e);
+        } catch (InvalidStateException e) {
+            String message = "Unable to prepare checkpoint for shardId " + shardId;
+            log.error(message, e);
+            throw new com.amazonaws.services.kinesis.clientlibrary.exceptions.InvalidStateException(message, e);
+        } catch (DependencyException e) {
+            throw new KinesisClientLibDependencyException("Unable to prepare checkpoint for shardId " + shardId, e);
+        }
+    }
+
+    @VisibleForTesting
+    public boolean setCheckpoint(String shardId, ExtendedSequenceNumber checkpoint, UUID concurrencyToken)
+            throws DependencyException, InvalidStateException, ProvisionedThroughputException {
+        KinesisClientLease lease = leaseCoordinator.getCurrentlyHeldLease(shardId);
+        if (lease == null) {
+            log.info("Worker {} could not update checkpoint for shard {} because it does not hold the lease",
+                    leaseCoordinator.getWorkerIdentifier(), shardId);
+            return false;
+        }
+
+        lease.setCheckpoint(checkpoint);
+        lease.setPendingCheckpoint(null);
+        lease.setOwnerSwitchesSinceCheckpoint(0L);
+
+        return leaseCoordinator.updateLease(lease, concurrencyToken);
+    }
+
+    boolean prepareCheckpoint(String shardId, ExtendedSequenceNumber pendingCheckpoint, UUID concurrencyToken)
+            throws DependencyException, InvalidStateException, ProvisionedThroughputException {
+        KinesisClientLease lease = leaseCoordinator.getCurrentlyHeldLease(shardId);
+        if (lease == null) {
+            log.info("Worker {} could not prepare checkpoint for shard {} because it does not hold the lease",
+                    leaseCoordinator.getWorkerIdentifier(), shardId);
+            return false;
+        }
+
+        lease.setPendingCheckpoint(Objects.requireNonNull(pendingCheckpoint, "pendingCheckpoint should not be null"));
+        return leaseCoordinator.updateLease(lease, concurrencyToken);
+    }
+}

amazon-kinesis-client/src/main/java/software/amazon/kinesis/checkpoint/PreparedCheckpointer.java

@@ -48,7 +48,7 @@ public class PreparedCheckpointer implements IPreparedCheckpointer {
      * {@inheritDoc}
      */
     @Override
-    public ExtendedSequenceNumber getPendingCheckpoint() {
+    public ExtendedSequenceNumber pendingCheckpoint() {
         return pendingCheckpointSequenceNumber;
     }
 

amazon-kinesis-client/src/main/java/software/amazon/kinesis/checkpoint/RecordProcessorCheckpointer.java

@@ -12,7 +12,7 @@
  * express or implied. See the License for the specific language governing
  * permissions and limitations under the License.
  */
-package software.amazon.kinesis.coordinator;
+package software.amazon.kinesis.checkpoint;
 
 import com.amazonaws.services.kinesis.clientlibrary.exceptions.InvalidStateException;
 import com.amazonaws.services.kinesis.clientlibrary.exceptions.KinesisClientLibDependencyException;
@@ -32,7 +32,7 @@ import software.amazon.kinesis.leases.ShardInfo;
 import software.amazon.kinesis.metrics.IMetricsFactory;
 import software.amazon.kinesis.metrics.MetricsHelper;
 import software.amazon.kinesis.metrics.ThreadSafeMetricsDelegatingScope;
-import software.amazon.kinesis.processor.ICheckpoint;
+import software.amazon.kinesis.processor.Checkpointer;
 import software.amazon.kinesis.processor.IPreparedCheckpointer;
 import software.amazon.kinesis.processor.IRecordProcessorCheckpointer;
 import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
@@ -49,7 +49,7 @@ public class RecordProcessorCheckpointer implements IRecordProcessorCheckpointer
     @NonNull
     private final ShardInfo shardInfo;
     @NonNull
-    private final ICheckpoint checkpoint;
+    private final Checkpointer checkpoint;
     @NonNull
     private final IMetricsFactory metricsFactory;
 

amazon-kinesis-client/src/main/java/software/amazon/kinesis/coordinator/CoordinatorFactory.java

@@ -17,10 +17,10 @@ package software.amazon.kinesis.coordinator;
 
 import java.util.concurrent.ExecutorService;
 
-import software.amazon.kinesis.checkpoint.Checkpoint;
+import software.amazon.kinesis.checkpoint.RecordProcessorCheckpointer;
 import software.amazon.kinesis.leases.ShardInfo;
 import software.amazon.kinesis.metrics.IMetricsFactory;
-import software.amazon.kinesis.processor.ICheckpoint;
+import software.amazon.kinesis.processor.Checkpointer;
 
 /**
  *
@@ -32,6 +32,6 @@ public interface CoordinatorFactory {
 
     WorkerStateChangeListener createWorkerStateChangeListener();
 
-    RecordProcessorCheckpointer createRecordProcessorCheckpointer(ShardInfo shardInfo, ICheckpoint checkpoint,
+    RecordProcessorCheckpointer createRecordProcessorCheckpointer(ShardInfo shardInfo, Checkpointer checkpoint,
                                                                   IMetricsFactory metricsFactory);
 }

amazon-kinesis-client/src/main/java/software/amazon/kinesis/coordinator/KinesisClientLibConfiguration.java

@@ -28,6 +28,7 @@ import com.amazonaws.services.kinesis.clientlibrary.lib.worker.InitialPositionIn
 import com.google.common.collect.ImmutableSet;
 
 import lombok.Getter;
+import software.amazon.kinesis.checkpoint.RecordProcessorCheckpointer;
 import software.amazon.kinesis.leases.NoOpShardPrioritization;
 import software.amazon.kinesis.leases.ShardPrioritization;
 import software.amazon.kinesis.lifecycle.ProcessRecordsInput;
@@ -36,7 +37,7 @@ import software.amazon.kinesis.lifecycle.ShardConsumer;
 import software.amazon.kinesis.metrics.IMetricsScope;
 import software.amazon.kinesis.metrics.MetricsHelper;
 import software.amazon.kinesis.metrics.MetricsLevel;
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.RecordProcessor;
 import software.amazon.kinesis.retrieval.DataFetchingStrategy;
 import software.amazon.kinesis.retrieval.RecordsFetcherFactory;
 import software.amazon.kinesis.retrieval.SimpleRecordsFetcherFactory;
@@ -1005,7 +1006,7 @@ public class KinesisClientLibConfiguration {
      * <p>
      * This value is only used when no records are returned; if records are returned, the {@link ProcessTask} will
      * immediately retrieve the next set of records after the call to
-     * {@link IRecordProcessor#processRecords(ProcessRecordsInput)}
+     * {@link RecordProcessor#processRecords(ProcessRecordsInput)}
      * has returned. Setting this value to high may result in the KCL being unable to catch up. If you are changing this
      * value it's recommended that you enable {@link #withCallProcessRecordsEvenForEmptyRecordList(boolean)}, and
      * monitor how far behind the records retrieved are by inspecting

amazon-kinesis-client/src/main/java/software/amazon/kinesis/coordinator/Scheduler.java

@@ -59,8 +59,8 @@ import software.amazon.kinesis.metrics.IMetricsFactory;
 import software.amazon.kinesis.metrics.MetricsCollectingTaskDecorator;
 import software.amazon.kinesis.metrics.MetricsConfig;
 import software.amazon.kinesis.metrics.MetricsLevel;
-import software.amazon.kinesis.processor.ICheckpoint;
-import software.amazon.kinesis.processor.IShutdownNotificationAware;
+import software.amazon.kinesis.processor.Checkpointer;
+import software.amazon.kinesis.processor.ShutdownNotificationAware;
 import software.amazon.kinesis.processor.ProcessorConfig;
 import software.amazon.kinesis.processor.ProcessorFactory;
 import software.amazon.kinesis.retrieval.RetrievalConfig;
@@ -84,7 +84,7 @@ public class Scheduler implements Runnable {
     private final RetrievalConfig retrievalConfig;
 
     private final String applicationName;
-    private final ICheckpoint checkpoint;
+    private final Checkpointer checkpoint;
     private final long idleTimeInMilliseconds;
     // Backoff time when polling to check if application has finished processing
     // parent shards
@@ -320,7 +320,7 @@ public class Scheduler implements Runnable {
 
     /**
      * Requests a graceful shutdown of the worker, notifying record processors, that implement
-     * {@link IShutdownNotificationAware}, of the impending shutdown. This gives the record processor a final chance to
+     * {@link ShutdownNotificationAware}, of the impending shutdown. This gives the record processor a final chance to
      * checkpoint.
      *
      * This will only create a single shutdown future. Additional attempts to start a graceful shutdown will return the

amazon-kinesis-client/src/main/java/software/amazon/kinesis/coordinator/SchedulerCoordinatorFactory.java

@@ -25,10 +25,10 @@ import com.google.common.util.concurrent.ThreadFactoryBuilder;
 
 import lombok.Data;
 import lombok.NonNull;
-import software.amazon.kinesis.checkpoint.Checkpoint;
+import software.amazon.kinesis.checkpoint.RecordProcessorCheckpointer;
 import software.amazon.kinesis.leases.ShardInfo;
 import software.amazon.kinesis.metrics.IMetricsFactory;
-import software.amazon.kinesis.processor.ICheckpoint;
+import software.amazon.kinesis.processor.Checkpointer;
 
 /**
  *
@@ -61,7 +61,7 @@ public class SchedulerCoordinatorFactory implements CoordinatorFactory {
 
     @Override
     public RecordProcessorCheckpointer createRecordProcessorCheckpointer(@NonNull final ShardInfo shardInfo,
-                                                                         @NonNull final ICheckpoint checkpoint,
+                                                                         @NonNull final Checkpointer checkpoint,
                                                                          @NonNull final IMetricsFactory metricsFactory) {
         return new RecordProcessorCheckpointer(shardInfo, checkpoint, metricsFactory);
     }

amazon-kinesis-client/src/main/java/software/amazon/kinesis/leases/DynamoDBLeaseRenewer.java

@@ -0,0 +1,410 @@
+/*
+ *  Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ *  Licensed under the Amazon Software License (the "License").
+ *  You may not use this file except in compliance with the License.
+ *  A copy of the License is located at
+ *
+ *  http://aws.amazon.com/asl/
+ *
+ *  or in the "license" file accompanying this file. This file is distributed
+ *  on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ *  express or implied. See the License for the specific language governing
+ *  permissions and limitations under the License.
+ */
+package software.amazon.kinesis.leases;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+import java.util.UUID;
+import java.util.concurrent.Callable;
+import java.util.concurrent.ConcurrentNavigableMap;
+import java.util.concurrent.ConcurrentSkipListMap;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Future;
+import java.util.concurrent.TimeUnit;
+
+import com.amazonaws.services.cloudwatch.model.StandardUnit;
+import software.amazon.kinesis.leases.exceptions.DependencyException;
+import software.amazon.kinesis.leases.exceptions.InvalidStateException;
+import software.amazon.kinesis.leases.exceptions.ProvisionedThroughputException;
+import software.amazon.kinesis.metrics.MetricsHelper;
+import software.amazon.kinesis.metrics.ThreadSafeMetricsDelegatingScope;
+import software.amazon.kinesis.metrics.IMetricsScope;
+import software.amazon.kinesis.metrics.MetricsLevel;
+
+import lombok.extern.slf4j.Slf4j;
+
+/**
+ * An implementation of ILeaseRenewer that uses DynamoDB via LeaseManager.
+ */
+@Slf4j
+public class LeaseRenewer<T extends Lease> implements ILeaseRenewer<T> {
+    private static final int RENEWAL_RETRIES = 2;
+
+    private final ILeaseManager<T> leaseManager;
+    private final ConcurrentNavigableMap<String, T> ownedLeases = new ConcurrentSkipListMap<String, T>();
+    private final String workerIdentifier;
+    private final long leaseDurationNanos;
+    private final ExecutorService executorService;
+
+    /**
+     * Constructor.
+     * 
+     * @param leaseManager LeaseManager to use
+     * @param workerIdentifier identifier of this worker
+     * @param leaseDurationMillis duration of a lease in milliseconds
+     * @param executorService ExecutorService to use for renewing leases in parallel
+     */
+    public LeaseRenewer(ILeaseManager<T> leaseManager, String workerIdentifier, long leaseDurationMillis,
+            ExecutorService executorService) {
+        this.leaseManager = leaseManager;
+        this.workerIdentifier = workerIdentifier;
+        this.leaseDurationNanos = TimeUnit.MILLISECONDS.toNanos(leaseDurationMillis);
+        this.executorService = executorService;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public void renewLeases() throws DependencyException, InvalidStateException {
+        if (log.isDebugEnabled()) {
+            // Due to the eventually consistent nature of ConcurrentNavigableMap iterators, this log entry may become
+            // inaccurate during iteration.
+            log.debug("Worker {} holding %d leases: {}",
+                    workerIdentifier,
+                    ownedLeases.size(),
+                    ownedLeases);
+        }
+
+        /*
+         * Lease renewals are done in parallel so many leases can be renewed for short lease fail over time
+         * configuration. In this case, metrics scope is also shared across different threads, so scope must be thread
+         * safe.
+         */
+        IMetricsScope renewLeaseTaskMetricsScope = new ThreadSafeMetricsDelegatingScope(
+                MetricsHelper.getMetricsScope());
+
+        /*
+         * We iterate in descending order here so that the synchronized(lease) inside renewLease doesn't "lead" calls
+         * to getCurrentlyHeldLeases. They'll still cross paths, but they won't interleave their executions.
+         */
+        int lostLeases = 0;
+        List<Future<Boolean>> renewLeaseTasks = new ArrayList<Future<Boolean>>();
+        for (T lease : ownedLeases.descendingMap().values()) {
+            renewLeaseTasks.add(executorService.submit(new RenewLeaseTask(lease, renewLeaseTaskMetricsScope)));
+        }
+        int leasesInUnknownState = 0;
+        Exception lastException = null;
+        for (Future<Boolean> renewLeaseTask : renewLeaseTasks) {
+            try {
+                if (!renewLeaseTask.get()) {
+                    lostLeases++;
+                }
+            } catch (InterruptedException e) {
+                log.info("Interrupted while waiting for a lease to renew.");
+                leasesInUnknownState += 1;
+                Thread.currentThread().interrupt();
+            } catch (ExecutionException e) {
+                log.error("Encountered an exception while renewing a lease.", e.getCause());
+                leasesInUnknownState += 1;
+                lastException = e;
+            }
+        }
+
+        renewLeaseTaskMetricsScope.addData(
+                "LostLeases", lostLeases, StandardUnit.Count, MetricsLevel.SUMMARY);
+        renewLeaseTaskMetricsScope.addData(
+                "CurrentLeases", ownedLeases.size(), StandardUnit.Count, MetricsLevel.SUMMARY);
+        if (leasesInUnknownState > 0) {
+            throw new DependencyException(String.format("Encountered an exception while renewing leases. "
+                    + "The number of leases which might not have been renewed is %d",
+                    leasesInUnknownState),
+                    lastException);
+        }
+    }
+
+    private class RenewLeaseTask implements Callable<Boolean> {
+
+        private final T lease;
+        private final IMetricsScope metricsScope;
+
+        public RenewLeaseTask(T lease, IMetricsScope metricsScope) {
+            this.lease = lease;
+            this.metricsScope = metricsScope;
+        }
+
+        @Override
+        public Boolean call() throws Exception {
+            MetricsHelper.setMetricsScope(metricsScope);
+            try {
+                return renewLease(lease);
+            } finally {
+                MetricsHelper.unsetMetricsScope();
+            }
+        }
+    }
+
+    private boolean renewLease(T lease) throws DependencyException, InvalidStateException {
+        return renewLease(lease, false);
+    }
+
+    private boolean renewLease(T lease, boolean renewEvenIfExpired) throws DependencyException, InvalidStateException {
+        String leaseKey = lease.getLeaseKey();
+
+        boolean success = false;
+        boolean renewedLease = false;
+        long startTime = System.currentTimeMillis();
+        try {
+            for (int i = 1; i <= RENEWAL_RETRIES; i++) {
+                try {
+                    synchronized (lease) {
+                        // Don't renew expired lease during regular renewals. getCopyOfHeldLease may have returned null
+                        // triggering the application processing to treat this as a lost lease (fail checkpoint with
+                        // ShutdownException).
+                        boolean isLeaseExpired = lease.isExpired(leaseDurationNanos, System.nanoTime());
+                        if (renewEvenIfExpired || !isLeaseExpired) {
+                            renewedLease = leaseManager.renewLease(lease);
+                        }
+                        if (renewedLease) {
+                            lease.setLastCounterIncrementNanos(System.nanoTime());
+                        }
+                    }
+
+                    if (renewedLease) {
+                        if (log.isDebugEnabled()) {
+                            log.debug("Worker {} successfully renewed lease with key {}",
+                                    workerIdentifier,
+                                    leaseKey);
+                        }
+                    } else {
+                        log.info("Worker {} lost lease with key {}", workerIdentifier, leaseKey);
+                        ownedLeases.remove(leaseKey);
+                    }
+
+                    success = true;
+                    break;
+                } catch (ProvisionedThroughputException e) {
+                    log.info("Worker {} could not renew lease with key {} on try {} out of {} due to capacity",
+                            workerIdentifier,
+                            leaseKey,
+                            i,
+                            RENEWAL_RETRIES);
+                }
+            }
+        } finally {
+            MetricsHelper.addSuccessAndLatency("RenewLease", startTime, success, MetricsLevel.DETAILED);
+        }
+
+        return renewedLease;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public Map<String, T> getCurrentlyHeldLeases() {
+        Map<String, T> result = new HashMap<String, T>();
+        long now = System.nanoTime();
+
+        for (String leaseKey : ownedLeases.keySet()) {
+            T copy = getCopyOfHeldLease(leaseKey, now);
+            if (copy != null) {
+                result.put(copy.getLeaseKey(), copy);
+            }
+        }
+
+        return result;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public T getCurrentlyHeldLease(String leaseKey) {
+        return getCopyOfHeldLease(leaseKey, System.nanoTime());
+    }
+
+    /**
+     * Internal method to return a lease with a specific lease key only if we currently hold it.
+     * 
+     * @param leaseKey key of lease to return
+     * @param now current timestamp for old-ness checking
+     * @return non-authoritative copy of the held lease, or null if we don't currently hold it
+     */
+    private T getCopyOfHeldLease(String leaseKey, long now) {
+        T authoritativeLease = ownedLeases.get(leaseKey);
+        if (authoritativeLease == null) {
+            return null;
+        } else {
+            T copy = null;
+            synchronized (authoritativeLease) {
+                copy = authoritativeLease.copy();
+            }
+
+            if (copy.isExpired(leaseDurationNanos, now)) {
+                log.info("getCurrentlyHeldLease not returning lease with key {} because it is expired",
+                        copy.getLeaseKey());
+                return null;
+            } else {
+                return copy;
+            }
+        }
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public boolean updateLease(T lease, UUID concurrencyToken)
+        throws DependencyException, InvalidStateException, ProvisionedThroughputException {
+        verifyNotNull(lease, "lease cannot be null");
+        verifyNotNull(lease.getLeaseKey(), "leaseKey cannot be null");
+        verifyNotNull(concurrencyToken, "concurrencyToken cannot be null");
+
+        String leaseKey = lease.getLeaseKey();
+        T authoritativeLease = ownedLeases.get(leaseKey);
+
+        if (authoritativeLease == null) {
+            log.info("Worker {} could not update lease with key {} because it does not hold it",
+                    workerIdentifier,
+                    leaseKey);
+            return false;
+        }
+
+        /*
+         * If the passed-in concurrency token doesn't match the concurrency token of the authoritative lease, it means
+         * the lease was lost and regained between when the caller acquired his concurrency token and when the caller
+         * called update.
+         */
+        if (!authoritativeLease.getConcurrencyToken().equals(concurrencyToken)) {
+            log.info("Worker {} refusing to update lease with key {} because"
+                    + " concurrency tokens don't match", workerIdentifier, leaseKey);
+            return false;
+        }
+
+        long startTime = System.currentTimeMillis();
+        boolean success = false;
+        try {
+            synchronized (authoritativeLease) {
+                authoritativeLease.update(lease);
+                boolean updatedLease = leaseManager.updateLease(authoritativeLease);
+                if (updatedLease) {
+                    // Updates increment the counter
+                    authoritativeLease.setLastCounterIncrementNanos(System.nanoTime());
+                } else {
+                    /*
+                     * If updateLease returns false, it means someone took the lease from us. Remove the lease
+                     * from our set of owned leases pro-actively rather than waiting for a run of renewLeases().
+                     */
+                    log.info("Worker {} lost lease with key {} - discovered during update",
+                            workerIdentifier,
+                            leaseKey);
+
+                    /*
+                     * Remove only if the value currently in the map is the same as the authoritative lease. We're
+                     * guarding against a pause after the concurrency token check above. It plays out like so:
+                     * 
+                     * 1) Concurrency token check passes
+                     * 2) Pause. Lose lease, re-acquire lease. This requires at least one lease counter update.
+                     * 3) Unpause. leaseManager.updateLease fails conditional write due to counter updates, returns
+                     * false.
+                     * 4) ownedLeases.remove(key, value) doesn't do anything because authoritativeLease does not
+                     * .equals() the re-acquired version in the map on the basis of lease counter. This is what we want.
+                     * If we just used ownedLease.remove(key), we would have pro-actively removed a lease incorrectly.
+                     * 
+                     * Note that there is a subtlety here - Lease.equals() deliberately does not check the concurrency
+                     * token, but it does check the lease counter, so this scheme works.
+                     */
+                    ownedLeases.remove(leaseKey, authoritativeLease);
+                }
+
+                success = true;
+                return updatedLease;
+            }
+        } finally {
+            MetricsHelper.addSuccessAndLatency("UpdateLease", startTime, success, MetricsLevel.DETAILED);
+        }
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public void addLeasesToRenew(Collection<T> newLeases) {
+        verifyNotNull(newLeases, "newLeases cannot be null");
+
+        for (T lease : newLeases) {
+            if (lease.getLastCounterIncrementNanos() == null) {
+                log.info("addLeasesToRenew ignoring lease with key {} because it does not have lastRenewalNanos set",
+                        lease.getLeaseKey());
+                continue;
+            }
+
+            T authoritativeLease = lease.copy();
+
+            /*
+             * Assign a concurrency token when we add this to the set of currently owned leases. This ensures that
+             * every time we acquire a lease, it gets a new concurrency token.
+             */
+            authoritativeLease.setConcurrencyToken(UUID.randomUUID());
+            ownedLeases.put(authoritativeLease.getLeaseKey(), authoritativeLease);
+        }
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public void clearCurrentlyHeldLeases() {
+        ownedLeases.clear();
+    }
+
+    /**
+     * {@inheritDoc}
+     * @param lease the lease to drop.
+     */
+    @Override
+    public void dropLease(T lease) {
+        ownedLeases.remove(lease.getLeaseKey());
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public void initialize() throws DependencyException, InvalidStateException, ProvisionedThroughputException {
+        Collection<T> leases = leaseManager.listLeases();
+        List<T> myLeases = new LinkedList<T>();
+        boolean renewEvenIfExpired = true;
+
+        for (T lease : leases) {
+            if (workerIdentifier.equals(lease.getLeaseOwner())) {
+                log.info(" Worker {} found lease {}", workerIdentifier, lease);
+                // Okay to renew even if lease is expired, because we start with an empty list and we add the lease to
+                // our list only after a successful renew. So we don't need to worry about the edge case where we could
+                // continue renewing a lease after signaling a lease loss to the application.
+                if (renewLease(lease, renewEvenIfExpired)) {
+                    myLeases.add(lease);
+                }
+            } else {
+                log.debug("Worker {} ignoring lease {} ", workerIdentifier, lease);
+            }
+        }
+
+        addLeasesToRenew(myLeases);
+    }
+
+    private void verifyNotNull(Object object, String message) {
+        if (object == null) {
+            throw new IllegalArgumentException(message);
+        }
+    }
+
+}

amazon-kinesis-client/src/main/java/software/amazon/kinesis/leases/DynamoDBLeaseTaker.java

@@ -0,0 +1,535 @@
+/*
+ *  Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ *  Licensed under the Amazon Software License (the "License").
+ *  You may not use this file except in compliance with the License.
+ *  A copy of the License is located at
+ *
+ *  http://aws.amazon.com/asl/
+ *
+ *  or in the "license" file accompanying this file. This file is distributed
+ *  on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ *  express or implied. See the License for the specific language governing
+ *  permissions and limitations under the License.
+ */
+package software.amazon.kinesis.leases;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
+import java.util.concurrent.Callable;
+import java.util.concurrent.TimeUnit;
+
+import com.amazonaws.services.cloudwatch.model.StandardUnit;
+import software.amazon.kinesis.leases.exceptions.DependencyException;
+import software.amazon.kinesis.leases.exceptions.InvalidStateException;
+import software.amazon.kinesis.leases.exceptions.ProvisionedThroughputException;
+import software.amazon.kinesis.metrics.MetricsHelper;
+import software.amazon.kinesis.metrics.IMetricsScope;
+import software.amazon.kinesis.metrics.MetricsLevel;
+
+import lombok.extern.slf4j.Slf4j;
+
+/**
+ * An implementation of ILeaseTaker that uses DynamoDB via LeaseManager.
+ */
+@Slf4j
+public class DynamoDBLeaseTaker<T extends Lease> implements LeaseTaker<T> {
+    private static final int TAKE_RETRIES = 3;
+    private static final int SCAN_RETRIES = 1;
+
+    // See note on takeLeases(Callable) for why we have this callable.
+    private static final Callable<Long> SYSTEM_CLOCK_CALLABLE = new Callable<Long>() {
+
+        @Override
+        public Long call() {
+            return System.nanoTime();
+        }
+    };
+
+    private final ILeaseManager<T> leaseManager;
+    private final String workerIdentifier;
+    private final Map<String, T> allLeases = new HashMap<String, T>();
+    private final long leaseDurationNanos;
+    private int maxLeasesForWorker = Integer.MAX_VALUE;
+    private int maxLeasesToStealAtOneTime = 1;
+
+    private long lastScanTimeNanos = 0L;
+
+    public DynamoDBLeaseTaker(ILeaseManager<T> leaseManager, String workerIdentifier, long leaseDurationMillis) {
+        this.leaseManager = leaseManager;
+        this.workerIdentifier = workerIdentifier;
+        this.leaseDurationNanos = TimeUnit.MILLISECONDS.toNanos(leaseDurationMillis);
+    }
+
+    /**
+     * Worker will not acquire more than the specified max number of leases even if there are more
+     * shards that need to be processed. This can be used in scenarios where a worker is resource constrained or
+     * to prevent lease thrashing when small number of workers pick up all leases for small amount of time during
+     * deployment.
+     * Note that setting a low value may cause data loss (e.g. if there aren't enough Workers to make progress on all
+     * shards). When setting the value for this property, one must ensure enough workers are present to process
+     * shards and should consider future resharding, child shards that may be blocked on parent shards, some workers
+     * becoming unhealthy, etc.
+     *
+     * @param maxLeasesForWorker Max leases this Worker can handle at a time
+     * @return LeaseTaker
+     */
+    public DynamoDBLeaseTaker<T> withMaxLeasesForWorker(int maxLeasesForWorker) {
+        if (maxLeasesForWorker <= 0) {
+            throw new IllegalArgumentException("maxLeasesForWorker should be >= 1");
+        }
+        this.maxLeasesForWorker = maxLeasesForWorker;
+        return this;
+    }
+
+    /**
+     * Max leases to steal from a more loaded Worker at one time (for load balancing).
+     * Setting this to a higher number can allow for faster load convergence (e.g. during deployments, cold starts),
+     * but can cause higher churn in the system.
+     *
+     * @param maxLeasesToStealAtOneTime Steal up to this many leases at one time (for load balancing)
+     * @return LeaseTaker
+     */
+    public DynamoDBLeaseTaker<T> withMaxLeasesToStealAtOneTime(int maxLeasesToStealAtOneTime) {
+        if (maxLeasesToStealAtOneTime <= 0) {
+            throw new IllegalArgumentException("maxLeasesToStealAtOneTime should be >= 1");
+        }
+        this.maxLeasesToStealAtOneTime = maxLeasesToStealAtOneTime;
+        return this;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public Map<String, T> takeLeases() throws DependencyException, InvalidStateException {
+        return takeLeases(SYSTEM_CLOCK_CALLABLE);
+    }
+
+    /**
+     * Internal implementation of takeLeases. Takes a callable that can provide the time to enable test cases without
+     * Thread.sleep. Takes a callable instead of a raw time value because the time needs to be computed as-of
+     * immediately after the scan.
+     * 
+     * @param timeProvider Callable that will supply the time
+     * 
+     * @return map of lease key to taken lease
+     * 
+     * @throws DependencyException
+     * @throws InvalidStateException
+     */
+    synchronized Map<String, T> takeLeases(Callable<Long> timeProvider)
+        throws DependencyException, InvalidStateException {
+        // Key is leaseKey
+        Map<String, T> takenLeases = new HashMap<String, T>();
+
+        long startTime = System.currentTimeMillis();
+        boolean success = false;
+
+        ProvisionedThroughputException lastException = null;
+
+        try {
+            for (int i = 1; i <= SCAN_RETRIES; i++) {
+                try {
+                    updateAllLeases(timeProvider);
+                    success = true;
+                } catch (ProvisionedThroughputException e) {
+                    log.info("Worker {} could not find expired leases on try {} out of {}",
+                            workerIdentifier,
+                            i,
+                            TAKE_RETRIES);
+                    lastException = e;
+                }
+            }
+        } finally {
+            MetricsHelper.addSuccessAndLatency("ListLeases", startTime, success, MetricsLevel.DETAILED);
+        }
+
+        if (lastException != null) {
+            log.error("Worker {} could not scan leases table, aborting takeLeases. Exception caught by last retry:",
+                    workerIdentifier,
+                    lastException);
+            return takenLeases;
+        }
+
+        List<T> expiredLeases = getExpiredLeases();
+
+        Set<T> leasesToTake = computeLeasesToTake(expiredLeases);
+        Set<String> untakenLeaseKeys = new HashSet<String>();
+
+        for (T lease : leasesToTake) {
+            String leaseKey = lease.getLeaseKey();
+
+            startTime = System.currentTimeMillis();
+            success = false;
+            try {
+                for (int i = 1; i <= TAKE_RETRIES; i++) {
+                    try {
+                        if (leaseManager.takeLease(lease, workerIdentifier)) {
+                            lease.setLastCounterIncrementNanos(System.nanoTime());
+                            takenLeases.put(leaseKey, lease);
+                        } else {
+                            untakenLeaseKeys.add(leaseKey);
+                        }
+
+                        success = true;
+                        break;
+                    } catch (ProvisionedThroughputException e) {
+                        log.info("Could not take lease with key {} for worker {} on try {} out of {} due to capacity",
+                                leaseKey,
+                                workerIdentifier,
+                                i,
+                                TAKE_RETRIES);
+                    }
+                }
+            } finally {
+                MetricsHelper.addSuccessAndLatency("TakeLease", startTime, success, MetricsLevel.DETAILED);
+            }
+        }
+
+        if (takenLeases.size() > 0) {
+            log.info("Worker {} successfully took {} leases: {}",
+                    workerIdentifier,
+                    takenLeases.size(),
+                    stringJoin(takenLeases.keySet(), ", "));
+        }
+
+        if (untakenLeaseKeys.size() > 0) {
+            log.info("Worker {} failed to take {} leases: {}",
+                    workerIdentifier,
+                    untakenLeaseKeys.size(),
+                    stringJoin(untakenLeaseKeys, ", "));
+        }
+
+        MetricsHelper.getMetricsScope().addData(
+                "TakenLeases", takenLeases.size(), StandardUnit.Count, MetricsLevel.SUMMARY);
+
+        return takenLeases;
+    }
+
+    /** Package access for testing purposes.
+     *
+     * @param strings
+     * @param delimiter
+     * @return Joined string.
+     */
+    static String stringJoin(Collection<String> strings, String delimiter) {
+        StringBuilder builder = new StringBuilder();
+        boolean needDelimiter = false;
+        for (String string : strings) {
+            if (needDelimiter) {
+                builder.append(delimiter);
+            }
+            builder.append(string);
+            needDelimiter = true;
+        }
+        
+        return builder.toString();
+    }
+
+    /**
+     * Scan all leases and update lastRenewalTime. Add new leases and delete old leases.
+     * 
+     * @param timeProvider callable that supplies the current time
+     * 
+     * @return list of expired leases, possibly empty, never null.
+     * 
+     * @throws ProvisionedThroughputException if listLeases fails due to lack of provisioned throughput
+     * @throws InvalidStateException if the lease table does not exist
+     * @throws DependencyException if listLeases fails in an unexpected way
+     */
+    private void updateAllLeases(Callable<Long> timeProvider)
+        throws DependencyException, InvalidStateException, ProvisionedThroughputException {
+        List<T> freshList = leaseManager.listLeases();
+        try {
+            lastScanTimeNanos = timeProvider.call();
+        } catch (Exception e) {
+            throw new DependencyException("Exception caught from timeProvider", e);
+        }
+
+        // This set will hold the lease keys not updated by the previous listLeases call.
+        Set<String> notUpdated = new HashSet<String>(allLeases.keySet());
+
+        // Iterate over all leases, finding ones to try to acquire that haven't changed since the last iteration
+        for (T lease : freshList) {
+            String leaseKey = lease.getLeaseKey();
+
+            T oldLease = allLeases.get(leaseKey);
+            allLeases.put(leaseKey, lease);
+            notUpdated.remove(leaseKey);
+
+            if (oldLease != null) {
+                // If we've seen this lease before...
+                if (oldLease.getLeaseCounter().equals(lease.getLeaseCounter())) {
+                    // ...and the counter hasn't changed, propagate the lastRenewalNanos time from the old lease
+                    lease.setLastCounterIncrementNanos(oldLease.getLastCounterIncrementNanos());
+                } else {
+                    // ...and the counter has changed, set lastRenewalNanos to the time of the scan.
+                    lease.setLastCounterIncrementNanos(lastScanTimeNanos);
+                }
+            } else {
+                if (lease.getLeaseOwner() == null) {
+                    // if this new lease is unowned, it's never been renewed.
+                    lease.setLastCounterIncrementNanos(0L);
+
+                    if (log.isDebugEnabled()) {
+                        log.debug("Treating new lease with key {} as never renewed because it is new and unowned.",
+                                leaseKey);
+                    }
+                } else {
+                    // if this new lease is owned, treat it as renewed as of the scan
+                    lease.setLastCounterIncrementNanos(lastScanTimeNanos);
+                    if (log.isDebugEnabled()) {
+                        log.debug("Treating new lease with key {} as recently renewed because it is new and owned.",
+                                leaseKey);
+                    }
+                }
+            }
+        }
+
+        // Remove dead leases from allLeases
+        for (String key : notUpdated) {
+            allLeases.remove(key);
+        }
+    }
+
+    /**
+     * @return list of leases that were expired as of our last scan.
+     */
+    private List<T> getExpiredLeases() {
+        List<T> expiredLeases = new ArrayList<T>();
+
+        for (T lease : allLeases.values()) {
+            if (lease.isExpired(leaseDurationNanos, lastScanTimeNanos)) {
+                expiredLeases.add(lease);
+            }
+        }
+
+        return expiredLeases;
+    }
+
+    /**
+     * Compute the number of leases I should try to take based on the state of the system.
+     * 
+     * @param allLeases map of shardId to lease containing all leases
+     * @param expiredLeases list of leases we determined to be expired
+     * @return set of leases to take.
+     */
+    private Set<T> computeLeasesToTake(List<T> expiredLeases) {
+        Map<String, Integer> leaseCounts = computeLeaseCounts(expiredLeases);
+        Set<T> leasesToTake = new HashSet<T>();
+        IMetricsScope metrics = MetricsHelper.getMetricsScope();
+
+        int numLeases = allLeases.size();
+        int numWorkers = leaseCounts.size();
+
+        if (numLeases == 0) {
+            // If there are no leases, I shouldn't try to take any.
+            return leasesToTake;
+        }
+
+        int target;
+        if (numWorkers >= numLeases) {
+            // If we have n leases and n or more workers, each worker can have up to 1 lease, including myself.
+            target = 1;
+        } else {
+            /*
+             * numWorkers must be < numLeases.
+             * 
+             * Our target for each worker is numLeases / numWorkers (+1 if numWorkers doesn't evenly divide numLeases)
+             */
+            target = numLeases / numWorkers + (numLeases % numWorkers == 0 ? 0 : 1);
+
+            // Spill over is the number of leases this worker should have claimed, but did not because it would
+            // exceed the max allowed for this worker.
+            int leaseSpillover = Math.max(0, target - maxLeasesForWorker);
+            if (target > maxLeasesForWorker) {
+                log.warn("Worker {} target is {} leases and maxLeasesForWorker is {}."
+                        + " Resetting target to {}, lease spillover is {}. "
+                        + " Note that some shards may not be processed if no other workers are able to pick them up.",
+                        workerIdentifier,
+                        target,
+                        maxLeasesForWorker,
+                        maxLeasesForWorker,
+                        leaseSpillover);
+                target = maxLeasesForWorker;
+            }
+            metrics.addData("LeaseSpillover", leaseSpillover, StandardUnit.Count, MetricsLevel.SUMMARY);
+        }
+
+        int myCount = leaseCounts.get(workerIdentifier);
+        int numLeasesToReachTarget = target - myCount;
+
+        if (numLeasesToReachTarget <= 0) {
+            // If we don't need anything, return the empty set.
+            return leasesToTake;
+        }
+
+        // Shuffle expiredLeases so workers don't all try to contend for the same leases.
+        Collections.shuffle(expiredLeases);
+
+        int originalExpiredLeasesSize = expiredLeases.size();
+        if (expiredLeases.size() > 0) {
+            // If we have expired leases, get up to <needed> leases from expiredLeases
+            for (; numLeasesToReachTarget > 0 && expiredLeases.size() > 0; numLeasesToReachTarget--) {
+                leasesToTake.add(expiredLeases.remove(0));
+            }
+        } else {
+            // If there are no expired leases and we need a lease, consider stealing.
+            List<T> leasesToSteal = chooseLeasesToSteal(leaseCounts, numLeasesToReachTarget, target);
+            for (T leaseToSteal : leasesToSteal) {
+                log.info("Worker {} needed {} leases but none were expired, so it will steal lease {} from {}",
+                        workerIdentifier,
+                        numLeasesToReachTarget,
+                        leaseToSteal.getLeaseKey(),
+                        leaseToSteal.getLeaseOwner());
+                leasesToTake.add(leaseToSteal);
+            }
+        }
+
+        if (!leasesToTake.isEmpty()) {
+            log.info("Worker {} saw {} total leases, {} available leases, {} "
+                    + "workers. Target is {} leases, I have {} leases, I will take {} leases",
+                    workerIdentifier,
+                    numLeases,
+                    originalExpiredLeasesSize,
+                    numWorkers,
+                    target,
+                    myCount,
+                    leasesToTake.size());
+        }
+
+        metrics.addData("TotalLeases", numLeases, StandardUnit.Count, MetricsLevel.DETAILED);
+        metrics.addData("ExpiredLeases", originalExpiredLeasesSize, StandardUnit.Count, MetricsLevel.SUMMARY);
+        metrics.addData("NumWorkers", numWorkers, StandardUnit.Count, MetricsLevel.SUMMARY);
+        metrics.addData("NeededLeases", numLeasesToReachTarget, StandardUnit.Count, MetricsLevel.DETAILED);
+        metrics.addData("LeasesToTake", leasesToTake.size(), StandardUnit.Count, MetricsLevel.DETAILED);
+
+        return leasesToTake;
+    }
+
+    /**
+     * Choose leases to steal by randomly selecting one or more (up to max) from the most loaded worker.
+     * Stealing rules:
+     * 
+     * Steal up to maxLeasesToStealAtOneTime leases from the most loaded worker if
+     * a) he has > target leases and I need >= 1 leases : steal min(leases needed, maxLeasesToStealAtOneTime)
+     * b) he has == target leases and I need > 1 leases : steal 1
+     * 
+     * @param leaseCounts map of workerIdentifier to lease count
+     * @param needed # of leases needed to reach the target leases for the worker
+     * @param target target # of leases per worker
+     * @return Leases to steal, or empty list if we should not steal
+     */
+    private List<T> chooseLeasesToSteal(Map<String, Integer> leaseCounts, int needed, int target) {
+        List<T> leasesToSteal = new ArrayList<>();
+
+        Entry<String, Integer> mostLoadedWorker = null;
+        // Find the most loaded worker
+        for (Entry<String, Integer> worker : leaseCounts.entrySet()) {
+            if (mostLoadedWorker == null || mostLoadedWorker.getValue() < worker.getValue()) {
+                mostLoadedWorker = worker;
+            }
+        }
+
+        int numLeasesToSteal = 0;
+        if ((mostLoadedWorker.getValue() >= target) && (needed > 0)) {
+            int leasesOverTarget = mostLoadedWorker.getValue() - target;
+            numLeasesToSteal = Math.min(needed, leasesOverTarget);
+            // steal 1 if we need > 1 and max loaded worker has target leases.
+            if ((needed > 1) && (numLeasesToSteal == 0)) {
+                numLeasesToSteal = 1;
+            }
+            numLeasesToSteal = Math.min(numLeasesToSteal, maxLeasesToStealAtOneTime);
+        }
+
+        if (numLeasesToSteal <= 0) {
+            if (log.isDebugEnabled()) {
+                log.debug(String.format("Worker %s not stealing from most loaded worker %s.  He has %d,"
+                        + " target is %d, and I need %d",
+                        workerIdentifier,
+                        mostLoadedWorker.getKey(),
+                        mostLoadedWorker.getValue(),
+                        target,
+                        needed));
+            }
+            return leasesToSteal;
+        } else {
+            if (log.isDebugEnabled()) {
+                log.debug("Worker {} will attempt to steal {} leases from most loaded worker {}. "
+                        + " He has {} leases, target is {}, I need {}, maxLeasesToSteatAtOneTime is {}.",
+                        workerIdentifier,
+                        numLeasesToSteal,
+                        mostLoadedWorker.getKey(),
+                        mostLoadedWorker.getValue(),
+                        target,
+                        needed,
+                        maxLeasesToStealAtOneTime);
+            }
+        }
+
+        String mostLoadedWorkerIdentifier = mostLoadedWorker.getKey();
+        List<T> candidates = new ArrayList<T>();
+        // Collect leases belonging to that worker
+        for (T lease : allLeases.values()) {
+            if (mostLoadedWorkerIdentifier.equals(lease.getLeaseOwner())) {
+                candidates.add(lease);
+            }
+        }
+
+        // Return random ones
+        Collections.shuffle(candidates);
+        int toIndex = Math.min(candidates.size(), numLeasesToSteal);
+        leasesToSteal.addAll(candidates.subList(0, toIndex));
+
+        return leasesToSteal;
+    }
+
+    /**
+     * Count leases by host. Always includes myself, but otherwise only includes hosts that are currently holding
+     * leases.
+     * 
+     * @param expiredLeases list of leases that are currently expired
+     * @return map of workerIdentifier to lease count
+     */
+    private Map<String, Integer> computeLeaseCounts(List<T> expiredLeases) {
+        Map<String, Integer> leaseCounts = new HashMap<String, Integer>();
+
+        // Compute the number of leases per worker by looking through allLeases and ignoring leases that have expired.
+        for (T lease : allLeases.values()) {
+            if (!expiredLeases.contains(lease)) {
+                String leaseOwner = lease.getLeaseOwner();
+                Integer oldCount = leaseCounts.get(leaseOwner);
+                if (oldCount == null) {
+                    leaseCounts.put(leaseOwner, 1);
+                } else {
+                    leaseCounts.put(leaseOwner, oldCount + 1);
+                }
+            }
+        }
+
+        // If I have no leases, I wasn't represented in leaseCounts. Let's fix that.
+        Integer myCount = leaseCounts.get(workerIdentifier);
+        if (myCount == null) {
+            myCount = 0;
+            leaseCounts.put(workerIdentifier, myCount);
+        }
+
+        return leaseCounts;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public String getWorkerIdentifier() {
+        return workerIdentifier;
+    }
+}

amazon-kinesis-client/src/main/java/software/amazon/kinesis/leases/ILeaseRenewer.java

@@ -1,100 +0,0 @@
-/*
- *  Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
- *
- *  Licensed under the Amazon Software License (the "License").
- *  You may not use this file except in compliance with the License.
- *  A copy of the License is located at
- *
- *  http://aws.amazon.com/asl/
- *
- *  or in the "license" file accompanying this file. This file is distributed
- *  on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
- *  express or implied. See the License for the specific language governing
- *  permissions and limitations under the License.
- */
-package software.amazon.kinesis.leases;
-
-import java.util.Collection;
-import java.util.Map;
-import java.util.UUID;
-
-import software.amazon.kinesis.leases.exceptions.DependencyException;
-import software.amazon.kinesis.leases.exceptions.InvalidStateException;
-import software.amazon.kinesis.leases.exceptions.ProvisionedThroughputException;
-import software.amazon.kinesis.leases.Lease;
-
-/**
- * ILeaseRenewer objects are used by LeaseCoordinator to renew leases held by the LeaseCoordinator. Each
- * LeaseCoordinator instance corresponds to one worker, and uses exactly one ILeaseRenewer to manage lease renewal for
- * that worker.
- */
-public interface ILeaseRenewer<T extends Lease> {
-    
-    /**
-     * Bootstrap initial set of leases from the LeaseManager (e.g. upon process restart, pick up leases we own)
-     * @throws DependencyException on unexpected DynamoDB failures
-     * @throws InvalidStateException if lease table doesn't exist
-     * @throws ProvisionedThroughputException if DynamoDB reads fail due to insufficient capacity
-     */
-    public void initialize() throws DependencyException, InvalidStateException, ProvisionedThroughputException;   
-
-    /**
-     * Attempt to renew all currently held leases.
-     * 
-     * @throws DependencyException on unexpected DynamoDB failures
-     * @throws InvalidStateException if lease table does not exist
-     */
-    public void renewLeases() throws DependencyException, InvalidStateException;
-
-    /**
-     * @return currently held leases. Key is shardId, value is corresponding Lease object. A lease is currently held if
-     *         we successfully renewed it on the last run of renewLeases(). Lease objects returned are deep copies -
-     *         their lease counters will not tick.
-     */
-    public Map<String, T> getCurrentlyHeldLeases();
-
-    /**
-     * @param leaseKey key of the lease to retrieve
-     * 
-     * @return a deep copy of a currently held lease, or null if we don't hold the lease
-     */
-    public T getCurrentlyHeldLease(String leaseKey);
-
-    /**
-     * Adds leases to this LeaseRenewer's set of currently held leases. Leases must have lastRenewalNanos set to the
-     * last time the lease counter was incremented before being passed to this method.
-     * 
-     * @param newLeases new leases.
-     */
-    public void addLeasesToRenew(Collection<T> newLeases);
-
-    /**
-     * Clears this LeaseRenewer's set of currently held leases.
-     */
-    public void clearCurrentlyHeldLeases();
-
-    /**
-     * Stops the lease renewer from continunig to maintain the given lease.
-     * 
-     * @param lease the lease to drop.
-     */
-    void dropLease(T lease);
-
-    /**
-     * Update application-specific fields in a currently held lease. Cannot be used to update internal fields such as
-     * leaseCounter, leaseOwner, etc. Fails if we do not hold the lease, or if the concurrency token does not match
-     * the concurrency token on the internal authoritative copy of the lease (ie, if we lost and re-acquired the lease).
-     * 
-     * @param lease lease object containing updated data
-     * @param concurrencyToken obtained by calling Lease.getConcurrencyToken for a currently held lease
-     * 
-     * @return true if update succeeds, false otherwise
-     * 
-     * @throws InvalidStateException if lease table does not exist
-     * @throws ProvisionedThroughputException if DynamoDB update fails due to lack of capacity
-     * @throws DependencyException if DynamoDB update fails in an unexpected way
-     */
-    boolean updateLease(T lease, UUID concurrencyToken)
-        throws DependencyException, InvalidStateException, ProvisionedThroughputException;
-
-}

amazon-kinesis-client/src/main/java/software/amazon/kinesis/leases/ILeaseTaker.java

@@ -1,49 +0,0 @@
-/*
- *  Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
- *
- *  Licensed under the Amazon Software License (the "License").
- *  You may not use this file except in compliance with the License.
- *  A copy of the License is located at
- *
- *  http://aws.amazon.com/asl/
- *
- *  or in the "license" file accompanying this file. This file is distributed
- *  on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
- *  express or implied. See the License for the specific language governing
- *  permissions and limitations under the License.
- */
-package software.amazon.kinesis.leases;
-
-import java.util.Map;
-
-import software.amazon.kinesis.leases.exceptions.DependencyException;
-import software.amazon.kinesis.leases.exceptions.InvalidStateException;
-import software.amazon.kinesis.leases.Lease;
-
-/**
- * ILeaseTaker is used by LeaseCoordinator to take new leases, or leases that other workers fail to renew. Each
- * LeaseCoordinator instance corresponds to one worker and uses exactly one ILeaseTaker to take leases for that worker.
- */
-public interface ILeaseTaker<T extends Lease> {
-
-    /**
-     * Compute the set of leases available to be taken and attempt to take them. Lease taking rules are:
-     * 
-     * 1) If a lease's counter hasn't changed in long enough, try to take it.
-     * 2) If we see a lease we've never seen before, take it only if owner == null. If it's owned, odds are the owner is
-     * holding it. We can't tell until we see it more than once.
-     * 3) For load balancing purposes, you may violate rules 1 and 2 for EXACTLY ONE lease per call of takeLeases().
-     * 
-     * @return map of shardId to Lease object for leases we just successfully took.
-     * 
-     * @throws DependencyException on unexpected DynamoDB failures
-     * @throws InvalidStateException if lease table does not exist
-     */
-    public abstract Map<String, T> takeLeases() throws DependencyException, InvalidStateException;
-
-    /**
-     * @return workerIdentifier for this LeaseTaker
-     */
-    public abstract String getWorkerIdentifier();
-
-}

amazon-kinesis-client/src/main/java/software/amazon/kinesis/leases/KinesisClientLibLeaseCoordinator.java

@@ -18,41 +18,28 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
-import java.util.Objects;
 import java.util.Set;
-import java.util.UUID;
 
-import com.amazonaws.services.kinesis.clientlibrary.exceptions.KinesisClientLibDependencyException;
-import com.amazonaws.services.kinesis.clientlibrary.exceptions.KinesisClientLibException;
-import com.amazonaws.services.kinesis.clientlibrary.exceptions.ShutdownException;
-import com.amazonaws.services.kinesis.clientlibrary.exceptions.ThrottlingException;
-import com.amazonaws.services.kinesis.clientlibrary.exceptions.internal.KinesisClientLibIOException;
+import lombok.Data;
+import lombok.EqualsAndHashCode;
 import lombok.Getter;
+import lombok.NonNull;
+import lombok.RequiredArgsConstructor;
 import lombok.experimental.Accessors;
-import software.amazon.kinesis.processor.ICheckpoint;
-import software.amazon.kinesis.checkpoint.Checkpoint;
-import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
+import lombok.extern.slf4j.Slf4j;
 import software.amazon.kinesis.leases.exceptions.DependencyException;
 import software.amazon.kinesis.leases.exceptions.InvalidStateException;
 import software.amazon.kinesis.leases.exceptions.ProvisionedThroughputException;
 import software.amazon.kinesis.metrics.IMetricsFactory;
 
-import lombok.extern.slf4j.Slf4j;
-
 /**
  * This class is used to coordinate/manage leases owned by this worker process and to get/set checkpoints.
  */
 @Slf4j
-public class KinesisClientLibLeaseCoordinator extends LeaseCoordinator<KinesisClientLease> implements ICheckpoint {
+public class KinesisClientLibLeaseCoordinator extends LeaseCoordinator<KinesisClientLease> {
     private static final long DEFAULT_INITIAL_LEASE_TABLE_READ_CAPACITY = 10L;
     private static final long DEFAULT_INITIAL_LEASE_TABLE_WRITE_CAPACITY = 10L;
 
-    /**
-     * Used to get information about leases for Kinesis shards (e.g. sync shards and leases, check on parent shard
-     * completion).
-     *
-     * @return LeaseManager
-     */
     @Getter
     @Accessors(fluent = true)
     private final ILeaseManager<KinesisClientLease> leaseManager;
@@ -60,53 +47,14 @@ public class KinesisClientLibLeaseCoordinator extends LeaseCoordinator<KinesisCl
     private long initialLeaseTableReadCapacity = DEFAULT_INITIAL_LEASE_TABLE_READ_CAPACITY;
     private long initialLeaseTableWriteCapacity = DEFAULT_INITIAL_LEASE_TABLE_WRITE_CAPACITY;
 
-    /**
-     * @param leaseManager Lease manager which provides CRUD lease operations.
-     * @param workerIdentifier Used to identify this worker process
-     * @param leaseDurationMillis Duration of a lease in milliseconds
-     * @param epsilonMillis Delta for timing operations (e.g. checking lease expiry)
-     */
-    public KinesisClientLibLeaseCoordinator(ILeaseManager<KinesisClientLease> leaseManager,
-            String workerIdentifier,
-            long leaseDurationMillis,
-            long epsilonMillis) {
-        super(leaseManager, workerIdentifier, leaseDurationMillis, epsilonMillis);
-        this.leaseManager = leaseManager;
-    }
-
-    /**
-     * @param leaseManager Lease manager which provides CRUD lease operations.
-     * @param workerIdentifier Used to identify this worker process
-     * @param leaseDurationMillis Duration of a lease in milliseconds
-     * @param epsilonMillis Delta for timing operations (e.g. checking lease expiry)
-     * @param metricsFactory Metrics factory used to emit metrics
-     */
-    public KinesisClientLibLeaseCoordinator(ILeaseManager<KinesisClientLease> leaseManager,
-            String workerIdentifier,
-            long leaseDurationMillis,
-            long epsilonMillis,
-            IMetricsFactory metricsFactory) {
-        super(leaseManager, workerIdentifier, leaseDurationMillis, epsilonMillis, metricsFactory);
-        this.leaseManager = leaseManager;
-    }
-
-    /**
-     * @param leaseManager Lease manager which provides CRUD lease operations.
-     * @param workerIdentifier Used to identify this worker process
-     * @param leaseDurationMillis Duration of a lease in milliseconds
-     * @param epsilonMillis Delta for timing operations (e.g. checking lease expiry)
-     * @param maxLeasesForWorker Max leases this worker can handle at a time
-     * @param maxLeasesToStealAtOneTime Steal up to this many leases at a time (for load balancing)
-     * @param metricsFactory Metrics factory used to emit metrics
-     */
-    public KinesisClientLibLeaseCoordinator(ILeaseManager<KinesisClientLease> leaseManager,
-            String workerIdentifier,
-            long leaseDurationMillis,
-            long epsilonMillis,
-            int maxLeasesForWorker,
-            int maxLeasesToStealAtOneTime,
-            int maxLeaseRenewerThreadCount,
-            IMetricsFactory metricsFactory) {
+    public KinesisClientLibLeaseCoordinator(final ILeaseManager<KinesisClientLease> leaseManager,
+                                            final String workerIdentifier,
+                                            final long leaseDurationMillis,
+                                            final long epsilonMillis,
+                                            final int maxLeasesForWorker,
+                                            final int maxLeasesToStealAtOneTime,
+                                            final int maxLeaseRenewerThreadCount,
+                                            final IMetricsFactory metricsFactory) {
         super(leaseManager, workerIdentifier, leaseDurationMillis, epsilonMillis, maxLeasesForWorker,
                 maxLeasesToStealAtOneTime, maxLeaseRenewerThreadCount, metricsFactory);
         this.leaseManager = leaseManager;
@@ -117,7 +65,7 @@ public class KinesisClientLibLeaseCoordinator extends LeaseCoordinator<KinesisCl
      *        read capacity
      * @return KinesisClientLibLeaseCoordinator
      */
-    public KinesisClientLibLeaseCoordinator withInitialLeaseTableReadCapacity(long readCapacity) {
+    public KinesisClientLibLeaseCoordinator initialLeaseTableReadCapacity(long readCapacity) {
         if (readCapacity <= 0) {
             throw new IllegalArgumentException("readCapacity should be >= 1");
         }
@@ -130,7 +78,7 @@ public class KinesisClientLibLeaseCoordinator extends LeaseCoordinator<KinesisCl
      *        write capacity
      * @return KinesisClientLibLeaseCoordinator
      */
-    public KinesisClientLibLeaseCoordinator withInitialLeaseTableWriteCapacity(long writeCapacity) {
+    public KinesisClientLibLeaseCoordinator initialLeaseTableWriteCapacity(long writeCapacity) {
         if (writeCapacity <= 0) {
             throw new IllegalArgumentException("writeCapacity should be >= 1");
         }
@@ -138,138 +86,6 @@ public class KinesisClientLibLeaseCoordinator extends LeaseCoordinator<KinesisCl
         return this;
     }
 
-    /**
-     * Sets the checkpoint for a shard and updates ownerSwitchesSinceCheckpoint.
-     * 
-     * @param shardId shardId to update the checkpoint for
-     * @param checkpoint checkpoint value to set
-     * @param concurrencyToken obtained by calling Lease.concurrencyToken for a currently held lease
-     * 
-     * @return true if checkpoint update succeeded, false otherwise
-     * 
-     * @throws InvalidStateException if lease table does not exist
-     * @throws ProvisionedThroughputException if DynamoDB update fails due to lack of capacity
-     * @throws DependencyException if DynamoDB update fails in an unexpected way
-     */
-    public boolean setCheckpoint(String shardId, ExtendedSequenceNumber checkpoint, UUID concurrencyToken)
-        throws DependencyException, InvalidStateException, ProvisionedThroughputException {
-        KinesisClientLease lease = getCurrentlyHeldLease(shardId);
-        if (lease == null) {
-            log.info("Worker {} could not update checkpoint for shard {} because it does not hold the lease",
-                    getWorkerIdentifier(), shardId);
-            return false;
-        }
-
-        lease.setCheckpoint(checkpoint);
-        lease.setPendingCheckpoint(null);
-        lease.setOwnerSwitchesSinceCheckpoint(0L);
-
-        return updateLease(lease, concurrencyToken);
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    @Override
-    public void setCheckpoint(String shardId, ExtendedSequenceNumber checkpointValue, String concurrencyToken)
-        throws KinesisClientLibException {
-        try {
-            boolean wasSuccessful = setCheckpoint(shardId, checkpointValue, UUID.fromString(concurrencyToken));
-            if (!wasSuccessful) {
-                throw new ShutdownException("Can't update checkpoint - instance doesn't hold the lease for this shard");
-            }
-        } catch (ProvisionedThroughputException e) {
-            throw new ThrottlingException("Got throttled while updating checkpoint.", e);
-        } catch (InvalidStateException e) {
-            String message = "Unable to save checkpoint for shardId " + shardId;
-            log.error(message, e);
-            throw new com.amazonaws.services.kinesis.clientlibrary.exceptions.InvalidStateException(message, e);
-        } catch (DependencyException e) {
-            throw new KinesisClientLibDependencyException("Unable to save checkpoint for shardId " + shardId, e);
-        }
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    @Override
-    public ExtendedSequenceNumber getCheckpoint(String shardId) throws KinesisClientLibException {
-        try {
-            return leaseManager.getLease(shardId).getCheckpoint();
-        } catch (DependencyException | InvalidStateException | ProvisionedThroughputException e) {
-            String message = "Unable to fetch checkpoint for shardId " + shardId;
-            log.error(message, e);
-            throw new KinesisClientLibIOException(message, e);
-        }
-    }
-
-    /**
-     * Records pending checkpoint for a shard. Does not modify checkpoint or ownerSwitchesSinceCheckpoint.
-     *
-     * @param shardId shardId to update the checkpoint for
-     * @param pendingCheckpoint pending checkpoint value to set, not null
-     * @param concurrencyToken obtained by calling Lease.concurrencyToken for a currently held lease
-     *
-     * @return true if setting the pending checkpoint succeeded, false otherwise
-     *
-     * @throws InvalidStateException if lease table does not exist
-     * @throws ProvisionedThroughputException if DynamoDB update fails due to lack of capacity
-     * @throws DependencyException if DynamoDB update fails in an unexpected way
-     */
-    boolean prepareCheckpoint(String shardId, ExtendedSequenceNumber pendingCheckpoint, UUID concurrencyToken)
-            throws DependencyException, InvalidStateException, ProvisionedThroughputException {
-        KinesisClientLease lease = getCurrentlyHeldLease(shardId);
-        if (lease == null) {
-            log.info("Worker {} could not prepare checkpoint for shard {} because it does not hold the lease",
-                    getWorkerIdentifier(), shardId);
-            return false;
-        }
-
-        lease.setPendingCheckpoint(Objects.requireNonNull(pendingCheckpoint, "pendingCheckpoint should not be null"));
-        return updateLease(lease, concurrencyToken);
-    }
-
-
-    /**
-     * {@inheritDoc}
-     */
-    @Override
-    public void prepareCheckpoint(String shardId,
-                                  ExtendedSequenceNumber pendingCheckpointValue,
-                                  String concurrencyToken) throws KinesisClientLibException {
-        try {
-            boolean wasSuccessful =
-                    prepareCheckpoint(shardId, pendingCheckpointValue, UUID.fromString(concurrencyToken));
-            if (!wasSuccessful) {
-                throw new ShutdownException(
-                        "Can't prepare checkpoint - instance doesn't hold the lease for this shard");
-            }
-        } catch (ProvisionedThroughputException e) {
-            throw new ThrottlingException("Got throttled while preparing checkpoint.", e);
-        } catch (InvalidStateException e) {
-            String message = "Unable to prepare checkpoint for shardId " + shardId;
-            log.error(message, e);
-            throw new com.amazonaws.services.kinesis.clientlibrary.exceptions.InvalidStateException(message, e);
-        } catch (DependencyException e) {
-            throw new KinesisClientLibDependencyException("Unable to prepare checkpoint for shardId " + shardId, e);
-        }
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    @Override
-    public Checkpoint getCheckpointObject(String shardId) throws KinesisClientLibException {
-        try {
-            KinesisClientLease lease = leaseManager.getLease(shardId);
-            return new Checkpoint(lease.getCheckpoint(), lease.getPendingCheckpoint());
-        } catch (DependencyException | InvalidStateException | ProvisionedThroughputException e) {
-            String message = "Unable to fetch checkpoint for shardId " + shardId;
-            log.error(message, e);
-            throw new KinesisClientLibIOException(message, e);
-        }
-    }
-
     /**
      * @return Current shard/lease assignments
      */

amazon-kinesis-client/src/main/java/software/amazon/kinesis/leases/LeaseCoordinator.java

@@ -66,7 +66,7 @@ public class LeaseCoordinator<T extends Lease> {
             .setNameFormat("LeaseRenewer-%04d").setDaemon(true).build();
 
     private final ILeaseRenewer<T> leaseRenewer;
-    private final ILeaseTaker<T> leaseTaker;
+    private final LeaseTaker<T> leaseTaker;
     private final long renewerIntervalMillis;
     private final long takerIntervalMillis;
 
@@ -133,7 +133,7 @@ public class LeaseCoordinator<T extends Lease> {
             int maxLeaseRenewerThreadCount,
             IMetricsFactory metricsFactory) {
         this.leaseRenewalThreadpool = getLeaseRenewalExecutorService(maxLeaseRenewerThreadCount);
-        this.leaseTaker = new LeaseTaker<T>(leaseManager, workerIdentifier, leaseDurationMillis)
+        this.leaseTaker = new DynamoDBLeaseTaker<T>(leaseManager, workerIdentifier, leaseDurationMillis)
                 .withMaxLeasesForWorker(maxLeasesForWorker)
                 .withMaxLeasesToStealAtOneTime(maxLeasesToStealAtOneTime);
         this.leaseRenewer = new LeaseRenewer<T>(

amazon-kinesis-client/src/main/java/software/amazon/kinesis/leases/LeaseRenewer.java

@@ -14,397 +14,87 @@
  */
 package software.amazon.kinesis.leases;
 
-import java.util.ArrayList;
 import java.util.Collection;
-import java.util.HashMap;
-import java.util.LinkedList;
-import java.util.List;
 import java.util.Map;
 import java.util.UUID;
-import java.util.concurrent.Callable;
-import java.util.concurrent.ConcurrentNavigableMap;
-import java.util.concurrent.ConcurrentSkipListMap;
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Future;
-import java.util.concurrent.TimeUnit;
 
-import com.amazonaws.services.cloudwatch.model.StandardUnit;
 import software.amazon.kinesis.leases.exceptions.DependencyException;
 import software.amazon.kinesis.leases.exceptions.InvalidStateException;
 import software.amazon.kinesis.leases.exceptions.ProvisionedThroughputException;
-import software.amazon.kinesis.metrics.MetricsHelper;
-import software.amazon.kinesis.metrics.ThreadSafeMetricsDelegatingScope;
-import software.amazon.kinesis.metrics.IMetricsScope;
-import software.amazon.kinesis.metrics.MetricsLevel;
-
-import lombok.extern.slf4j.Slf4j;
+import software.amazon.kinesis.leases.Lease;
 
 /**
- * An implementation of ILeaseRenewer that uses DynamoDB via LeaseManager.
+ * ILeaseRenewer objects are used by LeaseCoordinator to renew leases held by the LeaseCoordinator. Each
+ * LeaseCoordinator instance corresponds to one worker, and uses exactly one ILeaseRenewer to manage lease renewal for
+ * that worker.
  */
-@Slf4j
-public class LeaseRenewer<T extends Lease> implements ILeaseRenewer<T> {
-    private static final int RENEWAL_RETRIES = 2;
-
-    private final ILeaseManager<T> leaseManager;
-    private final ConcurrentNavigableMap<String, T> ownedLeases = new ConcurrentSkipListMap<String, T>();
-    private final String workerIdentifier;
-    private final long leaseDurationNanos;
-    private final ExecutorService executorService;
+public interface ILeaseRenewer<T extends Lease> {
+    
+    /**
+     * Bootstrap initial set of leases from the LeaseManager (e.g. upon process restart, pick up leases we own)
+     * @throws DependencyException on unexpected DynamoDB failures
+     * @throws InvalidStateException if lease table doesn't exist
+     * @throws ProvisionedThroughputException if DynamoDB reads fail due to insufficient capacity
+     */
+    public void initialize() throws DependencyException, InvalidStateException, ProvisionedThroughputException;   
 
     /**
-     * Constructor.
+     * Attempt to renew all currently held leases.
      * 
-     * @param leaseManager LeaseManager to use
-     * @param workerIdentifier identifier of this worker
-     * @param leaseDurationMillis duration of a lease in milliseconds
-     * @param executorService ExecutorService to use for renewing leases in parallel
+     * @throws DependencyException on unexpected DynamoDB failures
+     * @throws InvalidStateException if lease table does not exist
      */
-    public LeaseRenewer(ILeaseManager<T> leaseManager, String workerIdentifier, long leaseDurationMillis,
-            ExecutorService executorService) {
-        this.leaseManager = leaseManager;
-        this.workerIdentifier = workerIdentifier;
-        this.leaseDurationNanos = TimeUnit.MILLISECONDS.toNanos(leaseDurationMillis);
-        this.executorService = executorService;
-    }
+    public void renewLeases() throws DependencyException, InvalidStateException;
 
     /**
-     * {@inheritDoc}
+     * @return currently held leases. Key is shardId, value is corresponding Lease object. A lease is currently held if
+     *         we successfully renewed it on the last run of renewLeases(). Lease objects returned are deep copies -
+     *         their lease counters will not tick.
      */
-    @Override
-    public void renewLeases() throws DependencyException, InvalidStateException {
-        if (log.isDebugEnabled()) {
-            // Due to the eventually consistent nature of ConcurrentNavigableMap iterators, this log entry may become
-            // inaccurate during iteration.
-            log.debug("Worker {} holding %d leases: {}",
-                    workerIdentifier,
-                    ownedLeases.size(),
-                    ownedLeases);
-        }
-
-        /*
-         * Lease renewals are done in parallel so many leases can be renewed for short lease fail over time
-         * configuration. In this case, metrics scope is also shared across different threads, so scope must be thread
-         * safe.
-         */
-        IMetricsScope renewLeaseTaskMetricsScope = new ThreadSafeMetricsDelegatingScope(
-                MetricsHelper.getMetricsScope());
-
-        /*
-         * We iterate in descending order here so that the synchronized(lease) inside renewLease doesn't "lead" calls
-         * to getCurrentlyHeldLeases. They'll still cross paths, but they won't interleave their executions.
-         */
-        int lostLeases = 0;
-        List<Future<Boolean>> renewLeaseTasks = new ArrayList<Future<Boolean>>();
-        for (T lease : ownedLeases.descendingMap().values()) {
-            renewLeaseTasks.add(executorService.submit(new RenewLeaseTask(lease, renewLeaseTaskMetricsScope)));
-        }
-        int leasesInUnknownState = 0;
-        Exception lastException = null;
-        for (Future<Boolean> renewLeaseTask : renewLeaseTasks) {
-            try {
-                if (!renewLeaseTask.get()) {
-                    lostLeases++;
-                }
-            } catch (InterruptedException e) {
-                log.info("Interrupted while waiting for a lease to renew.");
-                leasesInUnknownState += 1;
-                Thread.currentThread().interrupt();
-            } catch (ExecutionException e) {
-                log.error("Encountered an exception while renewing a lease.", e.getCause());
-                leasesInUnknownState += 1;
-                lastException = e;
-            }
-        }
-
-        renewLeaseTaskMetricsScope.addData(
-                "LostLeases", lostLeases, StandardUnit.Count, MetricsLevel.SUMMARY);
-        renewLeaseTaskMetricsScope.addData(
-                "CurrentLeases", ownedLeases.size(), StandardUnit.Count, MetricsLevel.SUMMARY);
-        if (leasesInUnknownState > 0) {
-            throw new DependencyException(String.format("Encountered an exception while renewing leases. "
-                    + "The number of leases which might not have been renewed is %d",
-                    leasesInUnknownState),
-                    lastException);
-        }
-    }
-
-    private class RenewLeaseTask implements Callable<Boolean> {
-
-        private final T lease;
-        private final IMetricsScope metricsScope;
-
-        public RenewLeaseTask(T lease, IMetricsScope metricsScope) {
-            this.lease = lease;
-            this.metricsScope = metricsScope;
-        }
-
-        @Override
-        public Boolean call() throws Exception {
-            MetricsHelper.setMetricsScope(metricsScope);
-            try {
-                return renewLease(lease);
-            } finally {
-                MetricsHelper.unsetMetricsScope();
-            }
-        }
-    }
-
-    private boolean renewLease(T lease) throws DependencyException, InvalidStateException {
-        return renewLease(lease, false);
-    }
-
-    private boolean renewLease(T lease, boolean renewEvenIfExpired) throws DependencyException, InvalidStateException {
-        String leaseKey = lease.getLeaseKey();
-
-        boolean success = false;
-        boolean renewedLease = false;
-        long startTime = System.currentTimeMillis();
-        try {
-            for (int i = 1; i <= RENEWAL_RETRIES; i++) {
-                try {
-                    synchronized (lease) {
-                        // Don't renew expired lease during regular renewals. getCopyOfHeldLease may have returned null
-                        // triggering the application processing to treat this as a lost lease (fail checkpoint with
-                        // ShutdownException).
-                        boolean isLeaseExpired = lease.isExpired(leaseDurationNanos, System.nanoTime());
-                        if (renewEvenIfExpired || !isLeaseExpired) {
-                            renewedLease = leaseManager.renewLease(lease);
-                        }
-                        if (renewedLease) {
-                            lease.setLastCounterIncrementNanos(System.nanoTime());
-                        }
-                    }
-
-                    if (renewedLease) {
-                        if (log.isDebugEnabled()) {
-                            log.debug("Worker {} successfully renewed lease with key {}",
-                                    workerIdentifier,
-                                    leaseKey);
-                        }
-                    } else {
-                        log.info("Worker {} lost lease with key {}", workerIdentifier, leaseKey);
-                        ownedLeases.remove(leaseKey);
-                    }
-
-                    success = true;
-                    break;
-                } catch (ProvisionedThroughputException e) {
-                    log.info("Worker {} could not renew lease with key {} on try {} out of {} due to capacity",
-                            workerIdentifier,
-                            leaseKey,
-                            i,
-                            RENEWAL_RETRIES);
-                }
-            }
-        } finally {
-            MetricsHelper.addSuccessAndLatency("RenewLease", startTime, success, MetricsLevel.DETAILED);
-        }
-
-        return renewedLease;
-    }
+    public Map<String, T> getCurrentlyHeldLeases();
 
     /**
-     * {@inheritDoc}
-     */
-    @Override
-    public Map<String, T> getCurrentlyHeldLeases() {
-        Map<String, T> result = new HashMap<String, T>();
-        long now = System.nanoTime();
-
-        for (String leaseKey : ownedLeases.keySet()) {
-            T copy = getCopyOfHeldLease(leaseKey, now);
-            if (copy != null) {
-                result.put(copy.getLeaseKey(), copy);
-            }
-        }
-
-        return result;
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    @Override
-    public T getCurrentlyHeldLease(String leaseKey) {
-        return getCopyOfHeldLease(leaseKey, System.nanoTime());
-    }
-
-    /**
-     * Internal method to return a lease with a specific lease key only if we currently hold it.
+     * @param leaseKey key of the lease to retrieve
      * 
-     * @param leaseKey key of lease to return
-     * @param now current timestamp for old-ness checking
-     * @return non-authoritative copy of the held lease, or null if we don't currently hold it
+     * @return a deep copy of a currently held lease, or null if we don't hold the lease
      */
-    private T getCopyOfHeldLease(String leaseKey, long now) {
-        T authoritativeLease = ownedLeases.get(leaseKey);
-        if (authoritativeLease == null) {
-            return null;
-        } else {
-            T copy = null;
-            synchronized (authoritativeLease) {
-                copy = authoritativeLease.copy();
-            }
-
-            if (copy.isExpired(leaseDurationNanos, now)) {
-                log.info("getCurrentlyHeldLease not returning lease with key {} because it is expired",
-                        copy.getLeaseKey());
-                return null;
-            } else {
-                return copy;
-            }
-        }
-    }
+    public T getCurrentlyHeldLease(String leaseKey);
 
     /**
-     * {@inheritDoc}
+     * Adds leases to this LeaseRenewer's set of currently held leases. Leases must have lastRenewalNanos set to the
+     * last time the lease counter was incremented before being passed to this method.
+     * 
+     * @param newLeases new leases.
      */
-    @Override
-    public boolean updateLease(T lease, UUID concurrencyToken)
-        throws DependencyException, InvalidStateException, ProvisionedThroughputException {
-        verifyNotNull(lease, "lease cannot be null");
-        verifyNotNull(lease.getLeaseKey(), "leaseKey cannot be null");
-        verifyNotNull(concurrencyToken, "concurrencyToken cannot be null");
-
-        String leaseKey = lease.getLeaseKey();
-        T authoritativeLease = ownedLeases.get(leaseKey);
-
-        if (authoritativeLease == null) {
-            log.info("Worker {} could not update lease with key {} because it does not hold it",
-                    workerIdentifier,
-                    leaseKey);
-            return false;
-        }
-
-        /*
-         * If the passed-in concurrency token doesn't match the concurrency token of the authoritative lease, it means
-         * the lease was lost and regained between when the caller acquired his concurrency token and when the caller
-         * called update.
-         */
-        if (!authoritativeLease.getConcurrencyToken().equals(concurrencyToken)) {
-            log.info("Worker {} refusing to update lease with key {} because"
-                    + " concurrency tokens don't match", workerIdentifier, leaseKey);
-            return false;
-        }
-
-        long startTime = System.currentTimeMillis();
-        boolean success = false;
-        try {
-            synchronized (authoritativeLease) {
-                authoritativeLease.update(lease);
-                boolean updatedLease = leaseManager.updateLease(authoritativeLease);
-                if (updatedLease) {
-                    // Updates increment the counter
-                    authoritativeLease.setLastCounterIncrementNanos(System.nanoTime());
-                } else {
-                    /*
-                     * If updateLease returns false, it means someone took the lease from us. Remove the lease
-                     * from our set of owned leases pro-actively rather than waiting for a run of renewLeases().
-                     */
-                    log.info("Worker {} lost lease with key {} - discovered during update",
-                            workerIdentifier,
-                            leaseKey);
-
-                    /*
-                     * Remove only if the value currently in the map is the same as the authoritative lease. We're
-                     * guarding against a pause after the concurrency token check above. It plays out like so:
-                     * 
-                     * 1) Concurrency token check passes
-                     * 2) Pause. Lose lease, re-acquire lease. This requires at least one lease counter update.
-                     * 3) Unpause. leaseManager.updateLease fails conditional write due to counter updates, returns
-                     * false.
-                     * 4) ownedLeases.remove(key, value) doesn't do anything because authoritativeLease does not
-                     * .equals() the re-acquired version in the map on the basis of lease counter. This is what we want.
-                     * If we just used ownedLease.remove(key), we would have pro-actively removed a lease incorrectly.
-                     * 
-                     * Note that there is a subtlety here - Lease.equals() deliberately does not check the concurrency
-                     * token, but it does check the lease counter, so this scheme works.
-                     */
-                    ownedLeases.remove(leaseKey, authoritativeLease);
-                }
-
-                success = true;
-                return updatedLease;
-            }
-        } finally {
-            MetricsHelper.addSuccessAndLatency("UpdateLease", startTime, success, MetricsLevel.DETAILED);
-        }
-    }
+    public void addLeasesToRenew(Collection<T> newLeases);
 
     /**
-     * {@inheritDoc}
+     * Clears this LeaseRenewer's set of currently held leases.
      */
-    @Override
-    public void addLeasesToRenew(Collection<T> newLeases) {
-        verifyNotNull(newLeases, "newLeases cannot be null");
-
-        for (T lease : newLeases) {
-            if (lease.getLastCounterIncrementNanos() == null) {
-                log.info("addLeasesToRenew ignoring lease with key {} because it does not have lastRenewalNanos set",
-                        lease.getLeaseKey());
-                continue;
-            }
-
-            T authoritativeLease = lease.copy();
-
-            /*
-             * Assign a concurrency token when we add this to the set of currently owned leases. This ensures that
-             * every time we acquire a lease, it gets a new concurrency token.
-             */
-            authoritativeLease.setConcurrencyToken(UUID.randomUUID());
-            ownedLeases.put(authoritativeLease.getLeaseKey(), authoritativeLease);
-        }
-    }
+    public void clearCurrentlyHeldLeases();
 
     /**
-     * {@inheritDoc}
-     */
-    @Override
-    public void clearCurrentlyHeldLeases() {
-        ownedLeases.clear();
-    }
-
-    /**
-     * {@inheritDoc}
+     * Stops the lease renewer from continunig to maintain the given lease.
+     * 
      * @param lease the lease to drop.
      */
-    @Override
-    public void dropLease(T lease) {
-        ownedLeases.remove(lease.getLeaseKey());
-    }
+    void dropLease(T lease);
 
     /**
-     * {@inheritDoc}
+     * Update application-specific fields in a currently held lease. Cannot be used to update internal fields such as
+     * leaseCounter, leaseOwner, etc. Fails if we do not hold the lease, or if the concurrency token does not match
+     * the concurrency token on the internal authoritative copy of the lease (ie, if we lost and re-acquired the lease).
+     * 
+     * @param lease lease object containing updated data
+     * @param concurrencyToken obtained by calling Lease.getConcurrencyToken for a currently held lease
+     * 
+     * @return true if update succeeds, false otherwise
+     * 
+     * @throws InvalidStateException if lease table does not exist
+     * @throws ProvisionedThroughputException if DynamoDB update fails due to lack of capacity
+     * @throws DependencyException if DynamoDB update fails in an unexpected way
      */
-    @Override
-    public void initialize() throws DependencyException, InvalidStateException, ProvisionedThroughputException {
-        Collection<T> leases = leaseManager.listLeases();
-        List<T> myLeases = new LinkedList<T>();
-        boolean renewEvenIfExpired = true;
-
-        for (T lease : leases) {
-            if (workerIdentifier.equals(lease.getLeaseOwner())) {
-                log.info(" Worker {} found lease {}", workerIdentifier, lease);
-                // Okay to renew even if lease is expired, because we start with an empty list and we add the lease to
-                // our list only after a successful renew. So we don't need to worry about the edge case where we could
-                // continue renewing a lease after signaling a lease loss to the application.
-                if (renewLease(lease, renewEvenIfExpired)) {
-                    myLeases.add(lease);
-                }
-            } else {
-                log.debug("Worker {} ignoring lease {} ", workerIdentifier, lease);
-            }
-        }
-
-        addLeasesToRenew(myLeases);
-    }
-
-    private void verifyNotNull(Object object, String message) {
-        if (object == null) {
-            throw new IllegalArgumentException(message);
-        }
-    }
+    boolean updateLease(T lease, UUID concurrencyToken)
+        throws DependencyException, InvalidStateException, ProvisionedThroughputException;
 
 }

amazon-kinesis-client/src/main/java/software/amazon/kinesis/leases/LeaseTaker.java

@@ -14,522 +14,36 @@
  */
 package software.amazon.kinesis.leases;
 
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.List;
 import java.util.Map;
-import java.util.Map.Entry;
-import java.util.Set;
-import java.util.concurrent.Callable;
-import java.util.concurrent.TimeUnit;
 
-import com.amazonaws.services.cloudwatch.model.StandardUnit;
 import software.amazon.kinesis.leases.exceptions.DependencyException;
 import software.amazon.kinesis.leases.exceptions.InvalidStateException;
-import software.amazon.kinesis.leases.exceptions.ProvisionedThroughputException;
-import software.amazon.kinesis.metrics.MetricsHelper;
-import software.amazon.kinesis.metrics.IMetricsScope;
-import software.amazon.kinesis.metrics.MetricsLevel;
-
-import lombok.extern.slf4j.Slf4j;
+import software.amazon.kinesis.leases.Lease;
 
 /**
- * An implementation of ILeaseTaker that uses DynamoDB via LeaseManager.
+ * ILeaseTaker is used by LeaseCoordinator to take new leases, or leases that other workers fail to renew. Each
+ * LeaseCoordinator instance corresponds to one worker and uses exactly one ILeaseTaker to take leases for that worker.
  */
-@Slf4j
-public class LeaseTaker<T extends Lease> implements ILeaseTaker<T> {
-    private static final int TAKE_RETRIES = 3;
-    private static final int SCAN_RETRIES = 1;
-
-    // See note on takeLeases(Callable) for why we have this callable.
-    private static final Callable<Long> SYSTEM_CLOCK_CALLABLE = new Callable<Long>() {
-
-        @Override
-        public Long call() {
-            return System.nanoTime();
-        }
-    };
-
-    private final ILeaseManager<T> leaseManager;
-    private final String workerIdentifier;
-    private final Map<String, T> allLeases = new HashMap<String, T>();
-    private final long leaseDurationNanos;
-    private int maxLeasesForWorker = Integer.MAX_VALUE;
-    private int maxLeasesToStealAtOneTime = 1;
-
-    private long lastScanTimeNanos = 0L;
-
-    public LeaseTaker(ILeaseManager<T> leaseManager, String workerIdentifier, long leaseDurationMillis) {
-        this.leaseManager = leaseManager;
-        this.workerIdentifier = workerIdentifier;
-        this.leaseDurationNanos = TimeUnit.MILLISECONDS.toNanos(leaseDurationMillis);
-    }
+public interface LeaseTaker<T extends Lease> {
 
     /**
-     * Worker will not acquire more than the specified max number of leases even if there are more
-     * shards that need to be processed. This can be used in scenarios where a worker is resource constrained or
-     * to prevent lease thrashing when small number of workers pick up all leases for small amount of time during
-     * deployment.
-     * Note that setting a low value may cause data loss (e.g. if there aren't enough Workers to make progress on all
-     * shards). When setting the value for this property, one must ensure enough workers are present to process
-     * shards and should consider future resharding, child shards that may be blocked on parent shards, some workers
-     * becoming unhealthy, etc.
-     *
-     * @param maxLeasesForWorker Max leases this Worker can handle at a time
-     * @return LeaseTaker
+     * Compute the set of leases available to be taken and attempt to take them. Lease taking rules are:
+     * 
+     * 1) If a lease's counter hasn't changed in long enough, try to take it.
+     * 2) If we see a lease we've never seen before, take it only if owner == null. If it's owned, odds are the owner is
+     * holding it. We can't tell until we see it more than once.
+     * 3) For load balancing purposes, you may violate rules 1 and 2 for EXACTLY ONE lease per call of takeLeases().
+     * 
+     * @return map of shardId to Lease object for leases we just successfully took.
+     * 
+     * @throws DependencyException on unexpected DynamoDB failures
+     * @throws InvalidStateException if lease table does not exist
      */
-    public LeaseTaker<T> withMaxLeasesForWorker(int maxLeasesForWorker) {
-        if (maxLeasesForWorker <= 0) {
-            throw new IllegalArgumentException("maxLeasesForWorker should be >= 1");
-        }
-        this.maxLeasesForWorker = maxLeasesForWorker;
-        return this;
-    }
+    public abstract Map<String, T> takeLeases() throws DependencyException, InvalidStateException;
 
     /**
-     * Max leases to steal from a more loaded Worker at one time (for load balancing).
-     * Setting this to a higher number can allow for faster load convergence (e.g. during deployments, cold starts),
-     * but can cause higher churn in the system.
-     *
-     * @param maxLeasesToStealAtOneTime Steal up to this many leases at one time (for load balancing)
-     * @return LeaseTaker
+     * @return workerIdentifier for this LeaseTaker
      */
-    public LeaseTaker<T> withMaxLeasesToStealAtOneTime(int maxLeasesToStealAtOneTime) {
-        if (maxLeasesToStealAtOneTime <= 0) {
-            throw new IllegalArgumentException("maxLeasesToStealAtOneTime should be >= 1");
-        }
-        this.maxLeasesToStealAtOneTime = maxLeasesToStealAtOneTime;
-        return this;
-    }
+    public abstract String getWorkerIdentifier();
 
-    /**
-     * {@inheritDoc}
-     */
-    @Override
-    public Map<String, T> takeLeases() throws DependencyException, InvalidStateException {
-        return takeLeases(SYSTEM_CLOCK_CALLABLE);
-    }
-
-    /**
-     * Internal implementation of takeLeases. Takes a callable that can provide the time to enable test cases without
-     * Thread.sleep. Takes a callable instead of a raw time value because the time needs to be computed as-of
-     * immediately after the scan.
-     * 
-     * @param timeProvider Callable that will supply the time
-     * 
-     * @return map of lease key to taken lease
-     * 
-     * @throws DependencyException
-     * @throws InvalidStateException
-     */
-    synchronized Map<String, T> takeLeases(Callable<Long> timeProvider)
-        throws DependencyException, InvalidStateException {
-        // Key is leaseKey
-        Map<String, T> takenLeases = new HashMap<String, T>();
-
-        long startTime = System.currentTimeMillis();
-        boolean success = false;
-
-        ProvisionedThroughputException lastException = null;
-
-        try {
-            for (int i = 1; i <= SCAN_RETRIES; i++) {
-                try {
-                    updateAllLeases(timeProvider);
-                    success = true;
-                } catch (ProvisionedThroughputException e) {
-                    log.info("Worker {} could not find expired leases on try {} out of {}",
-                            workerIdentifier,
-                            i,
-                            TAKE_RETRIES);
-                    lastException = e;
-                }
-            }
-        } finally {
-            MetricsHelper.addSuccessAndLatency("ListLeases", startTime, success, MetricsLevel.DETAILED);
-        }
-
-        if (lastException != null) {
-            log.error("Worker {} could not scan leases table, aborting takeLeases. Exception caught by last retry:",
-                    workerIdentifier,
-                    lastException);
-            return takenLeases;
-        }
-
-        List<T> expiredLeases = getExpiredLeases();
-
-        Set<T> leasesToTake = computeLeasesToTake(expiredLeases);
-        Set<String> untakenLeaseKeys = new HashSet<String>();
-
-        for (T lease : leasesToTake) {
-            String leaseKey = lease.getLeaseKey();
-
-            startTime = System.currentTimeMillis();
-            success = false;
-            try {
-                for (int i = 1; i <= TAKE_RETRIES; i++) {
-                    try {
-                        if (leaseManager.takeLease(lease, workerIdentifier)) {
-                            lease.setLastCounterIncrementNanos(System.nanoTime());
-                            takenLeases.put(leaseKey, lease);
-                        } else {
-                            untakenLeaseKeys.add(leaseKey);
-                        }
-
-                        success = true;
-                        break;
-                    } catch (ProvisionedThroughputException e) {
-                        log.info("Could not take lease with key {} for worker {} on try {} out of {} due to capacity",
-                                leaseKey,
-                                workerIdentifier,
-                                i,
-                                TAKE_RETRIES);
-                    }
-                }
-            } finally {
-                MetricsHelper.addSuccessAndLatency("TakeLease", startTime, success, MetricsLevel.DETAILED);
-            }
-        }
-
-        if (takenLeases.size() > 0) {
-            log.info("Worker {} successfully took {} leases: {}",
-                    workerIdentifier,
-                    takenLeases.size(),
-                    stringJoin(takenLeases.keySet(), ", "));
-        }
-
-        if (untakenLeaseKeys.size() > 0) {
-            log.info("Worker {} failed to take {} leases: {}",
-                    workerIdentifier,
-                    untakenLeaseKeys.size(),
-                    stringJoin(untakenLeaseKeys, ", "));
-        }
-
-        MetricsHelper.getMetricsScope().addData(
-                "TakenLeases", takenLeases.size(), StandardUnit.Count, MetricsLevel.SUMMARY);
-
-        return takenLeases;
-    }
-
-    /** Package access for testing purposes.
-     *
-     * @param strings
-     * @param delimiter
-     * @return Joined string.
-     */
-    static String stringJoin(Collection<String> strings, String delimiter) {
-        StringBuilder builder = new StringBuilder();
-        boolean needDelimiter = false;
-        for (String string : strings) {
-            if (needDelimiter) {
-                builder.append(delimiter);
-            }
-            builder.append(string);
-            needDelimiter = true;
-        }
-        
-        return builder.toString();
-    }
-
-    /**
-     * Scan all leases and update lastRenewalTime. Add new leases and delete old leases.
-     * 
-     * @param timeProvider callable that supplies the current time
-     * 
-     * @return list of expired leases, possibly empty, never null.
-     * 
-     * @throws ProvisionedThroughputException if listLeases fails due to lack of provisioned throughput
-     * @throws InvalidStateException if the lease table does not exist
-     * @throws DependencyException if listLeases fails in an unexpected way
-     */
-    private void updateAllLeases(Callable<Long> timeProvider)
-        throws DependencyException, InvalidStateException, ProvisionedThroughputException {
-        List<T> freshList = leaseManager.listLeases();
-        try {
-            lastScanTimeNanos = timeProvider.call();
-        } catch (Exception e) {
-            throw new DependencyException("Exception caught from timeProvider", e);
-        }
-
-        // This set will hold the lease keys not updated by the previous listLeases call.
-        Set<String> notUpdated = new HashSet<String>(allLeases.keySet());
-
-        // Iterate over all leases, finding ones to try to acquire that haven't changed since the last iteration
-        for (T lease : freshList) {
-            String leaseKey = lease.getLeaseKey();
-
-            T oldLease = allLeases.get(leaseKey);
-            allLeases.put(leaseKey, lease);
-            notUpdated.remove(leaseKey);
-
-            if (oldLease != null) {
-                // If we've seen this lease before...
-                if (oldLease.getLeaseCounter().equals(lease.getLeaseCounter())) {
-                    // ...and the counter hasn't changed, propagate the lastRenewalNanos time from the old lease
-                    lease.setLastCounterIncrementNanos(oldLease.getLastCounterIncrementNanos());
-                } else {
-                    // ...and the counter has changed, set lastRenewalNanos to the time of the scan.
-                    lease.setLastCounterIncrementNanos(lastScanTimeNanos);
-                }
-            } else {
-                if (lease.getLeaseOwner() == null) {
-                    // if this new lease is unowned, it's never been renewed.
-                    lease.setLastCounterIncrementNanos(0L);
-
-                    if (log.isDebugEnabled()) {
-                        log.debug("Treating new lease with key {} as never renewed because it is new and unowned.",
-                                leaseKey);
-                    }
-                } else {
-                    // if this new lease is owned, treat it as renewed as of the scan
-                    lease.setLastCounterIncrementNanos(lastScanTimeNanos);
-                    if (log.isDebugEnabled()) {
-                        log.debug("Treating new lease with key {} as recently renewed because it is new and owned.",
-                                leaseKey);
-                    }
-                }
-            }
-        }
-
-        // Remove dead leases from allLeases
-        for (String key : notUpdated) {
-            allLeases.remove(key);
-        }
-    }
-
-    /**
-     * @return list of leases that were expired as of our last scan.
-     */
-    private List<T> getExpiredLeases() {
-        List<T> expiredLeases = new ArrayList<T>();
-
-        for (T lease : allLeases.values()) {
-            if (lease.isExpired(leaseDurationNanos, lastScanTimeNanos)) {
-                expiredLeases.add(lease);
-            }
-        }
-
-        return expiredLeases;
-    }
-
-    /**
-     * Compute the number of leases I should try to take based on the state of the system.
-     * 
-     * @param allLeases map of shardId to lease containing all leases
-     * @param expiredLeases list of leases we determined to be expired
-     * @return set of leases to take.
-     */
-    private Set<T> computeLeasesToTake(List<T> expiredLeases) {
-        Map<String, Integer> leaseCounts = computeLeaseCounts(expiredLeases);
-        Set<T> leasesToTake = new HashSet<T>();
-        IMetricsScope metrics = MetricsHelper.getMetricsScope();
-
-        int numLeases = allLeases.size();
-        int numWorkers = leaseCounts.size();
-
-        if (numLeases == 0) {
-            // If there are no leases, I shouldn't try to take any.
-            return leasesToTake;
-        }
-
-        int target;
-        if (numWorkers >= numLeases) {
-            // If we have n leases and n or more workers, each worker can have up to 1 lease, including myself.
-            target = 1;
-        } else {
-            /*
-             * numWorkers must be < numLeases.
-             * 
-             * Our target for each worker is numLeases / numWorkers (+1 if numWorkers doesn't evenly divide numLeases)
-             */
-            target = numLeases / numWorkers + (numLeases % numWorkers == 0 ? 0 : 1);
-
-            // Spill over is the number of leases this worker should have claimed, but did not because it would
-            // exceed the max allowed for this worker.
-            int leaseSpillover = Math.max(0, target - maxLeasesForWorker);
-            if (target > maxLeasesForWorker) {
-                log.warn("Worker {} target is {} leases and maxLeasesForWorker is {}."
-                        + " Resetting target to {}, lease spillover is {}. "
-                        + " Note that some shards may not be processed if no other workers are able to pick them up.",
-                        workerIdentifier,
-                        target,
-                        maxLeasesForWorker,
-                        maxLeasesForWorker,
-                        leaseSpillover);
-                target = maxLeasesForWorker;
-            }
-            metrics.addData("LeaseSpillover", leaseSpillover, StandardUnit.Count, MetricsLevel.SUMMARY);
-        }
-
-        int myCount = leaseCounts.get(workerIdentifier);
-        int numLeasesToReachTarget = target - myCount;
-
-        if (numLeasesToReachTarget <= 0) {
-            // If we don't need anything, return the empty set.
-            return leasesToTake;
-        }
-
-        // Shuffle expiredLeases so workers don't all try to contend for the same leases.
-        Collections.shuffle(expiredLeases);
-
-        int originalExpiredLeasesSize = expiredLeases.size();
-        if (expiredLeases.size() > 0) {
-            // If we have expired leases, get up to <needed> leases from expiredLeases
-            for (; numLeasesToReachTarget > 0 && expiredLeases.size() > 0; numLeasesToReachTarget--) {
-                leasesToTake.add(expiredLeases.remove(0));
-            }
-        } else {
-            // If there are no expired leases and we need a lease, consider stealing.
-            List<T> leasesToSteal = chooseLeasesToSteal(leaseCounts, numLeasesToReachTarget, target);
-            for (T leaseToSteal : leasesToSteal) {
-                log.info("Worker {} needed {} leases but none were expired, so it will steal lease {} from {}",
-                        workerIdentifier,
-                        numLeasesToReachTarget,
-                        leaseToSteal.getLeaseKey(),
-                        leaseToSteal.getLeaseOwner());
-                leasesToTake.add(leaseToSteal);
-            }
-        }
-
-        if (!leasesToTake.isEmpty()) {
-            log.info("Worker {} saw {} total leases, {} available leases, {} "
-                    + "workers. Target is {} leases, I have {} leases, I will take {} leases",
-                    workerIdentifier,
-                    numLeases,
-                    originalExpiredLeasesSize,
-                    numWorkers,
-                    target,
-                    myCount,
-                    leasesToTake.size());
-        }
-
-        metrics.addData("TotalLeases", numLeases, StandardUnit.Count, MetricsLevel.DETAILED);
-        metrics.addData("ExpiredLeases", originalExpiredLeasesSize, StandardUnit.Count, MetricsLevel.SUMMARY);
-        metrics.addData("NumWorkers", numWorkers, StandardUnit.Count, MetricsLevel.SUMMARY);
-        metrics.addData("NeededLeases", numLeasesToReachTarget, StandardUnit.Count, MetricsLevel.DETAILED);
-        metrics.addData("LeasesToTake", leasesToTake.size(), StandardUnit.Count, MetricsLevel.DETAILED);
-
-        return leasesToTake;
-    }
-
-    /**
-     * Choose leases to steal by randomly selecting one or more (up to max) from the most loaded worker.
-     * Stealing rules:
-     * 
-     * Steal up to maxLeasesToStealAtOneTime leases from the most loaded worker if
-     * a) he has > target leases and I need >= 1 leases : steal min(leases needed, maxLeasesToStealAtOneTime)
-     * b) he has == target leases and I need > 1 leases : steal 1
-     * 
-     * @param leaseCounts map of workerIdentifier to lease count
-     * @param needed # of leases needed to reach the target leases for the worker
-     * @param target target # of leases per worker
-     * @return Leases to steal, or empty list if we should not steal
-     */
-    private List<T> chooseLeasesToSteal(Map<String, Integer> leaseCounts, int needed, int target) {
-        List<T> leasesToSteal = new ArrayList<>();
-
-        Entry<String, Integer> mostLoadedWorker = null;
-        // Find the most loaded worker
-        for (Entry<String, Integer> worker : leaseCounts.entrySet()) {
-            if (mostLoadedWorker == null || mostLoadedWorker.getValue() < worker.getValue()) {
-                mostLoadedWorker = worker;
-            }
-        }
-
-        int numLeasesToSteal = 0;
-        if ((mostLoadedWorker.getValue() >= target) && (needed > 0)) {
-            int leasesOverTarget = mostLoadedWorker.getValue() - target;
-            numLeasesToSteal = Math.min(needed, leasesOverTarget);
-            // steal 1 if we need > 1 and max loaded worker has target leases.
-            if ((needed > 1) && (numLeasesToSteal == 0)) {
-                numLeasesToSteal = 1;
-            }
-            numLeasesToSteal = Math.min(numLeasesToSteal, maxLeasesToStealAtOneTime);
-        }
-
-        if (numLeasesToSteal <= 0) {
-            if (log.isDebugEnabled()) {
-                log.debug(String.format("Worker %s not stealing from most loaded worker %s.  He has %d,"
-                        + " target is %d, and I need %d",
-                        workerIdentifier,
-                        mostLoadedWorker.getKey(),
-                        mostLoadedWorker.getValue(),
-                        target,
-                        needed));
-            }
-            return leasesToSteal;
-        } else {
-            if (log.isDebugEnabled()) {
-                log.debug("Worker {} will attempt to steal {} leases from most loaded worker {}. "
-                        + " He has {} leases, target is {}, I need {}, maxLeasesToSteatAtOneTime is {}.",
-                        workerIdentifier,
-                        numLeasesToSteal,
-                        mostLoadedWorker.getKey(),
-                        mostLoadedWorker.getValue(),
-                        target,
-                        needed,
-                        maxLeasesToStealAtOneTime);
-            }
-        }
-
-        String mostLoadedWorkerIdentifier = mostLoadedWorker.getKey();
-        List<T> candidates = new ArrayList<T>();
-        // Collect leases belonging to that worker
-        for (T lease : allLeases.values()) {
-            if (mostLoadedWorkerIdentifier.equals(lease.getLeaseOwner())) {
-                candidates.add(lease);
-            }
-        }
-
-        // Return random ones
-        Collections.shuffle(candidates);
-        int toIndex = Math.min(candidates.size(), numLeasesToSteal);
-        leasesToSteal.addAll(candidates.subList(0, toIndex));
-
-        return leasesToSteal;
-    }
-
-    /**
-     * Count leases by host. Always includes myself, but otherwise only includes hosts that are currently holding
-     * leases.
-     * 
-     * @param expiredLeases list of leases that are currently expired
-     * @return map of workerIdentifier to lease count
-     */
-    private Map<String, Integer> computeLeaseCounts(List<T> expiredLeases) {
-        Map<String, Integer> leaseCounts = new HashMap<String, Integer>();
-
-        // Compute the number of leases per worker by looking through allLeases and ignoring leases that have expired.
-        for (T lease : allLeases.values()) {
-            if (!expiredLeases.contains(lease)) {
-                String leaseOwner = lease.getLeaseOwner();
-                Integer oldCount = leaseCounts.get(leaseOwner);
-                if (oldCount == null) {
-                    leaseCounts.put(leaseOwner, 1);
-                } else {
-                    leaseCounts.put(leaseOwner, oldCount + 1);
-                }
-            }
-        }
-
-        // If I have no leases, I wasn't represented in leaseCounts. Let's fix that.
-        Integer myCount = leaseCounts.get(workerIdentifier);
-        if (myCount == null) {
-            myCount = 0;
-            leaseCounts.put(workerIdentifier, myCount);
-        }
-
-        return leaseCounts;
-    }
-
-    /**
-     * {@inheritDoc}
-     */
-    @Override
-    public String getWorkerIdentifier() {
-        return workerIdentifier;
-    }
 }

amazon-kinesis-client/src/main/java/software/amazon/kinesis/lifecycle/InitializationInput.java

@@ -14,12 +14,12 @@
  */
 package software.amazon.kinesis.lifecycle;
 
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.RecordProcessor;
 import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
 
 /**
  * Container for the parameters to the IRecordProcessor's
- * {@link IRecordProcessor#initialize(InitializationInput
+ * {@link RecordProcessor#initialize(InitializationInput
  * initializationInput) initialize} method.
  */
 public class InitializationInput {

amazon-kinesis-client/src/main/java/software/amazon/kinesis/lifecycle/InitializeTask.java

@@ -17,10 +17,10 @@ package software.amazon.kinesis.lifecycle;
 import com.amazonaws.services.kinesis.clientlibrary.lib.worker.InitialPositionInStreamExtended;
 import lombok.NonNull;
 import lombok.RequiredArgsConstructor;
-import software.amazon.kinesis.coordinator.RecordProcessorCheckpointer;
+import software.amazon.kinesis.checkpoint.RecordProcessorCheckpointer;
 import software.amazon.kinesis.leases.ShardInfo;
-import software.amazon.kinesis.processor.ICheckpoint;
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.Checkpointer;
+import software.amazon.kinesis.processor.RecordProcessor;
 import software.amazon.kinesis.checkpoint.Checkpoint;
 import software.amazon.kinesis.retrieval.GetRecordsCache;
 import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
@@ -40,9 +40,9 @@ public class InitializeTask implements ITask {
     @NonNull
     private final ShardInfo shardInfo;
     @NonNull
-    private final IRecordProcessor recordProcessor;
+    private final RecordProcessor recordProcessor;
     @NonNull
-    private final ICheckpoint checkpoint;
+    private final Checkpointer checkpoint;
     @NonNull
     private final RecordProcessorCheckpointer recordProcessorCheckpointer;
     @NonNull
@@ -69,7 +69,7 @@ public class InitializeTask implements ITask {
         try {
             log.debug("Initializing ShardId {}", shardInfo);
             Checkpoint initialCheckpointObject = checkpoint.getCheckpointObject(shardInfo.shardId());
-            ExtendedSequenceNumber initialCheckpoint = initialCheckpointObject.getCheckpoint();
+            ExtendedSequenceNumber initialCheckpoint = initialCheckpointObject.checkpoint();
 
             cache.start(initialCheckpoint, initialPositionInStream);
 
@@ -80,7 +80,7 @@ public class InitializeTask implements ITask {
             final InitializationInput initializationInput = new InitializationInput()
                 .withShardId(shardInfo.shardId())
                 .withExtendedSequenceNumber(initialCheckpoint)
-                .withPendingCheckpointSequenceNumber(initialCheckpointObject.getPendingCheckpoint());
+                .withPendingCheckpointSequenceNumber(initialCheckpointObject.pendingCheckpoint());
             final long recordProcessorStartTimeMillis = System.currentTimeMillis();
             try {
                 recordProcessor.initialize(initializationInput);

amazon-kinesis-client/src/main/java/software/amazon/kinesis/lifecycle/ProcessRecordsInput.java

@@ -23,11 +23,11 @@ import software.amazon.kinesis.processor.IRecordProcessorCheckpointer;
 import com.amazonaws.services.kinesis.model.Record;
 
 import lombok.Getter;
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.RecordProcessor;
 
 /**
  * Container for the parameters to the IRecordProcessor's
- * {@link IRecordProcessor#processRecords(
+ * {@link RecordProcessor#processRecords(
  * ProcessRecordsInput processRecordsInput) processRecords} method.
  */
 @AllArgsConstructor

amazon-kinesis-client/src/main/java/software/amazon/kinesis/lifecycle/ProcessTask.java

@@ -19,13 +19,13 @@ import com.amazonaws.services.kinesis.model.Shard;
 import lombok.NonNull;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
-import software.amazon.kinesis.coordinator.RecordProcessorCheckpointer;
+import software.amazon.kinesis.checkpoint.RecordProcessorCheckpointer;
 import software.amazon.kinesis.leases.LeaseManagerProxy;
 import software.amazon.kinesis.leases.ShardInfo;
 import software.amazon.kinesis.metrics.IMetricsScope;
 import software.amazon.kinesis.metrics.MetricsHelper;
 import software.amazon.kinesis.metrics.MetricsLevel;
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.RecordProcessor;
 import software.amazon.kinesis.retrieval.GetRecordsCache;
 import software.amazon.kinesis.retrieval.ThrottlingReporter;
 import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
@@ -42,7 +42,7 @@ public class ProcessTask implements ITask {
     private static final String RECORD_PROCESSOR_PROCESS_RECORDS_METRIC = "RecordProcessor.processRecords";
 
     private final ShardInfo shardInfo;
-    private final IRecordProcessor recordProcessor;
+    private final RecordProcessor recordProcessor;
     private final RecordProcessorCheckpointer recordProcessorCheckpointer;
     private final TaskType taskType = TaskType.PROCESS;
     private final long backoffTimeMillis;
@@ -73,7 +73,7 @@ public class ProcessTask implements ITask {
     }
 
     public ProcessTask(@NonNull final ShardInfo shardInfo,
-                       @NonNull final IRecordProcessor recordProcessor,
+                       @NonNull final RecordProcessor recordProcessor,
                        @NonNull final RecordProcessorCheckpointer recordProcessorCheckpointer,
                        final long backoffTimeMillis,
                        final boolean skipShardSyncAtWorkerInitializationIfLeasesExist,

amazon-kinesis-client/src/main/java/software/amazon/kinesis/lifecycle/RecordProcessorShim.java

@@ -20,14 +20,14 @@ import software.amazon.kinesis.lifecycle.events.RecordsReceived;
 import software.amazon.kinesis.lifecycle.events.ShardCompleted;
 import software.amazon.kinesis.lifecycle.events.ShutdownRequested;
 import software.amazon.kinesis.lifecycle.events.Started;
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.RecordProcessor;
 import software.amazon.kinesis.processor.IRecordProcessorCheckpointer;
-import software.amazon.kinesis.processor.IShutdownNotificationAware;
+import software.amazon.kinesis.processor.ShutdownNotificationAware;
 
 @RequiredArgsConstructor
 public class RecordProcessorShim implements RecordProcessorLifecycle {
 
-    private final IRecordProcessor delegate;
+    private final RecordProcessor delegate;
 
     @Override
     public void started(Started started) {
@@ -60,8 +60,8 @@ public class RecordProcessorShim implements RecordProcessorLifecycle {
 
     @Override
     public void shutdownRequested(ShutdownRequested shutdownRequested) {
-        if (delegate instanceof IShutdownNotificationAware) {
-            IShutdownNotificationAware aware = (IShutdownNotificationAware)delegate;
+        if (delegate instanceof ShutdownNotificationAware) {
+            ShutdownNotificationAware aware = (ShutdownNotificationAware)delegate;
             aware.shutdownRequested(shutdownRequested.getCheckpointer());
         }
     }

amazon-kinesis-client/src/main/java/software/amazon/kinesis/lifecycle/ShardConsumer.java

@@ -34,16 +34,15 @@ import lombok.RequiredArgsConstructor;
 import lombok.Synchronized;
 import lombok.experimental.Accessors;
 import lombok.extern.slf4j.Slf4j;
-import software.amazon.kinesis.coordinator.RecordProcessorCheckpointer;
+import software.amazon.kinesis.checkpoint.RecordProcessorCheckpointer;
 import software.amazon.kinesis.leases.ILeaseManager;
 import software.amazon.kinesis.leases.KinesisClientLease;
-import software.amazon.kinesis.leases.LeaseManager;
 import software.amazon.kinesis.leases.LeaseManagerProxy;
 import software.amazon.kinesis.leases.ShardInfo;
 import software.amazon.kinesis.metrics.IMetricsFactory;
 import software.amazon.kinesis.metrics.MetricsCollectingTaskDecorator;
-import software.amazon.kinesis.processor.ICheckpoint;
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.Checkpointer;
+import software.amazon.kinesis.processor.RecordProcessor;
 import software.amazon.kinesis.retrieval.GetRecordsCache;
 
 /**
@@ -67,9 +66,9 @@ public class ShardConsumer {
     @NonNull
     private final GetRecordsCache getRecordsCache;
     @NonNull
-    private final IRecordProcessor recordProcessor;
+    private final RecordProcessor recordProcessor;
     @NonNull
-    private final ICheckpoint checkpoint;
+    private final Checkpointer checkpoint;
     @NonNull
     private final RecordProcessorCheckpointer recordProcessorCheckpointer;
     private final long parentShardPollIntervalMillis;

amazon-kinesis-client/src/main/java/software/amazon/kinesis/lifecycle/ShardConsumerShutdownNotification.java

@@ -16,7 +16,7 @@ package software.amazon.kinesis.lifecycle;
 
 import java.util.concurrent.CountDownLatch;
 
-import software.amazon.kinesis.processor.IShutdownNotificationAware;
+import software.amazon.kinesis.processor.ShutdownNotificationAware;
 import software.amazon.kinesis.leases.KinesisClientLease;
 import software.amazon.kinesis.leases.LeaseCoordinator;
 
@@ -43,7 +43,7 @@ public class ShardConsumerShutdownNotification implements ShutdownNotification {
      *            the lease that this shutdown request will free once initial shutdown is complete
      * @param notificationCompleteLatch
      *            used to inform the caller once the
-     *            {@link IShutdownNotificationAware} object has been
+     *            {@link ShutdownNotificationAware} object has been
      *            notified of the shutdown request.
      * @param shutdownCompleteLatch
      *            used to inform the caller once the record processor is fully shutdown

amazon-kinesis-client/src/main/java/software/amazon/kinesis/lifecycle/ShutdownInput.java

@@ -16,12 +16,12 @@ package software.amazon.kinesis.lifecycle;
 
 import lombok.Data;
 import lombok.experimental.Accessors;
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.RecordProcessor;
 import software.amazon.kinesis.processor.IRecordProcessorCheckpointer;
 
 /**
  * Container for the parameters to the IRecordProcessor's
- * {@link IRecordProcessor#shutdown(ShutdownInput
+ * {@link RecordProcessor#shutdown(ShutdownInput
  * shutdownInput) shutdown} method.
  */
 @Data

amazon-kinesis-client/src/main/java/software/amazon/kinesis/lifecycle/ShutdownNotification.java

@@ -14,7 +14,7 @@
  */
 package software.amazon.kinesis.lifecycle;
 
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.RecordProcessor;
 
 /**
  * A shutdown request to the ShardConsumer
@@ -29,7 +29,7 @@ public interface ShutdownNotification {
 
     /**
      * Used to indicate that the record processor has completed the call to
-     * {@link IRecordProcessor#shutdown(ShutdownInput)} has
+     * {@link RecordProcessor#shutdown(ShutdownInput)} has
      * completed.
      */
     void shutdownComplete();

amazon-kinesis-client/src/main/java/software/amazon/kinesis/lifecycle/ShutdownNotificationTask.java

@@ -19,8 +19,8 @@ import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
 import software.amazon.kinesis.leases.ShardInfo;
 import software.amazon.kinesis.processor.IRecordProcessorCheckpointer;
-import software.amazon.kinesis.processor.IRecordProcessor;
-import software.amazon.kinesis.processor.IShutdownNotificationAware;
+import software.amazon.kinesis.processor.RecordProcessor;
+import software.amazon.kinesis.processor.ShutdownNotificationAware;
 
 /**
  * Notifies record processor of incoming shutdown request, and gives them a chance to checkpoint.
@@ -28,7 +28,7 @@ import software.amazon.kinesis.processor.IShutdownNotificationAware;
 @RequiredArgsConstructor(access = AccessLevel.PACKAGE)
 @Slf4j
 public class ShutdownNotificationTask implements ITask {
-    private final IRecordProcessor recordProcessor;
+    private final RecordProcessor recordProcessor;
     private final IRecordProcessorCheckpointer recordProcessorCheckpointer;
     private final ShutdownNotification shutdownNotification;
 //    TODO: remove if not used
@@ -38,8 +38,8 @@ public class ShutdownNotificationTask implements ITask {
     @Override
     public TaskResult call() {
         try {
-            if (recordProcessor instanceof IShutdownNotificationAware) {
-                IShutdownNotificationAware shutdownNotificationAware = (IShutdownNotificationAware) recordProcessor;
+            if (recordProcessor instanceof ShutdownNotificationAware) {
+                ShutdownNotificationAware shutdownNotificationAware = (ShutdownNotificationAware) recordProcessor;
                 try {
                     shutdownNotificationAware.shutdownRequested(recordProcessorCheckpointer);
                 } catch (Exception ex) {

amazon-kinesis-client/src/main/java/software/amazon/kinesis/lifecycle/ShutdownReason.java

@@ -17,7 +17,7 @@ package software.amazon.kinesis.lifecycle;
 import lombok.AccessLevel;
 import lombok.Getter;
 import lombok.experimental.Accessors;
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.RecordProcessor;
 
 import static software.amazon.kinesis.lifecycle.ConsumerStates.ConsumerState;
 import static software.amazon.kinesis.lifecycle.ConsumerStates.ShardConsumerState;
@@ -50,7 +50,7 @@ public enum ShutdownReason {
     /**
      * Indicates that the entire application is being shutdown, and if desired the record processor will be given a
      * final chance to checkpoint. This state will not trigger a direct call to
-     * {@link IRecordProcessor#shutdown(ShutdownInput)}, but
+     * {@link RecordProcessor#shutdown(ShutdownInput)}, but
      * instead depend on a different interface for backward compatibility.
      */
     REQUESTED(1, ShardConsumerState.SHUTDOWN_REQUESTED.getConsumerState());

amazon-kinesis-client/src/main/java/software/amazon/kinesis/lifecycle/ShutdownTask.java

@@ -20,7 +20,7 @@ import com.google.common.annotations.VisibleForTesting;
 import lombok.NonNull;
 import lombok.RequiredArgsConstructor;
 import lombok.extern.slf4j.Slf4j;
-import software.amazon.kinesis.coordinator.RecordProcessorCheckpointer;
+import software.amazon.kinesis.checkpoint.RecordProcessorCheckpointer;
 import software.amazon.kinesis.leases.ILeaseManager;
 import software.amazon.kinesis.leases.KinesisClientLease;
 import software.amazon.kinesis.leases.LeaseManagerProxy;
@@ -28,7 +28,7 @@ import software.amazon.kinesis.leases.ShardInfo;
 import software.amazon.kinesis.leases.ShardSyncer;
 import software.amazon.kinesis.metrics.MetricsHelper;
 import software.amazon.kinesis.metrics.MetricsLevel;
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.RecordProcessor;
 import software.amazon.kinesis.retrieval.GetRecordsCache;
 import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
 
@@ -45,7 +45,7 @@ public class ShutdownTask implements ITask {
     @NonNull
     private final LeaseManagerProxy leaseManagerProxy;
     @NonNull
-    private final IRecordProcessor recordProcessor;
+    private final RecordProcessor recordProcessor;
     @NonNull
     private final RecordProcessorCheckpointer recordProcessorCheckpointer;
     @NonNull

amazon-kinesis-client/src/main/java/software/amazon/kinesis/metrics/MetricsConfig.java

@@ -51,7 +51,6 @@ public class MetricsConfig {
      *
      * @return {@link AmazonCloudWatch}
      */
-    @NonNull
     private final AmazonCloudWatch amazonCloudWatch;
 
     /**

amazon-kinesis-client/src/main/java/software/amazon/kinesis/processor/Checkpointer.java

@@ -21,7 +21,7 @@ import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
 /**
  * Interface for checkpoint trackers.
  */
-public interface ICheckpoint {
+public interface Checkpointer {
 
     /**
      * Record a checkpoint for a shard (e.g. sequence and subsequence numbers of last record processed 

amazon-kinesis-client/src/main/java/software/amazon/kinesis/processor/IPreparedCheckpointer.java

@@ -30,7 +30,7 @@ public interface IPreparedCheckpointer {
     /**
      * @return sequence number of pending checkpoint
      */
-    ExtendedSequenceNumber getPendingCheckpoint();
+    ExtendedSequenceNumber pendingCheckpoint();
 
     /**
      * This method will record a pending checkpoint.

amazon-kinesis-client/src/main/java/software/amazon/kinesis/processor/ProcessorFactory.java

@@ -19,5 +19,5 @@ package software.amazon.kinesis.processor;
  *
  */
 public interface ProcessorFactory {
-    IRecordProcessor createRecordProcessor();
+    RecordProcessor createRecordProcessor();
 }

amazon-kinesis-client/src/main/java/software/amazon/kinesis/processor/RecordProcessor.java

@@ -23,7 +23,7 @@ import software.amazon.kinesis.lifecycle.ShutdownReason;
  * The Amazon Kinesis Client Library will instantiate record processors to process data records fetched from Amazon
  * Kinesis.
  */
-public interface IRecordProcessor {
+public interface RecordProcessor {
 
     /**
      * Invoked by the Amazon Kinesis Client Library before data records are delivered to the RecordProcessor instance

amazon-kinesis-client/src/main/java/software/amazon/kinesis/processor/RecordProcessorFactory.java

@@ -19,13 +19,13 @@ package software.amazon.kinesis.processor;
  * The Amazon Kinesis Client Library will use this to instantiate a record processor per shard.
  * Clients may choose to create separate instantiations, or re-use instantiations.
  */
-public interface IRecordProcessorFactory {
+public interface RecordProcessorFactory {
 
     /**
      * Returns a record processor to be used for processing data records for a (assigned) shard.
      * 
      * @return Returns a processor object.
      */
-    IRecordProcessor createProcessor();
+    RecordProcessor createProcessor();
 
 }

amazon-kinesis-client/src/main/java/software/amazon/kinesis/processor/ShutdownNotificationAware.java

@@ -19,7 +19,7 @@ import software.amazon.kinesis.processor.IRecordProcessorCheckpointer;
 /**
  * Allows a record processor to indicate it's aware of requested shutdowns, and handle the request.
  */
-public interface IShutdownNotificationAware {
+public interface ShutdownNotificationAware {
 
     /**
      * Called when the worker has been requested to shutdown, and gives the record processor a chance to checkpoint.

amazon-kinesis-client/src/main/java/software/amazon/kinesis/retrieval/SynchronousBlockingRetrievalFactory.java

@@ -26,11 +26,6 @@ import software.amazon.kinesis.metrics.IMetricsFactory;
  */
 @Data
 public class SynchronousBlockingRetrievalFactory implements RetrievalFactory {
-//    Need to remove this. Has no use any longer.
-    private static final long DESCRIBE_STREAM_BACKOFF_TIME_IN_MILLIS = 1500L;
-//    Need to remove this. Has no use any longer.
-    private static final int MAX_DESCRIBE_STREAM_RETRY_ATTEMPTS = 50;
-
     @NonNull
     private final String streamName;
     @NonNull

amazon-kinesis-client/src/main/java/software/amazon/kinesis/retrieval/SynchronousPrefetchingRetrievalFactory.java

@@ -0,0 +1,60 @@
+/*
+ *  Copyright 2018 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ *  Licensed under the Amazon Software License (the "License").
+ *  You may not use this file except in compliance with the License.
+ *  A copy of the License is located at
+ *
+ *  http://aws.amazon.com/asl/
+ *
+ *  or in the "license" file accompanying this file. This file is distributed
+ *  on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
+ *  express or implied. See the License for the specific language governing
+ *  permissions and limitations under the License.
+ */
+
+package software.amazon.kinesis.retrieval;
+
+import com.amazonaws.services.kinesis.AmazonKinesis;
+import lombok.NonNull;
+import lombok.RequiredArgsConstructor;
+import software.amazon.kinesis.leases.ShardInfo;
+import software.amazon.kinesis.metrics.IMetricsFactory;
+
+import java.util.concurrent.ExecutorService;
+
+/**
+ *
+ */
+@RequiredArgsConstructor
+public class SynchronousPrefetchingRetrievalFactory implements RetrievalFactory {
+    @NonNull
+    private final String streamName;
+    @NonNull
+    private final AmazonKinesis amazonKinesis;
+    private final int maxRecords;
+    private final int maxPendingProcessRecordsInput;
+    private final int maxByteSize;
+    private final int maxRecordsCount;
+    private final int maxRecordsPerCall;
+    @NonNull
+    private final ExecutorService executorService;
+    private final long idleMillisBetweenCalls;
+    @NonNull
+    private final IMetricsFactory metricsFactory;
+
+
+
+    @Override
+    public GetRecordsRetrievalStrategy createGetRecordsRetrievalStrategy(final ShardInfo shardInfo) {
+        return new SynchronousGetRecordsRetrievalStrategy(
+                new KinesisDataFetcher(amazonKinesis, streamName, shardInfo.shardId(), maxRecords));
+    }
+
+    @Override
+    public GetRecordsCache createGetRecordsCache(final ShardInfo shardInfo) {
+        return new PrefetchGetRecordsCache(maxPendingProcessRecordsInput, maxByteSize, maxRecordsCount,
+                maxRecordsPerCall, createGetRecordsRetrievalStrategy(shardInfo), executorService,
+                idleMillisBetweenCalls, metricsFactory, "Prefetching", shardInfo.shardId());
+    }
+}

amazon-kinesis-client/src/test/java/com/amazonaws/services/kinesis/clientlibrary/lib/checkpoint/CheckpointImplTestBase.java

@@ -21,7 +21,7 @@ import org.junit.Before;
 import org.junit.BeforeClass;
 import org.junit.Test;
 
-import software.amazon.kinesis.processor.ICheckpoint;
+import software.amazon.kinesis.processor.Checkpointer;
 import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
 import software.amazon.kinesis.metrics.MetricsHelper;
 import software.amazon.kinesis.metrics.NullMetricsFactory;
@@ -34,7 +34,7 @@ public abstract class CheckpointImplTestBase {
 
     protected final String startingSequenceNumber = "0001000";
     protected final String testConcurrencyToken = "testToken";
-    protected ICheckpoint checkpoint;
+    protected Checkpointer checkpoint;
 
     /**
      * @throws java.lang.Exception
@@ -107,8 +107,8 @@ public abstract class CheckpointImplTestBase {
     	ExtendedSequenceNumber extendedSequenceNumber = new ExtendedSequenceNumber(checkpointValue);
         checkpoint.setCheckpoint(shardId, new ExtendedSequenceNumber(checkpointValue), concurrencyToken);
         Assert.assertEquals(extendedSequenceNumber, checkpoint.getCheckpoint(shardId));
-        Assert.assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        Assert.assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        Assert.assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        Assert.assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
     }
 
     @Test
@@ -123,8 +123,8 @@ public abstract class CheckpointImplTestBase {
         checkpoint.prepareCheckpoint(shardId, new ExtendedSequenceNumber(pendingCheckpointValue), testConcurrencyToken);
 
         Assert.assertEquals(extendedCheckpointNumber, checkpoint.getCheckpoint(shardId));
-        Assert.assertEquals(extendedCheckpointNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        Assert.assertEquals(extendedPendingCheckpointNumber, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        Assert.assertEquals(extendedCheckpointNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        Assert.assertEquals(extendedPendingCheckpointNumber, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
     }
 
     @Test
@@ -139,8 +139,8 @@ public abstract class CheckpointImplTestBase {
             ExtendedSequenceNumber extendedSequenceNumber = new ExtendedSequenceNumber(sequenceNumber);
             checkpoint.prepareCheckpoint(shardId, new ExtendedSequenceNumber(sequenceNumber), testConcurrencyToken);
             Assert.assertEquals(extendedCheckpointNumber, checkpoint.getCheckpoint(shardId));
-            Assert.assertEquals(extendedCheckpointNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-            Assert.assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+            Assert.assertEquals(extendedCheckpointNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+            Assert.assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
         }
     }
 
@@ -155,20 +155,20 @@ public abstract class CheckpointImplTestBase {
         ExtendedSequenceNumber extendedCheckpointNumber = new ExtendedSequenceNumber(checkpointValue);
         checkpoint.setCheckpoint(shardId, new ExtendedSequenceNumber(checkpointValue), concurrencyToken);
         Assert.assertEquals(extendedCheckpointNumber, checkpoint.getCheckpoint(shardId));
-        Assert.assertEquals(extendedCheckpointNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        Assert.assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        Assert.assertEquals(extendedCheckpointNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        Assert.assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         // prepare checkpoint
         ExtendedSequenceNumber extendedPendingCheckpointNumber = new ExtendedSequenceNumber(pendingCheckpointValue);
         checkpoint.prepareCheckpoint(shardId, new ExtendedSequenceNumber(pendingCheckpointValue), concurrencyToken);
         Assert.assertEquals(extendedCheckpointNumber, checkpoint.getCheckpoint(shardId));
-        Assert.assertEquals(extendedCheckpointNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        Assert.assertEquals(extendedPendingCheckpointNumber, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        Assert.assertEquals(extendedCheckpointNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        Assert.assertEquals(extendedPendingCheckpointNumber, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         // do checkpoint
         checkpoint.setCheckpoint(shardId, new ExtendedSequenceNumber(pendingCheckpointValue), concurrencyToken);
         Assert.assertEquals(extendedPendingCheckpointNumber, checkpoint.getCheckpoint(shardId));
-        Assert.assertEquals(extendedPendingCheckpointNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        Assert.assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        Assert.assertEquals(extendedPendingCheckpointNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        Assert.assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
     }
 }

amazon-kinesis-client/src/test/java/com/amazonaws/services/kinesis/clientlibrary/lib/checkpoint/InMemoryCheckpointer.java

@@ -19,7 +19,7 @@ import java.util.Map;
 
 import com.amazonaws.services.kinesis.clientlibrary.exceptions.KinesisClientLibException;
 import software.amazon.kinesis.checkpoint.Checkpoint;
-import software.amazon.kinesis.processor.ICheckpoint;
+import software.amazon.kinesis.processor.Checkpointer;
 import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
 
 import lombok.extern.slf4j.Slf4j;
@@ -28,7 +28,7 @@ import lombok.extern.slf4j.Slf4j;
  * Everything is stored in memory and there is no fault-tolerance.
  */
 @Slf4j
-public class InMemoryCheckpointImpl implements ICheckpoint {
+public class InMemoryCheckpointer implements Checkpointer {
     private Map<String, ExtendedSequenceNumber> checkpoints = new HashMap<>();
     private Map<String, ExtendedSequenceNumber> flushpoints = new HashMap<>();
     private Map<String, ExtendedSequenceNumber> pendingCheckpoints = new HashMap<>();
@@ -39,7 +39,7 @@ public class InMemoryCheckpointImpl implements ICheckpoint {
      *
      * @param startingSequenceNumber Initial checkpoint will be set to this sequenceNumber (for all shards).
      */
-    public InMemoryCheckpointImpl(String startingSequenceNumber) {
+    public InMemoryCheckpointer(String startingSequenceNumber) {
         super();
         this.startingSequenceNumber = startingSequenceNumber;
     }

amazon-kinesis-client/src/test/java/com/amazonaws/services/kinesis/clientlibrary/lib/checkpoint/InMemoryCheckpointerTest.java

@@ -20,11 +20,11 @@ import org.junit.Before;
 /**
  * Test the InMemoryCheckpointImplTest class.
  */
-public class InMemoryCheckpointImplTest extends CheckpointImplTestBase {
+public class InMemoryCheckpointerTest extends CheckpointImplTestBase {
     /**
      * Constructor.
      */
-    public InMemoryCheckpointImplTest() {
+    public InMemoryCheckpointerTest() {
         super();
     }
     /**
@@ -32,7 +32,7 @@ public class InMemoryCheckpointImplTest extends CheckpointImplTestBase {
      */
     @Before
     public void setUp() throws Exception {
-        checkpoint = new InMemoryCheckpointImpl(startingSequenceNumber);
+        checkpoint = new InMemoryCheckpointer(startingSequenceNumber);
     }
 
 }

amazon-kinesis-client/src/test/java/software/amazon/kinesis/checkpoint/PreparedCheckpointerTest.java

@@ -14,8 +14,6 @@
  */
 package software.amazon.kinesis.checkpoint;
 
-import software.amazon.kinesis.checkpoint.DoesNothingPreparedCheckpointer;
-import software.amazon.kinesis.checkpoint.PreparedCheckpointer;
 import software.amazon.kinesis.processor.IPreparedCheckpointer;
 import software.amazon.kinesis.processor.IRecordProcessorCheckpointer;
 import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
@@ -26,13 +24,13 @@ import org.mockito.Mockito;
 public class PreparedCheckpointerTest {
 
     /**
-     * This test verifies the relationship between the constructor and getPendingCheckpoint.
+     * This test verifies the relationship between the constructor and pendingCheckpoint.
      */
     @Test
     public void testGetSequenceNumber() {
         ExtendedSequenceNumber sn = new ExtendedSequenceNumber("sn");
         IPreparedCheckpointer checkpointer = new PreparedCheckpointer(sn, null);
-        Assert.assertEquals(sn, checkpointer.getPendingCheckpoint());
+        Assert.assertEquals(sn, checkpointer.pendingCheckpoint());
     }
 
     /**
@@ -58,7 +56,7 @@ public class PreparedCheckpointerTest {
     public void testDoesNothingPreparedCheckpoint() throws Exception {
         ExtendedSequenceNumber sn = new ExtendedSequenceNumber("sn");
         IPreparedCheckpointer checkpointer = new DoesNothingPreparedCheckpointer(sn);
-        Assert.assertEquals(sn, checkpointer.getPendingCheckpoint());
+        Assert.assertEquals(sn, checkpointer.pendingCheckpoint());
         // nothing happens here
         checkpointer.checkpoint();
     }

amazon-kinesis-client/src/test/java/software/amazon/kinesis/checkpoint/RecordProcessorCheckpointerTest.java

@@ -18,8 +18,6 @@ import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.fail;
-import static org.mockito.Matchers.anyString;
-import static org.mockito.Mockito.doNothing;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.never;
 import static org.mockito.Mockito.verify;
@@ -36,16 +34,15 @@ import org.junit.runner.RunWith;
 import org.mockito.Mock;
 import org.mockito.runners.MockitoJUnitRunner;
 
-import com.amazonaws.services.kinesis.clientlibrary.lib.checkpoint.InMemoryCheckpointImpl;
+import com.amazonaws.services.kinesis.clientlibrary.lib.checkpoint.InMemoryCheckpointer;
 import com.amazonaws.services.kinesis.model.Record;
 
-import software.amazon.kinesis.coordinator.RecordProcessorCheckpointer;
 import software.amazon.kinesis.leases.ShardInfo;
 import software.amazon.kinesis.metrics.IMetricsFactory;
 import software.amazon.kinesis.metrics.IMetricsScope;
 import software.amazon.kinesis.metrics.MetricsHelper;
 import software.amazon.kinesis.metrics.NullMetricsScope;
-import software.amazon.kinesis.processor.ICheckpoint;
+import software.amazon.kinesis.processor.Checkpointer;
 import software.amazon.kinesis.processor.IPreparedCheckpointer;
 import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
 import software.amazon.kinesis.retrieval.kpl.UserRecord;
@@ -58,7 +55,7 @@ public class RecordProcessorCheckpointerTest {
     private String startingSequenceNumber = "13";
     private ExtendedSequenceNumber startingExtendedSequenceNumber = new ExtendedSequenceNumber(startingSequenceNumber);
     private String testConcurrencyToken = "testToken";
-    private ICheckpoint checkpoint;
+    private Checkpointer checkpoint;
     private ShardInfo shardInfo;
     private String streamName = "testStream";
     private String shardId = "shardId-123";
@@ -73,7 +70,7 @@ public class RecordProcessorCheckpointerTest {
      */
     @Before
     public void setup() throws Exception {
-        checkpoint = new InMemoryCheckpointImpl(startingSequenceNumber);
+        checkpoint = new InMemoryCheckpointer(startingSequenceNumber);
         // A real checkpoint will return a checkpoint value after it is initialized.
         checkpoint.setCheckpoint(shardId, startingExtendedSequenceNumber, testConcurrencyToken);
         assertEquals(this.startingExtendedSequenceNumber, checkpoint.getCheckpoint(shardId));
@@ -194,22 +191,22 @@ public class RecordProcessorCheckpointerTest {
         ExtendedSequenceNumber sequenceNumber1 = new ExtendedSequenceNumber("5001");
         processingCheckpointer.largestPermittedCheckpointValue(sequenceNumber1);
         IPreparedCheckpointer preparedCheckpoint = processingCheckpointer.prepareCheckpoint();
-        assertEquals(sequenceNumber1, preparedCheckpoint.getPendingCheckpoint());
-        assertEquals(sequenceNumber1, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(sequenceNumber1, preparedCheckpoint.pendingCheckpoint());
+        assertEquals(sequenceNumber1, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         // Advance checkpoint
         ExtendedSequenceNumber sequenceNumber2 = new ExtendedSequenceNumber("5019");
 
         processingCheckpointer.largestPermittedCheckpointValue(sequenceNumber2);
         preparedCheckpoint = processingCheckpointer.prepareCheckpoint();
-        assertEquals(sequenceNumber2, preparedCheckpoint.getPendingCheckpoint());
-        assertEquals(sequenceNumber2, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(sequenceNumber2, preparedCheckpoint.pendingCheckpoint());
+        assertEquals(sequenceNumber2, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         // Checkpoint using preparedCheckpoint
         preparedCheckpoint.checkpoint();
         assertEquals(sequenceNumber2, checkpoint.getCheckpoint(shardId));
-        assertEquals(sequenceNumber2, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(sequenceNumber2, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
     }
 
     /**
@@ -226,15 +223,15 @@ public class RecordProcessorCheckpointerTest {
         processingCheckpointer.largestPermittedCheckpointValue(extendedSequenceNumber);
         IPreparedCheckpointer preparedCheckpoint = processingCheckpointer.prepareCheckpoint(record);
         assertEquals(startingExtendedSequenceNumber, checkpoint.getCheckpoint(shardId));
-        assertEquals(startingExtendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(extendedSequenceNumber, preparedCheckpoint.getPendingCheckpoint());
-        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(startingExtendedSequenceNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(extendedSequenceNumber, preparedCheckpoint.pendingCheckpoint());
+        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         // Checkpoint using preparedCheckpoint
         preparedCheckpoint.checkpoint();
         assertEquals(extendedSequenceNumber, checkpoint.getCheckpoint(shardId));
-        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
     }
 
     /**
@@ -252,15 +249,15 @@ public class RecordProcessorCheckpointerTest {
         processingCheckpointer.largestPermittedCheckpointValue(extendedSequenceNumber);
         IPreparedCheckpointer preparedCheckpoint = processingCheckpointer.prepareCheckpoint(subRecord);
         assertEquals(startingExtendedSequenceNumber, checkpoint.getCheckpoint(shardId));
-        assertEquals(startingExtendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(extendedSequenceNumber, preparedCheckpoint.getPendingCheckpoint());
-        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(startingExtendedSequenceNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(extendedSequenceNumber, preparedCheckpoint.pendingCheckpoint());
+        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         // Checkpoint using preparedCheckpoint
         preparedCheckpoint.checkpoint();
         assertEquals(extendedSequenceNumber, checkpoint.getCheckpoint(shardId));
-        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
     }
 
     /**
@@ -276,15 +273,15 @@ public class RecordProcessorCheckpointerTest {
         processingCheckpointer.largestPermittedCheckpointValue(extendedSequenceNumber);
         IPreparedCheckpointer preparedCheckpoint = processingCheckpointer.prepareCheckpoint("5035");
         assertEquals(startingExtendedSequenceNumber, checkpoint.getCheckpoint(shardId));
-        assertEquals(startingExtendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(extendedSequenceNumber, preparedCheckpoint.getPendingCheckpoint());
-        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(startingExtendedSequenceNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(extendedSequenceNumber, preparedCheckpoint.pendingCheckpoint());
+        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         // Checkpoint using preparedCheckpoint
         preparedCheckpoint.checkpoint();
         assertEquals(extendedSequenceNumber, checkpoint.getCheckpoint(shardId));
-        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
     }
 
     /**
@@ -300,15 +297,15 @@ public class RecordProcessorCheckpointerTest {
         processingCheckpointer.largestPermittedCheckpointValue(extendedSequenceNumber);
         IPreparedCheckpointer preparedCheckpoint = processingCheckpointer.prepareCheckpoint("5040", 0);
         assertEquals(startingExtendedSequenceNumber, checkpoint.getCheckpoint(shardId));
-        assertEquals(startingExtendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(extendedSequenceNumber, preparedCheckpoint.getPendingCheckpoint());
-        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(startingExtendedSequenceNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(extendedSequenceNumber, preparedCheckpoint.pendingCheckpoint());
+        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         // Checkpoint using preparedCheckpoint
         preparedCheckpoint.checkpoint();
         assertEquals(extendedSequenceNumber, checkpoint.getCheckpoint(shardId));
-        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
     }
 
     /**
@@ -323,15 +320,15 @@ public class RecordProcessorCheckpointerTest {
         processingCheckpointer.largestPermittedCheckpointValue(extendedSequenceNumber);
         IPreparedCheckpointer preparedCheckpoint = processingCheckpointer.prepareCheckpoint(ExtendedSequenceNumber.SHARD_END.getSequenceNumber());
         assertEquals(startingExtendedSequenceNumber, checkpoint.getCheckpoint(shardId));
-        assertEquals(startingExtendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(extendedSequenceNumber, preparedCheckpoint.getPendingCheckpoint());
-        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(startingExtendedSequenceNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(extendedSequenceNumber, preparedCheckpoint.pendingCheckpoint());
+        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         // Checkpoint using preparedCheckpoint
         preparedCheckpoint.checkpoint();
         assertEquals(extendedSequenceNumber, checkpoint.getCheckpoint(shardId));
-        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(extendedSequenceNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
     }
 
 
@@ -347,24 +344,24 @@ public class RecordProcessorCheckpointerTest {
 
         ExtendedSequenceNumber sn1 = new ExtendedSequenceNumber("6010");
         IPreparedCheckpointer firstPreparedCheckpoint = processingCheckpointer.prepareCheckpoint("6010", 0);
-        assertEquals(sn1, firstPreparedCheckpoint.getPendingCheckpoint());
-        assertEquals(sn1, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(sn1, firstPreparedCheckpoint.pendingCheckpoint());
+        assertEquals(sn1, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         ExtendedSequenceNumber sn2 = new ExtendedSequenceNumber("6020");
         IPreparedCheckpointer secondPreparedCheckpoint = processingCheckpointer.prepareCheckpoint("6020", 0);
-        assertEquals(sn2, secondPreparedCheckpoint.getPendingCheckpoint());
-        assertEquals(sn2, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(sn2, secondPreparedCheckpoint.pendingCheckpoint());
+        assertEquals(sn2, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         // checkpoint in order
         firstPreparedCheckpoint.checkpoint();
         assertEquals(sn1, checkpoint.getCheckpoint(shardId));
-        assertEquals(sn1, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(sn1, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         secondPreparedCheckpoint.checkpoint();
         assertEquals(sn2, checkpoint.getCheckpoint(shardId));
-        assertEquals(sn2, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(sn2, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
     }
 
     /**
@@ -379,19 +376,19 @@ public class RecordProcessorCheckpointerTest {
 
         ExtendedSequenceNumber sn1 = new ExtendedSequenceNumber("7010");
         IPreparedCheckpointer firstPreparedCheckpoint = processingCheckpointer.prepareCheckpoint("7010", 0);
-        assertEquals(sn1, firstPreparedCheckpoint.getPendingCheckpoint());
-        assertEquals(sn1, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(sn1, firstPreparedCheckpoint.pendingCheckpoint());
+        assertEquals(sn1, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         ExtendedSequenceNumber sn2 = new ExtendedSequenceNumber("7020");
         IPreparedCheckpointer secondPreparedCheckpoint = processingCheckpointer.prepareCheckpoint("7020", 0);
-        assertEquals(sn2, secondPreparedCheckpoint.getPendingCheckpoint());
-        assertEquals(sn2, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(sn2, secondPreparedCheckpoint.pendingCheckpoint());
+        assertEquals(sn2, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         // checkpoint out of order
         secondPreparedCheckpoint.checkpoint();
         assertEquals(sn2, checkpoint.getCheckpoint(shardId));
-        assertEquals(sn2, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(sn2, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         try {
             firstPreparedCheckpoint.checkpoint();
@@ -549,23 +546,23 @@ public class RecordProcessorCheckpointerTest {
         IPreparedCheckpointer doesNothingPreparedCheckpoint =
                 processingCheckpointer.prepareCheckpoint(firstSequenceNumber.getSequenceNumber(), firstSequenceNumber.getSubSequenceNumber());
         assertTrue(doesNothingPreparedCheckpoint instanceof DoesNothingPreparedCheckpointer);
-        assertEquals(firstSequenceNumber, doesNothingPreparedCheckpoint.getPendingCheckpoint());
+        assertEquals(firstSequenceNumber, doesNothingPreparedCheckpoint.pendingCheckpoint());
         assertEquals(firstSequenceNumber, checkpoint.getCheckpoint(shardId));
-        assertEquals(firstSequenceNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(firstSequenceNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         // nothing happens after checkpointing a doesNothingPreparedCheckpoint
         doesNothingPreparedCheckpoint.checkpoint();
         assertEquals(firstSequenceNumber, checkpoint.getCheckpoint(shardId));
-        assertEquals(firstSequenceNumber, checkpoint.getCheckpointObject(shardId).getCheckpoint());
-        assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(firstSequenceNumber, checkpoint.getCheckpointObject(shardId).checkpoint());
+        assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         // advance to second
         processingCheckpointer.prepareCheckpoint(secondSequenceNumber.getSequenceNumber(), secondSequenceNumber.getSubSequenceNumber());
-        assertEquals(secondSequenceNumber, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(secondSequenceNumber, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
         processingCheckpointer.checkpoint(secondSequenceNumber.getSequenceNumber(), secondSequenceNumber.getSubSequenceNumber());
         assertEquals(secondSequenceNumber, checkpoint.getCheckpoint(shardId));
-        assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         ExtendedSequenceNumber[] valuesWeShouldNotBeAbleToCheckpointAt =
                 { tooSmall, // Shouldn't be able to move before the first value we ever checkpointed
@@ -596,13 +593,13 @@ public class RecordProcessorCheckpointerTest {
             assertEquals("Largest sequence number should not have changed",
                     thirdSequenceNumber,
                     processingCheckpointer.largestPermittedCheckpointValue());
-            assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+            assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
 
         }
 
         // advance to third number
         processingCheckpointer.prepareCheckpoint(thirdSequenceNumber.getSequenceNumber(), thirdSequenceNumber.getSubSequenceNumber());
-        assertEquals(thirdSequenceNumber, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+        assertEquals(thirdSequenceNumber, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
         processingCheckpointer.checkpoint(thirdSequenceNumber.getSequenceNumber(), thirdSequenceNumber.getSubSequenceNumber());
         assertEquals(thirdSequenceNumber, checkpoint.getCheckpoint(shardId));
 
@@ -614,7 +611,7 @@ public class RecordProcessorCheckpointerTest {
         assertEquals("Preparing a checkpoing at the sequence number at the end of a shard should be the same as "
                         + "preparing a checkpoint at SHARD_END",
                 ExtendedSequenceNumber.SHARD_END,
-                checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+                checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
     }
 
     private enum CheckpointAction {
@@ -788,8 +785,8 @@ public class RecordProcessorCheckpointerTest {
                     case PREPARE_THEN_CHECKPOINTER:
                         preparedCheckpoint = processingCheckpointer.prepareCheckpoint();
                         processingCheckpointer.checkpoint(
-                                preparedCheckpoint.getPendingCheckpoint().getSequenceNumber(),
-                                preparedCheckpoint.getPendingCheckpoint().getSubSequenceNumber());
+                                preparedCheckpoint.pendingCheckpoint().getSequenceNumber(),
+                                preparedCheckpoint.pendingCheckpoint().getSubSequenceNumber());
                 }
                 break;
             case WITH_SEQUENCE_NUMBER:
@@ -803,8 +800,8 @@ public class RecordProcessorCheckpointerTest {
                     case PREPARE_THEN_CHECKPOINTER:
                         preparedCheckpoint = processingCheckpointer.prepareCheckpoint(entry.getKey());
                         processingCheckpointer.checkpoint(
-                                preparedCheckpoint.getPendingCheckpoint().getSequenceNumber(),
-                                preparedCheckpoint.getPendingCheckpoint().getSubSequenceNumber());
+                                preparedCheckpoint.pendingCheckpoint().getSequenceNumber(),
+                                preparedCheckpoint.pendingCheckpoint().getSubSequenceNumber());
                 }
                 break;
             }
@@ -818,8 +815,8 @@ public class RecordProcessorCheckpointerTest {
 
             assertEquals(new ExtendedSequenceNumber(entry.getKey()), checkpoint.getCheckpoint(shardId));
             assertEquals(new ExtendedSequenceNumber(entry.getKey()),
-                    checkpoint.getCheckpointObject(shardId).getCheckpoint());
-            assertEquals(null, checkpoint.getCheckpointObject(shardId).getPendingCheckpoint());
+                    checkpoint.getCheckpointObject(shardId).checkpoint());
+            assertEquals(null, checkpoint.getCheckpointObject(shardId).pendingCheckpoint());
         }
     }
 

amazon-kinesis-client/src/test/java/software/amazon/kinesis/coordinator/KinesisClientLibConfigurationTest.java

@@ -20,26 +20,6 @@ import static org.junit.Assert.assertTrue;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.fail;
 
-import java.util.Date;
-
-import com.amazonaws.services.kinesis.clientlibrary.lib.worker.InitialPositionInStream;
-import org.junit.Test;
-import org.mockito.Mockito;
-
-import com.amazonaws.ClientConfiguration;
-import com.amazonaws.auth.AWSCredentialsProvider;
-import com.amazonaws.regions.Region;
-import com.amazonaws.regions.RegionUtils;
-import com.amazonaws.services.cloudwatch.AmazonCloudWatchClient;
-import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient;
-import com.amazonaws.services.kinesis.AmazonKinesisClient;
-import software.amazon.kinesis.coordinator.KinesisClientLibConfiguration;
-import software.amazon.kinesis.processor.IRecordProcessorFactory;
-import software.amazon.kinesis.metrics.MetricsLevel;
-import com.google.common.collect.ImmutableSet;
-
-import junit.framework.Assert;
-
 public class KinesisClientLibConfigurationTest {
     /*private static final long INVALID_LONG = 0L;
     private static final int INVALID_INT = 0;

amazon-kinesis-client/src/test/java/software/amazon/kinesis/coordinator/SchedulerTest.java

@@ -67,8 +67,8 @@ import software.amazon.kinesis.lifecycle.ShutdownInput;
 import software.amazon.kinesis.lifecycle.ShutdownReason;
 import software.amazon.kinesis.metrics.IMetricsFactory;
 import software.amazon.kinesis.metrics.MetricsConfig;
-import software.amazon.kinesis.processor.ICheckpoint;
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.Checkpointer;
+import software.amazon.kinesis.processor.RecordProcessor;
 import software.amazon.kinesis.processor.ProcessorConfig;
 import software.amazon.kinesis.processor.ProcessorFactory;
 import software.amazon.kinesis.retrieval.GetRecordsCache;
@@ -114,7 +114,7 @@ public class SchedulerTest {
     @Mock
     private LeaseManagerProxy leaseManagerProxy;
     @Mock
-    private ICheckpoint checkpoint;
+    private Checkpointer checkpoint;
 
     @Before
     public void setup() {
@@ -399,8 +399,8 @@ public class SchedulerTest {
 
     private static class TestRecordProcessorFactory implements ProcessorFactory {
         @Override
-        public IRecordProcessor createRecordProcessor() {
-            return new IRecordProcessor() {
+        public RecordProcessor createRecordProcessor() {
+            return new RecordProcessor() {
                 @Override
                 public void initialize(final InitializationInput initializationInput) {
                     // Do nothing.
@@ -458,7 +458,7 @@ public class SchedulerTest {
 
     private class TestKinesisCheckpointFactory implements CheckpointFactory {
         @Override
-        public ICheckpoint createCheckpoint(KinesisClientLibLeaseCoordinator leaseCoordinator) {
+        public Checkpointer createCheckpoint() {
             return checkpoint;
         }
     }

amazon-kinesis-client/src/test/java/software/amazon/kinesis/leases/DynamoDBLeaseTakerIntegrationTest.java

@@ -22,14 +22,14 @@ import org.junit.Test;
 
 import software.amazon.kinesis.leases.exceptions.LeasingException;
 
-public class LeaseTakerIntegrationTest extends LeaseIntegrationTest {
+public class DynamoDBLeaseTakerIntegrationTest extends LeaseIntegrationTest {
 
     private static final long LEASE_DURATION_MILLIS = 1000L;
-    private LeaseTaker<KinesisClientLease> taker;
+    private DynamoDBLeaseTaker<KinesisClientLease> taker;
 
     @Before
     public void setUp() {
-        taker = new LeaseTaker<KinesisClientLease>(leaseManager, "foo", LEASE_DURATION_MILLIS);
+        taker = new DynamoDBLeaseTaker<KinesisClientLease>(leaseManager, "foo", LEASE_DURATION_MILLIS);
     }
 
     @Test

amazon-kinesis-client/src/test/java/software/amazon/kinesis/leases/DynamoDBLeaseTakerTest.java

@@ -24,12 +24,11 @@ import org.junit.AfterClass;
 import org.junit.Before;
 import org.junit.BeforeClass;
 import org.junit.Test;
-import software.amazon.kinesis.leases.LeaseTaker;
 
 /**
  *
  */
-public class LeaseTakerTest {
+public class DynamoDBLeaseTakerTest {
 
     /**
      * @throws java.lang.Exception
@@ -60,17 +59,17 @@ public class LeaseTakerTest {
     }
 
     /**
-     * Test method for {@link LeaseTaker#stringJoin(java.util.Collection, java.lang.String)}.
+     * Test method for {@link DynamoDBLeaseTaker#stringJoin(java.util.Collection, java.lang.String)}.
      */
     @Test
     public final void testStringJoin() {
         List<String> strings = new ArrayList<>();
         
         strings.add("foo");
-        Assert.assertEquals("foo", LeaseTaker.stringJoin(strings, ", "));
+        Assert.assertEquals("foo", DynamoDBLeaseTaker.stringJoin(strings, ", "));
         
         strings.add("bar");
-        Assert.assertEquals("foo, bar", LeaseTaker.stringJoin(strings, ", "));        
+        Assert.assertEquals("foo, bar", DynamoDBLeaseTaker.stringJoin(strings, ", "));
     }
 
 }

amazon-kinesis-client/src/test/java/software/amazon/kinesis/leases/KinesisClientLibLeaseCoordinatorIntegrationTest.java

@@ -14,6 +14,11 @@
  */
 package software.amazon.kinesis.leases;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertTrue;
+
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
@@ -22,31 +27,38 @@ import java.util.Map;
 import java.util.UUID;
 import java.util.concurrent.Callable;
 
-import com.amazonaws.auth.DefaultAWSCredentialsProviderChain;
-import junit.framework.Assert;
-
 import org.junit.Before;
 import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.mockito.runners.MockitoJUnitRunner;
 
-
+import com.amazonaws.auth.DefaultAWSCredentialsProviderChain;
 import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient;
-import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
+
+import software.amazon.kinesis.checkpoint.DynamoDBCheckpointer;
 import software.amazon.kinesis.leases.exceptions.DependencyException;
 import software.amazon.kinesis.leases.exceptions.InvalidStateException;
 import software.amazon.kinesis.leases.exceptions.LeasingException;
 import software.amazon.kinesis.leases.exceptions.ProvisionedThroughputException;
+import software.amazon.kinesis.metrics.IMetricsFactory;
+import software.amazon.kinesis.metrics.NullMetricsFactory;
+import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
 
-import static org.hamcrest.CoreMatchers.notNullValue;
-import static org.hamcrest.MatcherAssert.assertThat;
-
+@RunWith(MockitoJUnitRunner.class)
 public class KinesisClientLibLeaseCoordinatorIntegrationTest {
-
-    private static KinesisClientLeaseManager leaseManager;
-    private KinesisClientLibLeaseCoordinator coordinator;
     private static final String TABLE_NAME = KinesisClientLibLeaseCoordinatorIntegrationTest.class.getSimpleName();
     private static final String WORKER_ID = UUID.randomUUID().toString();
-    private final String leaseKey = "shd-1";
+    private static final long LEASE_DURATION_MILLIS = 5000L;
+    private static final long EPSILON_MILLIS = 25L;
+    private static final int MAX_LEASES_FOR_WORKER = Integer.MAX_VALUE;
+    private static final int MAX_LEASES_TO_STEAL_AT_ONE_TIME = 1;
+    private static final int MAX_LEASE_RENEWER_THREAD_COUNT = 20;
+    private static KinesisClientLeaseManager leaseManager;
+    private static DynamoDBCheckpointer dynamoDBCheckpointer;
 
+    private KinesisClientLibLeaseCoordinator coordinator;
+    private final String leaseKey = "shd-1";
+    private final IMetricsFactory metricsFactory = new NullMetricsFactory();
 
     @Before
     public void setUp() throws ProvisionedThroughputException, DependencyException, InvalidStateException {
@@ -58,7 +70,11 @@ public class KinesisClientLibLeaseCoordinatorIntegrationTest {
         }
         leaseManager.createLeaseTableIfNotExists(10L, 10L);
         leaseManager.deleteAll();
-        coordinator = new KinesisClientLibLeaseCoordinator(leaseManager, WORKER_ID, 5000L, 50L);
+        coordinator = new KinesisClientLibLeaseCoordinator(leaseManager, WORKER_ID, LEASE_DURATION_MILLIS,
+                EPSILON_MILLIS, MAX_LEASES_FOR_WORKER, MAX_LEASES_TO_STEAL_AT_ONE_TIME, MAX_LEASE_RENEWER_THREAD_COUNT,
+                metricsFactory);
+        dynamoDBCheckpointer = new DynamoDBCheckpointer(coordinator, leaseManager, metricsFactory);
+
         coordinator.start();
     }
 
@@ -66,7 +82,7 @@ public class KinesisClientLibLeaseCoordinatorIntegrationTest {
      * Tests update checkpoint success.
      */
     @Test
-    public void testUpdateCheckpoint() throws LeasingException {
+    public void testUpdateCheckpoint() throws Exception {
         TestHarnessBuilder builder = new TestHarnessBuilder();
         builder.withLease(leaseKey, null).build();
 
@@ -82,17 +98,17 @@ public class KinesisClientLibLeaseCoordinatorIntegrationTest {
             }
         }
 
-        assertThat(lease, notNullValue());
+        assertNotNull(lease);
         ExtendedSequenceNumber newCheckpoint = new ExtendedSequenceNumber("newCheckpoint");
         // lease's leaseCounter is wrong at this point, but it shouldn't matter.
-        Assert.assertTrue(coordinator.setCheckpoint(lease.getLeaseKey(), newCheckpoint, lease.getConcurrencyToken()));
+        assertTrue(dynamoDBCheckpointer.setCheckpoint(lease.getLeaseKey(), newCheckpoint, lease.getConcurrencyToken()));
 
         Lease fromDynamo = leaseManager.getLease(lease.getLeaseKey());
 
         lease.setLeaseCounter(lease.getLeaseCounter() + 1);
         lease.setCheckpoint(newCheckpoint);
         lease.setLeaseOwner(coordinator.getWorkerIdentifier());
-        Assert.assertEquals(lease, fromDynamo);
+        assertEquals(lease, fromDynamo);
     }
 
     /**
@@ -107,18 +123,18 @@ public class KinesisClientLibLeaseCoordinatorIntegrationTest {
         coordinator.runLeaseRenewer();
         KinesisClientLease lease = coordinator.getCurrentlyHeldLease(leaseKey);
 
-        assertThat(lease, notNullValue());
+        assertNotNull(lease);
         leaseManager.renewLease(coordinator.getCurrentlyHeldLease(leaseKey));
 
         ExtendedSequenceNumber newCheckpoint = new ExtendedSequenceNumber("newCheckpoint");
-        Assert.assertFalse(coordinator.setCheckpoint(lease.getLeaseKey(), newCheckpoint, lease.getConcurrencyToken()));
+        assertFalse(dynamoDBCheckpointer.setCheckpoint(lease.getLeaseKey(), newCheckpoint, lease.getConcurrencyToken()));
 
         Lease fromDynamo = leaseManager.getLease(lease.getLeaseKey());
 
         lease.setLeaseCounter(lease.getLeaseCounter() + 1);
         // Counter and owner changed, but checkpoint did not.
         lease.setLeaseOwner(coordinator.getWorkerIdentifier());
-        Assert.assertEquals(lease, fromDynamo);
+        assertEquals(lease, fromDynamo);
     }
 
     /**
@@ -133,16 +149,16 @@ public class KinesisClientLibLeaseCoordinatorIntegrationTest {
         coordinator.runLeaseRenewer();
         KinesisClientLease lease = coordinator.getCurrentlyHeldLease(leaseKey);
 
-        assertThat(lease, notNullValue());
+        assertNotNull(lease);
 
         ExtendedSequenceNumber newCheckpoint = new ExtendedSequenceNumber("newCheckpoint");
-        Assert.assertFalse(coordinator.setCheckpoint(lease.getLeaseKey(), newCheckpoint, UUID.randomUUID()));
+        assertFalse(dynamoDBCheckpointer.setCheckpoint(lease.getLeaseKey(), newCheckpoint, UUID.randomUUID()));
 
         Lease fromDynamo = leaseManager.getLease(lease.getLeaseKey());
 
         // Owner should be the only thing that changed.
         lease.setLeaseOwner(coordinator.getWorkerIdentifier());
-        Assert.assertEquals(lease, fromDynamo);
+        assertEquals(lease, fromDynamo);
     }
 
     public static class TestHarnessBuilder {
@@ -201,7 +217,7 @@ public class KinesisClientLibLeaseCoordinatorIntegrationTest {
             }
             original.setLeaseOwner(newWorkerIdentifier);
 
-            Assert.assertEquals(original, actual); // Assert the contents of the lease
+            assertEquals(original, actual); // Assert the contents of the lease
         }
 
         public void addLeasesToRenew(ILeaseRenewer<KinesisClientLease> renewer, String... shardIds)
@@ -210,7 +226,7 @@ public class KinesisClientLibLeaseCoordinatorIntegrationTest {
 
             for (String shardId : shardIds) {
                 KinesisClientLease lease = leases.get(shardId);
-                Assert.assertNotNull(lease);
+                assertNotNull(lease);
                 leasesToRenew.add(lease);
             }
 
@@ -222,17 +238,17 @@ public class KinesisClientLibLeaseCoordinatorIntegrationTest {
             renewer.renewLeases();
 
             Map<String, KinesisClientLease> heldLeases = renewer.getCurrentlyHeldLeases();
-            Assert.assertEquals(renewedShardIds.length, heldLeases.size());
+            assertEquals(renewedShardIds.length, heldLeases.size());
 
             for (String shardId : renewedShardIds) {
                 KinesisClientLease original = leases.get(shardId);
-                Assert.assertNotNull(original);
+                assertNotNull(original);
 
                 KinesisClientLease actual = heldLeases.get(shardId);
-                Assert.assertNotNull(actual);
+                assertNotNull(actual);
 
                 original.setLeaseCounter(original.getLeaseCounter() + 1);
-                Assert.assertEquals(original, actual);
+                assertEquals(original, actual);
             }
 
             return heldLeases;

amazon-kinesis-client/src/test/java/software/amazon/kinesis/leases/KinesisClientLibLeaseCoordinatorTest.java

@@ -14,27 +14,28 @@
  */
 package software.amazon.kinesis.leases;
 
-import static org.mockito.Matchers.anyLong;
-import static org.mockito.Mockito.doReturn;
+import static org.mockito.Matchers.eq;
+import static org.mockito.Mockito.verify;
+import static org.mockito.Mockito.when;
 
 import java.util.UUID;
 
-import junit.framework.Assert;
-
 import org.junit.Before;
 import org.junit.Test;
+import org.junit.runner.RunWith;
 import org.mockito.Mock;
-import org.mockito.MockitoAnnotations;
 
 import com.amazonaws.services.kinesis.clientlibrary.exceptions.KinesisClientLibException;
 import com.amazonaws.services.kinesis.clientlibrary.exceptions.ShutdownException;
-import software.amazon.kinesis.leases.KinesisClientLibLeaseCoordinator;
+import org.mockito.runners.MockitoJUnitRunner;
+import software.amazon.kinesis.checkpoint.DynamoDBCheckpointer;
+import software.amazon.kinesis.metrics.IMetricsFactory;
 import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
 import software.amazon.kinesis.leases.exceptions.DependencyException;
 import software.amazon.kinesis.leases.exceptions.InvalidStateException;
 import software.amazon.kinesis.leases.exceptions.ProvisionedThroughputException;
-import software.amazon.kinesis.leases.ILeaseManager;
 
+@RunWith(MockitoJUnitRunner.class)
 public class KinesisClientLibLeaseCoordinatorTest {
     private static final String SHARD_ID = "shardId-test";
     private static final String WORK_ID = "workId-test";
@@ -42,35 +43,38 @@ public class KinesisClientLibLeaseCoordinatorTest {
     private static final ExtendedSequenceNumber TEST_CHKPT = new ExtendedSequenceNumber("string-test");
     private static final UUID TEST_UUID = UUID.randomUUID();
 
-    @SuppressWarnings("rawtypes")
     @Mock
-    private ILeaseManager mockLeaseManager;
+    private ILeaseManager<KinesisClientLease> leaseManager;
+    @Mock
+    private LeaseCoordinator<KinesisClientLease> leaseCoordinator;
+    @Mock
+    private IMetricsFactory metricsFactory;
 
-    private KinesisClientLibLeaseCoordinator leaseCoordinator;
+    private DynamoDBCheckpointer dynamoDBCheckpointer;
 
     @SuppressWarnings("unchecked")
     @Before
     public void setUpLeaseCoordinator() throws ProvisionedThroughputException, DependencyException {
-        // Initialize the annotation
-        MockitoAnnotations.initMocks(this);
-        // Set up lease coordinator
-        doReturn(true).when(mockLeaseManager).createLeaseTableIfNotExists(anyLong(), anyLong());
-        leaseCoordinator = new KinesisClientLibLeaseCoordinator(mockLeaseManager, WORK_ID, TEST_LONG, TEST_LONG);
+        dynamoDBCheckpointer = new DynamoDBCheckpointer(leaseCoordinator, leaseManager, metricsFactory);
     }
 
     @Test(expected = ShutdownException.class)
-    public void testSetCheckpointWithUnownedShardId()
-        throws KinesisClientLibException, DependencyException, InvalidStateException, ProvisionedThroughputException {
-        final boolean succeess = leaseCoordinator.setCheckpoint(SHARD_ID, TEST_CHKPT, TEST_UUID);
-        Assert.assertFalse("Set Checkpoint should return failure", succeess);
-        leaseCoordinator.setCheckpoint(SHARD_ID, TEST_CHKPT, TEST_UUID.toString());
+    public void testSetCheckpointWithUnownedShardId() throws KinesisClientLibException, DependencyException, InvalidStateException, ProvisionedThroughputException {
+        final KinesisClientLease lease = new KinesisClientLease();
+        when(leaseManager.getLease(eq(SHARD_ID))).thenReturn(lease);
+        when(leaseCoordinator.updateLease(eq(lease), eq(TEST_UUID))).thenReturn(false);
+
+        dynamoDBCheckpointer.setCheckpoint(SHARD_ID, TEST_CHKPT, TEST_UUID.toString());
+
+        verify(leaseManager).getLease(eq(SHARD_ID));
+        verify(leaseCoordinator).updateLease(eq(lease), eq(TEST_UUID));
     }
 
-    @Test(expected = DependencyException.class)
-    public void testWaitLeaseTableTimeout()
-        throws DependencyException, ProvisionedThroughputException, IllegalStateException {
-        // Set mock lease manager to return false in waiting
-        doReturn(false).when(mockLeaseManager).waitUntilLeaseTableExists(anyLong(), anyLong());
-        leaseCoordinator.initialize();
-    }
+//    @Test(expected = DependencyException.class)
+//    public void testWaitLeaseTableTimeout()
+//        throws DependencyException, ProvisionedThroughputException, IllegalStateException {
+//         Set mock lease manager to return false in waiting
+//        doReturn(false).when(leaseManager).waitUntilLeaseTableExists(anyLong(), anyLong());
+//        leaseCoordinator.initialize();
+//    }
 }

amazon-kinesis-client/src/test/java/software/amazon/kinesis/leases/TestHarnessBuilder.java

@@ -91,7 +91,7 @@ public class TestHarnessBuilder {
         currentTimeNanos += millis * 1000000;
     }
 
-    public Map<String, KinesisClientLease> takeMutateAssert(LeaseTaker<KinesisClientLease> taker, int numToTake)
+    public Map<String, KinesisClientLease> takeMutateAssert(DynamoDBLeaseTaker<KinesisClientLease> taker, int numToTake)
         throws LeasingException {
         Map<String, KinesisClientLease> result = taker.takeLeases(timeProvider);
         Assert.assertEquals(numToTake, result.size());
@@ -106,7 +106,7 @@ public class TestHarnessBuilder {
         return result;
     }
 
-    public Map<String, KinesisClientLease> takeMutateAssert(LeaseTaker<KinesisClientLease> taker, String... takenShardIds)
+    public Map<String, KinesisClientLease> takeMutateAssert(DynamoDBLeaseTaker<KinesisClientLease> taker, String... takenShardIds)
         throws LeasingException {
         Map<String, KinesisClientLease> result = taker.takeLeases(timeProvider);
         Assert.assertEquals(takenShardIds.length, result.size());

amazon-kinesis-client/src/test/java/software/amazon/kinesis/lifecycle/ConsumerStatesTest.java

@@ -44,14 +44,14 @@ import com.amazonaws.services.kinesis.AmazonKinesis;
 import com.amazonaws.services.kinesis.clientlibrary.lib.worker.InitialPositionInStream;
 import com.amazonaws.services.kinesis.clientlibrary.lib.worker.InitialPositionInStreamExtended;
 
-import software.amazon.kinesis.coordinator.RecordProcessorCheckpointer;
+import software.amazon.kinesis.checkpoint.RecordProcessorCheckpointer;
 import software.amazon.kinesis.leases.ILeaseManager;
 import software.amazon.kinesis.leases.KinesisClientLease;
 import software.amazon.kinesis.leases.LeaseManagerProxy;
 import software.amazon.kinesis.leases.ShardInfo;
 import software.amazon.kinesis.metrics.IMetricsFactory;
-import software.amazon.kinesis.processor.ICheckpoint;
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.Checkpointer;
+import software.amazon.kinesis.processor.RecordProcessor;
 import software.amazon.kinesis.processor.IRecordProcessorCheckpointer;
 import software.amazon.kinesis.retrieval.GetRecordsCache;
 
@@ -64,7 +64,7 @@ public class ConsumerStatesTest {
     private ShardConsumer consumer;
 
     @Mock
-    private IRecordProcessor recordProcessor;
+    private RecordProcessor recordProcessor;
     @Mock
     private RecordProcessorCheckpointer recordProcessorCheckpointer;
     @Mock
@@ -74,7 +74,7 @@ public class ConsumerStatesTest {
     @Mock
     private ILeaseManager<KinesisClientLease> leaseManager;
     @Mock
-    private ICheckpoint checkpoint;
+    private Checkpointer checkpoint;
     @Mock
     private ShutdownNotification shutdownNotification;
     @Mock
@@ -144,8 +144,8 @@ public class ConsumerStatesTest {
         ITask task = state.createTask(consumer);
 
         assertThat(task, initTask(ShardInfo.class, "shardInfo", equalTo(shardInfo)));
-        assertThat(task, initTask(IRecordProcessor.class, "recordProcessor", equalTo(recordProcessor)));
-        assertThat(task, initTask(ICheckpoint.class, "checkpoint", equalTo(checkpoint)));
+        assertThat(task, initTask(RecordProcessor.class, "recordProcessor", equalTo(recordProcessor)));
+        assertThat(task, initTask(Checkpointer.class, "checkpoint", equalTo(checkpoint)));
         assertThat(task, initTask(RecordProcessorCheckpointer.class, "recordProcessorCheckpointer",
                 equalTo(recordProcessorCheckpointer)));
         assertThat(task, initTask(Long.class, "backoffTimeMillis", equalTo(taskBackoffTimeMillis)));
@@ -171,7 +171,7 @@ public class ConsumerStatesTest {
         ITask task = state.createTask(consumer);
 
         assertThat(task, procTask(ShardInfo.class, "shardInfo", equalTo(shardInfo)));
-        assertThat(task, procTask(IRecordProcessor.class, "recordProcessor", equalTo(recordProcessor)));
+        assertThat(task, procTask(RecordProcessor.class, "recordProcessor", equalTo(recordProcessor)));
         assertThat(task, procTask(RecordProcessorCheckpointer.class, "recordProcessorCheckpointer",
                 equalTo(recordProcessorCheckpointer)));
         assertThat(task, procTask(Long.class, "backoffTimeMillis", equalTo(taskBackoffTimeMillis)));
@@ -198,7 +198,7 @@ public class ConsumerStatesTest {
         ITask task = state.createTask(consumer);
 
         assertThat(task, procTask(ShardInfo.class, "shardInfo", equalTo(shardInfo)));
-        assertThat(task, procTask(IRecordProcessor.class, "recordProcessor", equalTo(recordProcessor)));
+        assertThat(task, procTask(RecordProcessor.class, "recordProcessor", equalTo(recordProcessor)));
         assertThat(task, procTask(RecordProcessorCheckpointer.class, "recordProcessorCheckpointer",
                 equalTo(recordProcessorCheckpointer)));
         assertThat(task, procTask(Long.class, "backoffTimeMillis", equalTo(taskBackoffTimeMillis)));
@@ -225,7 +225,7 @@ public class ConsumerStatesTest {
         ITask task = state.createTask(consumer);
 
         assertThat(task, procTask(ShardInfo.class, "shardInfo", equalTo(shardInfo)));
-        assertThat(task, procTask(IRecordProcessor.class, "recordProcessor", equalTo(recordProcessor)));
+        assertThat(task, procTask(RecordProcessor.class, "recordProcessor", equalTo(recordProcessor)));
         assertThat(task, procTask(RecordProcessorCheckpointer.class, "recordProcessorCheckpointer",
                 equalTo(recordProcessorCheckpointer)));
         assertThat(task, procTask(Long.class, "backoffTimeMillis", equalTo(taskBackoffTimeMillis)));
@@ -250,7 +250,7 @@ public class ConsumerStatesTest {
         consumer.notifyShutdownRequested(shutdownNotification);
         ITask task = state.createTask(consumer);
 
-        assertThat(task, shutdownReqTask(IRecordProcessor.class, "recordProcessor", equalTo(recordProcessor)));
+        assertThat(task, shutdownReqTask(RecordProcessor.class, "recordProcessor", equalTo(recordProcessor)));
         assertThat(task, shutdownReqTask(IRecordProcessorCheckpointer.class, "recordProcessorCheckpointer",
                 equalTo(recordProcessorCheckpointer)));
         assertThat(task, shutdownReqTask(ShutdownNotification.class, "shutdownNotification", equalTo(shutdownNotification)));
@@ -296,7 +296,7 @@ public class ConsumerStatesTest {
         ITask task = state.createTask(consumer);
 
         assertThat(task, shutdownTask(ShardInfo.class, "shardInfo", equalTo(shardInfo)));
-        assertThat(task, shutdownTask(IRecordProcessor.class, "recordProcessor", equalTo(recordProcessor)));
+        assertThat(task, shutdownTask(RecordProcessor.class, "recordProcessor", equalTo(recordProcessor)));
         assertThat(task, shutdownTask(RecordProcessorCheckpointer.class, "recordProcessorCheckpointer",
                 equalTo(recordProcessorCheckpointer)));
         assertThat(task, shutdownTask(ShutdownReason.class, "reason", equalTo(reason)));

amazon-kinesis-client/src/test/java/software/amazon/kinesis/lifecycle/ProcessTaskTest.java

@@ -46,10 +46,10 @@ import com.amazonaws.services.kinesis.model.Record;
 import com.google.protobuf.ByteString;
 
 import lombok.Data;
-import software.amazon.kinesis.coordinator.RecordProcessorCheckpointer;
+import software.amazon.kinesis.checkpoint.RecordProcessorCheckpointer;
 import software.amazon.kinesis.leases.LeaseManagerProxy;
 import software.amazon.kinesis.leases.ShardInfo;
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.RecordProcessor;
 import software.amazon.kinesis.retrieval.ThrottlingReporter;
 import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
 import software.amazon.kinesis.retrieval.kpl.Messages;
@@ -79,7 +79,7 @@ public class ProcessTaskTest {
     private final long taskBackoffTimeMillis = 1L;
 
     @Mock
-    private IRecordProcessor recordProcessor;
+    private RecordProcessor recordProcessor;
     @Mock
     private RecordProcessorCheckpointer checkpointer;
     @Mock

amazon-kinesis-client/src/test/java/software/amazon/kinesis/lifecycle/ShardConsumerTest.java

@@ -62,7 +62,7 @@ import org.mockito.Mock;
 import org.mockito.runners.MockitoJUnitRunner;
 
 import com.amazonaws.services.kinesis.AmazonKinesis;
-import com.amazonaws.services.kinesis.clientlibrary.lib.checkpoint.InMemoryCheckpointImpl;
+import com.amazonaws.services.kinesis.clientlibrary.lib.checkpoint.InMemoryCheckpointer;
 import com.amazonaws.services.kinesis.clientlibrary.lib.worker.InitialPositionInStream;
 import com.amazonaws.services.kinesis.clientlibrary.lib.worker.InitialPositionInStreamExtended;
 import com.amazonaws.services.kinesis.clientlibrary.proxies.KinesisLocalFileProxy;
@@ -74,15 +74,15 @@ import com.amazonaws.services.kinesis.model.ShardIteratorType;
 import lombok.extern.slf4j.Slf4j;
 import software.amazon.kinesis.checkpoint.Checkpoint;
 import software.amazon.kinesis.coordinator.KinesisClientLibConfiguration;
-import software.amazon.kinesis.coordinator.RecordProcessorCheckpointer;
+import software.amazon.kinesis.checkpoint.RecordProcessorCheckpointer;
 import software.amazon.kinesis.leases.ILeaseManager;
 import software.amazon.kinesis.leases.KinesisClientLease;
 import software.amazon.kinesis.leases.LeaseManagerProxy;
 import software.amazon.kinesis.leases.ShardInfo;
 import software.amazon.kinesis.metrics.IMetricsFactory;
 import software.amazon.kinesis.metrics.NullMetricsFactory;
-import software.amazon.kinesis.processor.ICheckpoint;
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.Checkpointer;
+import software.amazon.kinesis.processor.RecordProcessor;
 import software.amazon.kinesis.retrieval.AsynchronousGetRecordsRetrievalStrategy;
 import software.amazon.kinesis.retrieval.BlockingGetRecordsCache;
 import software.amazon.kinesis.retrieval.GetRecordsCache;
@@ -135,13 +135,13 @@ public class ShardConsumerTest {
     @Mock
     private RecordsFetcherFactory recordsFetcherFactory;
     @Mock
-    private IRecordProcessor recordProcessor;
+    private RecordProcessor recordProcessor;
     @Mock
     private KinesisClientLibConfiguration config;
     @Mock
     private ILeaseManager<KinesisClientLease> leaseManager;
     @Mock
-    private ICheckpoint checkpoint;
+    private Checkpointer checkpoint;
     @Mock
     private ShutdownNotification shutdownNotification;
     @Mock
@@ -287,7 +287,7 @@ public class ShardConsumerTest {
         IKinesisProxy fileBasedProxy = new KinesisLocalFileProxy(file.getAbsolutePath());
 
         final int maxRecords = 2;
-        ICheckpoint checkpoint = new InMemoryCheckpointImpl(startSeqNum.toString());
+        Checkpointer checkpoint = new InMemoryCheckpointer(startSeqNum.toString());
         checkpoint.setCheckpoint(shardId, ExtendedSequenceNumber.TRIM_HORIZON, concurrencyToken);
         when(leaseManager.getLease(anyString())).thenReturn(null);
         TestStreamlet processor = new TestStreamlet();
@@ -390,7 +390,7 @@ public class ShardConsumerTest {
         IKinesisProxy fileBasedProxy = new KinesisLocalFileProxy(file.getAbsolutePath());
 
         final int maxRecords = 2;
-        ICheckpoint checkpoint = new InMemoryCheckpointImpl(startSeqNum.toString());
+        Checkpointer checkpoint = new InMemoryCheckpointer(startSeqNum.toString());
         checkpoint.setCheckpoint(shardId, ExtendedSequenceNumber.TRIM_HORIZON, concurrencyToken);
         when(leaseManager.getLease(anyString())).thenReturn(null);
 
@@ -485,7 +485,7 @@ public class ShardConsumerTest {
         IKinesisProxy fileBasedProxy = new KinesisLocalFileProxy(file.getAbsolutePath());
 
         final int maxRecords = 2;
-        ICheckpoint checkpoint = new InMemoryCheckpointImpl(startSeqNum.toString());
+        Checkpointer checkpoint = new InMemoryCheckpointer(startSeqNum.toString());
         checkpoint.setCheckpoint(streamShardId, ExtendedSequenceNumber.AT_TIMESTAMP, testConcurrencyToken);
         when(leaseManager.getLease(anyString())).thenReturn(null);
         TestStreamlet processor = new TestStreamlet();

amazon-kinesis-client/src/test/java/software/amazon/kinesis/lifecycle/ShutdownTaskTest.java

@@ -33,12 +33,12 @@ import com.amazonaws.services.kinesis.clientlibrary.exceptions.internal.KinesisC
 import com.amazonaws.services.kinesis.clientlibrary.lib.worker.InitialPositionInStream;
 import com.amazonaws.services.kinesis.clientlibrary.lib.worker.InitialPositionInStreamExtended;
 
-import software.amazon.kinesis.coordinator.RecordProcessorCheckpointer;
+import software.amazon.kinesis.checkpoint.RecordProcessorCheckpointer;
 import software.amazon.kinesis.leases.ILeaseManager;
 import software.amazon.kinesis.leases.KinesisClientLease;
 import software.amazon.kinesis.leases.LeaseManagerProxy;
 import software.amazon.kinesis.leases.ShardInfo;
-import software.amazon.kinesis.processor.IRecordProcessor;
+import software.amazon.kinesis.processor.RecordProcessor;
 import software.amazon.kinesis.retrieval.GetRecordsCache;
 import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
 import software.amazon.kinesis.utils.TestStreamlet;
@@ -57,7 +57,7 @@ public class ShutdownTaskTest {
     private final String shardId = "shardId-0000397840";
     private boolean cleanupLeasesOfCompletedShards = false;
     private boolean ignoreUnexpectedChildShards = false;
-    private IRecordProcessor recordProcessor;
+    private RecordProcessor recordProcessor;
     private ShardInfo shardInfo;
     private ShutdownTask task;
     

amazon-kinesis-client/src/test/java/software/amazon/kinesis/retrieval/KinesisDataFetcherTest.java

@@ -56,7 +56,7 @@ import com.amazonaws.services.kinesis.model.ResourceNotFoundException;
 import com.amazonaws.services.kinesis.model.ShardIteratorType;
 
 import software.amazon.kinesis.checkpoint.SentinelCheckpoint;
-import software.amazon.kinesis.processor.ICheckpoint;
+import software.amazon.kinesis.processor.Checkpointer;
 import software.amazon.kinesis.retrieval.kpl.ExtendedSequenceNumber;
 
 /**
@@ -134,7 +134,7 @@ public class KinesisDataFetcherTest {
 
     @Test
     public void testadvanceIteratorTo() throws KinesisClientLibException {
-        final ICheckpoint checkpoint = mock(ICheckpoint.class);
+        final Checkpointer checkpoint = mock(Checkpointer.class);
         final String iteratorA = "foo";
         final String iteratorB = "bar";
         final String seqA = "123";
@@ -398,7 +398,7 @@ public class KinesisDataFetcherTest {
         when(amazonKinesis.getRecords(recordsCaptor.capture()))
                 .thenReturn(new GetRecordsResult().withRecords(expectedRecords));
 
-        ICheckpoint checkpoint = mock(ICheckpoint.class);
+        Checkpointer checkpoint = mock(Checkpointer.class);
         when(checkpoint.getCheckpoint(SHARD_ID)).thenReturn(new ExtendedSequenceNumber(seqNo));
 
         final GetRecordsRetrievalStrategy getRecordsRetrievalStrategy =

amazon-kinesis-client/src/test/java/software/amazon/kinesis/utils/TestStreamlet.java

@@ -29,8 +29,8 @@ import com.amazonaws.services.kinesis.clientlibrary.exceptions.ThrottlingExcepti
 import software.amazon.kinesis.leases.ShardSequenceVerifier;
 import software.amazon.kinesis.lifecycle.ShutdownReason;
 import software.amazon.kinesis.processor.IRecordProcessorCheckpointer;
-import software.amazon.kinesis.processor.IRecordProcessor;
-import software.amazon.kinesis.processor.IShutdownNotificationAware;
+import software.amazon.kinesis.processor.RecordProcessor;
+import software.amazon.kinesis.processor.ShutdownNotificationAware;
 import software.amazon.kinesis.lifecycle.InitializationInput;
 import software.amazon.kinesis.lifecycle.ProcessRecordsInput;
 import software.amazon.kinesis.lifecycle.ShutdownInput;
@@ -42,7 +42,7 @@ import lombok.extern.slf4j.Slf4j;
  * Streamlet that tracks records it's seen - useful for testing.
  */
 @Slf4j
-public class TestStreamlet implements IRecordProcessor, IShutdownNotificationAware {
+public class TestStreamlet implements RecordProcessor, ShutdownNotificationAware {
     private List<Record> records = new ArrayList<Record>();
 
     private Set<String> processedSeqNums = new HashSet<String>(); // used for deduping

amazon-kinesis-client/src/test/java/software/amazon/kinesis/utils/TestStreamletFactory.java

@@ -19,13 +19,13 @@ import java.util.List;
 import java.util.concurrent.Semaphore;
 
 import software.amazon.kinesis.leases.ShardSequenceVerifier;
-import software.amazon.kinesis.processor.IRecordProcessor;
-import software.amazon.kinesis.processor.IRecordProcessorFactory;
+import software.amazon.kinesis.processor.RecordProcessor;
+import software.amazon.kinesis.processor.RecordProcessorFactory;
 
 /**
  * Factory for TestStreamlet record processors.
  */
-public class TestStreamletFactory implements IRecordProcessorFactory {
+public class TestStreamletFactory implements RecordProcessorFactory {
 
     // Will be passed to the TestStreamlet. Can be used to check if all records have been processed.
     private Semaphore semaphore;
@@ -41,7 +41,7 @@ public class TestStreamletFactory implements IRecordProcessorFactory {
     }
 
     @Override
-    public synchronized IRecordProcessor createProcessor() {
+    public synchronized RecordProcessor createProcessor() {
         TestStreamlet processor = new TestStreamlet(semaphore, shardSequenceVerifier);
         testStreamlets.add(processor);
         return processor;