reitit/modules/reitit-core/java-src/reitit/SegmentTrie.java
2019-01-14 10:45:27 +02:00

334 lines
9.3 KiB
Java

package reitit;
import clojure.lang.Keyword;
import java.io.UnsupportedEncodingException;
import java.net.URLEncoder;
import java.util.*;
public class SegmentTrie {
public static ArrayList<String> split(final String path) {
final ArrayList<String> segments = new ArrayList<>(4);
final int size = path.length();
int start = 1;
for (int i = start; i < size; i++) {
final char c = path.charAt(i);
if (c == '/') {
segments.add(path.substring(start, i));
start = i + 1;
}
}
segments.add(path.substring(start, size));
return segments;
}
static String encode(String s) {
try {
if (s.contains("%")) {
String _s = s;
if (s.contains("+")) {
_s = s.replace("+", "%2B");
}
return URLEncoder.encode(_s, "UTF-8");
}
} catch (UnsupportedEncodingException ignored) {
}
return s;
}
public static class Match {
public final Map<Keyword, String> params = new HashMap<>();
public Object data;
@Override
public String toString() {
Map<Object, Object> m = new HashMap<>();
m.put(Keyword.intern("data"), data);
m.put(Keyword.intern("params"), params);
return m.toString();
}
}
private Map<String, SegmentTrie> childs = new HashMap<>();
private Map<Keyword, SegmentTrie> wilds = new HashMap<>();
private Map<Keyword, SegmentTrie> catchAll = new HashMap<>();
private Object data;
public SegmentTrie add(String path, Object data) {
List<String> paths = split(path);
SegmentTrie pointer = this;
for (String p : paths) {
if (p.startsWith(":")) {
Keyword k = Keyword.intern(p.substring(1));
SegmentTrie s = pointer.wilds.get(k);
if (s == null) {
s = new SegmentTrie();
pointer.wilds.put(k, s);
}
pointer = s;
} else if (p.startsWith("*")) {
Keyword k = Keyword.intern(p.substring(1));
SegmentTrie s = pointer.catchAll.get(k);
if (s == null) {
s = new SegmentTrie();
pointer.catchAll.put(k, s);
}
break;
} else {
SegmentTrie s = pointer.childs.get(p);
if (s == null) {
s = new SegmentTrie();
pointer.childs.put(p, s);
}
pointer = s;
}
}
pointer.data = data;
return this;
}
private Matcher staticMatcher() {
if (childs.size() == 1) {
return new StaticMatcher(childs.keySet().iterator().next(), childs.values().iterator().next().matcher());
} else {
Map<String, Matcher> m = new HashMap<>();
for (Map.Entry<String, SegmentTrie> e : childs.entrySet()) {
m.put(e.getKey(), e.getValue().matcher());
}
return new StaticMapMatcher(m);
}
}
public Matcher matcher() {
Matcher m;
if (!catchAll.isEmpty()) {
m = new CatchAllMatcher(catchAll.keySet().iterator().next(), catchAll.values().iterator().next().data);
} else if (!wilds.isEmpty()) {
List<Matcher> matchers = new ArrayList<>();
if (data != null) {
matchers.add(new DataMatcher(data));
}
if (!childs.isEmpty()) {
matchers.add(staticMatcher());
}
for (Map.Entry<Keyword, SegmentTrie> e : wilds.entrySet()) {
matchers.add(new WildMatcher(e.getKey(), e.getValue().matcher()));
}
m = new LinearMatcher(matchers);
} else if (!childs.isEmpty()) {
m = staticMatcher();
} else {
return new DataMatcher(data);
}
if (data != null) {
m = new LinearMatcher(Arrays.asList(new DataMatcher(data), m));
}
return m;
}
public interface Matcher {
Match match(int i, List<String> segments, Match match);
}
public static final class StaticMatcher implements Matcher {
private final String segment;
private final Matcher child;
StaticMatcher(String segment, Matcher child) {
this.segment = segment;
this.child = child;
}
@Override
public Match match(int i, List<String> segments, Match match) {
if (i < segments.size() && segment.equals(segments.get(i))) {
return child.match(i + 1, segments, match);
}
return null;
}
@Override
public String toString() {
return "[\"" + segment + "\" " + child + "]";
}
}
public static final class WildMatcher implements Matcher {
private final Keyword parameter;
private final Matcher child;
WildMatcher(Keyword parameter, Matcher child) {
this.parameter = parameter;
this.child = child;
}
@Override
public Match match(int i, List<String> segments, Match match) {
final Match m = child.match(i + 1, segments, match);
if (m != null) {
m.params.put(parameter, encode(segments.get(i)));
return m;
}
return null;
}
@Override
public String toString() {
return "[" + parameter + " " + child + "]";
}
}
public static final class CatchAllMatcher implements Matcher {
private final Keyword parameter;
private final Object data;
CatchAllMatcher(Keyword parameter, Object data) {
this.parameter = parameter;
this.data = data;
}
@Override
public Match match(int i, List<String> segments, Match match) {
match.params.put(parameter, encode(String.join("/", segments.subList(i, segments.size()))));
match.data = data;
return match;
}
@Override
public String toString() {
return "[" + parameter + " " + new DataMatcher(data) + "]";
}
}
public static final class StaticMapMatcher implements Matcher {
private final Map<String, Matcher> map;
StaticMapMatcher(Map<String, Matcher> map) {
this.map = map;
}
@Override
public Match match(int i, List<String> segments, Match match) {
final Matcher child = map.get(segments.get(i));
if (child != null) {
return child.match(i + 1, segments, match);
}
return null;
}
@Override
public String toString() {
StringBuilder b = new StringBuilder();
b.append("{");
List<String> keys = new ArrayList<>(map.keySet());
for (int i = 0; i < keys.size(); i++) {
String path = keys.get(i);
Matcher value = map.get(path);
b.append("\"").append(path).append("\" ").append(value);
if (i < keys.size() - 1) {
b.append(", ");
}
}
b.append("}");
return b.toString();
}
}
public static final class LinearMatcher implements Matcher {
private final List<Matcher> childs;
LinearMatcher(List<Matcher> childs) {
this.childs = childs;
}
@Override
public Match match(int i, List<String> segments, Match match) {
for (Matcher child : childs) {
final Match m = child.match(i, segments, match);
if (m != null) {
return m;
}
}
return null;
}
@Override
public String toString() {
return childs.toString();
}
}
public static final class DataMatcher implements Matcher {
private final Object data;
DataMatcher(Object data) {
this.data = data;
}
@Override
public Match match(int i, List<String> segments, Match match) {
if (i == segments.size()) {
match.data = data;
return match;
}
return null;
}
@Override
public String toString() {
return (data != null ? data.toString() : "null");
}
}
public static Match lookup(Matcher matcher, String path) {
return matcher.match(0, split(path), new Match());
}
public static Matcher sample() {
Map<String, Matcher> m1 = new HashMap<>();
m1.put("profile", new WildMatcher(Keyword.intern("type"), new DataMatcher(1)));
m1.put("permissions", new DataMatcher(2));
Map<String, Matcher> m2 = new HashMap<>();
m2.put("user", new WildMatcher(Keyword.intern("id"), new StaticMapMatcher(m1)));
m2.put("company", new WildMatcher(Keyword.intern("cid"), new StaticMatcher("dept", new WildMatcher(Keyword.intern("did"), new DataMatcher(3)))));
m2.put("public", new CatchAllMatcher(Keyword.intern("*"), 4));
m2.put("kikka", new LinearMatcher(Arrays.asList(new StaticMatcher("ping", new DataMatcher(5)), new WildMatcher(Keyword.intern("id"), new StaticMatcher("ping", new DataMatcher(6))))));
return new StaticMapMatcher(m2);
}
public static void main(String[] args) {
SegmentTrie trie = new SegmentTrie();
//trie.add("/kikka/:id/permissions", 1);
trie.add("/kikka/:id", 2);
trie.add("/kakka/ping", 3);
Matcher m = trie.matcher();
System.err.println(m);
System.out.println(lookup(m, "/kikka/1/permissions"));
System.out.println(lookup(m, "/kikka/1"));
/*
SegmentTrie trie = new SegmentTrie();
trie.add("/user/:id/profile/:type", 1);
trie.add("/user/:id/permissions", 2);
trie.add("/company/:cid/dept/:did", 3);
trie.add("/this/is/a/static/route", 4);
Matcher m = trie.matcher();
System.out.println(m);
System.err.println(lookup(m, "/this/is/a/static/route"));
System.err.println(lookup(m, "/user/1234/profile/compact"));
System.err.println(lookup(m, "/company/1234/dept/5678"));
System.err.println();
*/
/*
System.err.println(lookup(sample(), "/user/1234/profile/compact"));
System.err.println(lookup(sample(), "/public/images/logo.jpg"));
System.err.println(lookup(sample(), "/kikka/ping"));
System.err.println(lookup(sample(), "/kikka/kukka/ping"));
*/
}
}