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Gradle 6.9.1 API redistribution.
/*
* Copyright 2016 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License 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 org.gradle.internal.util;
import org.gradle.api.Action;
import javax.annotation.Nonnull;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
public class Trie implements Comparable {
private final char c;
private final boolean terminal;
private final Trie[] transitions;
public static Trie from(String... words) {
return from(Arrays.asList(words));
}
public static Trie from(Iterable words) {
Builder builder = new Builder();
for (String word : words) {
builder.addWord(word);
}
return builder.build();
}
public static Builder builder() {
return new Trie.Builder();
}
private Trie(char c, boolean terminal, Trie[] transitions) {
this.c = c;
this.terminal = terminal;
this.transitions = transitions;
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append(c).append(terminal ? "(terminal)\n" : "\n");
sb.append("Next: ");
for (Trie transition : transitions) {
sb.append(transition.c).append(" ");
}
sb.append("\n");
return sb.toString();
}
@Override
public int compareTo(@Nonnull Trie o) {
return c - o.c;
}
/**
* Checks if the trie contains the given character sequence or any prefixes of the sequence.
*/
public boolean find(CharSequence seq) {
if (seq.length() == 0) {
return false;
}
int idx = 0;
Trie cur = this;
while (idx < seq.length()) {
char c = seq.charAt(idx);
boolean found = false;
for (Trie transition : cur.transitions) {
if (transition.c == c) {
cur = transition;
idx++;
found = true;
if (idx == seq.length()) {
return cur.terminal;
}
break;
} else if (transition.c > c) {
return false;
}
}
if (!found) {
return cur.terminal;
}
}
return cur.terminal;
}
public void dump(boolean all, Action super String> onWord) {
dump(new StringBuilder(), all, this, onWord);
}
private void dump(StringBuilder buffer, boolean all, Trie trie, Action super String> onWord) {
for (Trie transition : trie.transitions) {
buffer.append(transition.c);
if (transition.terminal) {
onWord.execute(buffer.toString());
if (all) {
dump(buffer, true, transition, onWord);
}
} else {
dump(buffer, all, transition, onWord);
}
buffer.setLength(buffer.length() - 1);
}
}
public static class Builder {
private final char c;
private boolean terminal;
private List transitions = new ArrayList();
public Builder() {
c = '\0';
}
private Builder(char c) {
this.c = c;
}
private Builder addTransition(char c, boolean terminal) {
Builder b = null;
for (Builder transition : transitions) {
if (transition.c == c) {
b = transition;
break;
}
}
if (b == null) {
b = new Builder(c);
transitions.add(b);
}
b.terminal |= terminal;
return b;
}
public void addWord(String word) {
Trie.Builder cur = this;
char[] chars = word.toCharArray();
for (int i = 0; i < chars.length; i++) {
char c = chars[i];
cur = cur.addTransition(c, i == chars.length - 1);
}
}
public Trie build() {
Trie[] transitions = new Trie[this.transitions.size()];
for (int i = 0; i < this.transitions.size(); i++) {
Builder transition = this.transitions.get(i);
transitions[i] = transition.build();
}
Arrays.sort(transitions);
return new Trie(c, terminal, transitions);
}
}
}
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