/*
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 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You 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
 *
 *      https://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,
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package org.apache.tools.ant.util;

import java.util.Collection;
import java.util.Collections;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Set;

Subclass of Hashtable that wraps a LinkedHashMap to provide predictable iteration order.

This is not a general purpose class but has been written because the protected members of Copy prohibited later revisions from using a more predictable collection.

Methods are synchronized to keep Hashtable's contract.

Since:Ant 1.8.2
/** * Subclass of Hashtable that wraps a LinkedHashMap to provide * predictable iteration order. * * <p>This is not a general purpose class but has been written because * the protected members of {@link org.apache.tools.ant.taskdefs.Copy * Copy} prohibited later revisions from using a more predictable * collection.</p> * * <p>Methods are synchronized to keep Hashtable's contract.</p> * * @since Ant 1.8.2 */
public class LinkedHashtable<K, V> extends Hashtable<K, V> { private static final long serialVersionUID = 1L; private final LinkedHashMap<K, V> map; public LinkedHashtable() { map = new LinkedHashMap<>(); } public LinkedHashtable(int initialCapacity) { map = new LinkedHashMap<>(initialCapacity); } public LinkedHashtable(int initialCapacity, float loadFactor) { map = new LinkedHashMap<>(initialCapacity, loadFactor); } public LinkedHashtable(Map<K, V> m) { map = new LinkedHashMap<>(m); } public synchronized void clear() { map.clear(); } @Override public boolean contains(Object value) { return containsKey(value); } @Override public synchronized boolean containsKey(Object value) { return map.containsKey(value); } @Override public synchronized boolean containsValue(Object value) { return map.containsValue(value); } @Override public Enumeration<V> elements() { return Collections.enumeration(values()); } @Override public synchronized Set<Map.Entry<K, V>> entrySet() { return map.entrySet(); } @Override public synchronized boolean equals(Object o) { return map.equals(o); } @Override public synchronized V get(Object k) { return map.get(k); } @Override public synchronized int hashCode() { return map.hashCode(); } @Override public synchronized boolean isEmpty() { return map.isEmpty(); } @Override public Enumeration<K> keys() { return Collections.enumeration(keySet()); } @Override public synchronized Set<K> keySet() { return map.keySet(); } @Override public synchronized V put(K k, V v) { return map.put(k, v); } @Override public synchronized void putAll(Map<? extends K, ? extends V> m) { map.putAll(m); } @Override public synchronized V remove(Object k) { return map.remove(k); } @Override public synchronized int size() { return map.size(); } @Override public synchronized String toString() { return map.toString(); } @Override public synchronized Collection<V> values() { return map.values(); } }