/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more 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
*
* 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 jpa.tools.swing;
import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
/**
* A map with indexed access.
* The keys are indexed in their order of insertion.
* The index of a given key is stable. It never changes unless the map is cleared.
* On <code>remove(k)</code>, the key is not removed, but its value is nullified.
* Then <code>indexOf(k)</code> will return <code>-1</code>.
*
*
* @author Pinaki Poddar
*
* @param <K>
* @param <V>
*/
public class IndexedMap<K,V> implements Map<K, V> {
private final List<K> _keys = new ArrayList<K>();
private final List<V> _values = new ArrayList<V>();
private final Set<K> _nulls = new HashSet<K>();
public void clear() {
_keys.clear();
_values.clear();
}
public boolean containsKey(Object key) {
return _keys.contains(key) && !_nulls.contains(key);
}
public boolean containsValue(Object value) {
return _values.contains(value);
}
/**
* Not supported.
*/
public Set<java.util.Map.Entry<K, V>> entrySet() {
throw new UnsupportedOperationException();
}
public V get(Object key) {
int i = indexOf(key);
return i == -1 ? null : _values.get(i);
}
public boolean isEmpty() {
return (_keys.size() - _nulls.size()) == 0;
}
public Set<K> keySet() {
Set<K> result = new HashSet<K>(_keys);
result.removeAll(_nulls);
return result;
}
public V put(K key, V value) {
int i = _keys.indexOf(key);
if (i == -1) {
_keys.add(key);
_values.add(value);
return null;
} else {
_nulls.remove(key);
return _values.set(i, value);
}
}
public void putAll(Map<? extends K, ? extends V> m) {
for (K k : m.keySet()) {
this.put(k, m.get(k));
}
}
@SuppressWarnings("unchecked")
public V remove(Object key) {
V v = get(key);
_nulls.add((K)key);
return v;
}
public int size() {
return _keys.size() - _nulls.size();
}
public Collection<V> values() {
Collection<V> result = new ArrayList<V>();
for (int i = 0; i < _values.size(); i++) {
if (!_nulls.contains(_keys.get(i)))
result.add(_values.get(i));
}
return result;
}
public int indexOf(Object key) {
return _keys.indexOf(key);
}
}