/*
* Freeplane - mind map editor
* Copyright (C) 2008 Dimitry Polivaev
*
* This file author is Dimitry Polivaev
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.freeplane.core.util.collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
/**
* @author Dimitry Polivaev
* 06.01.2009
*/
public class MultipleValueMap<K, V> {
final private Map<K, List<V>> map;
public MultipleValueMap() {
super();
this.map = new HashMap<K, List<V>>();
}
public boolean containsKey(final Object key) {
return map.containsKey(key);
}
@SuppressWarnings("unchecked")
public List<V> get(final Object key) {
final List<V> list = map.get(key);
return list == null ? Collections.EMPTY_LIST : list;
}
// FIXME: value is not used - how should it? - VB
public List<V> put(final K key, final V value) {
List<V> list = map.get(key);
if (list == null) {
list = new LinkedList<V>();
map.put(key, list);
}
return list;
}
}