/**************************************************************************
OmegaT - Computer Assisted Translation (CAT) tool
with fuzzy matching, translation memory, keyword search,
glossaries, and translation leveraging into updated projects.
Copyright (C) 2000-2006 Keith Godfrey and Maxym Mykhalchuk
Home page: http://www.omegat.org/
Support center: http://groups.yahoo.com/group/OmegaT/
This file is part of OmegaT.
OmegaT 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 3 of the License, or
(at your option) any later version.
OmegaT 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.omegat.util;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;
/**
* A map that maps keys to sets of values. Does NOT allow null keys/values.
*
* @author Maxym Mykhalchuk
*/
public class MultiMap<K, V> {
/** We're backed up by a HashMap<key, HashSet>. */
Map<K, Set<V>> map;
/** Creates an empty MultiMap. */
public MultiMap() {
map = new HashMap<K, Set<V>>();
}
/**
* Returns <tt>true</tt> if this map contains a mapping for the specified
* key.
*/
public boolean containsKey(K key) {
return map.containsKey(key);
}
/**
* Returns <tt>true</tt> if this map maps the specified key to the specified
* value.
*/
public boolean containsPair(K key, V value) {
if (containsKey(key)) {
Set<V> values = map.get(key);
return values.contains(value);
} else
return false;
}
/**
* Associates the specified value with the specified key in this multi-map.
* Unlike normal Map, if the map previously contained a mapping for this
* key, the new value is appended to the list of the values mapped from this
* key.
*/
public void put(K key, V value) {
if (containsKey(key)) {
Set<V> values = map.get(key);
values.add(value);
} else {
Set<V> values = new HashSet<V>();
values.add(value);
map.put(key, values);
}
}
/** Removes all the mappings for this key from this map if it is present. */
public void remove(Object key) {
map.remove(key);
}
}