/*
* FindBugs - Find Bugs in Java programs
* Copyright (C) 2003-2007 University of Maryland
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package edu.umd.cs.findbugs.util;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
/**
* @author William Pugh
*/
public class DualKeyHashMap<K1, K2, V> {
Map<K1, Map<K2, V>> map = new HashMap<K1, Map<K2, V>>();
public V get(K1 k1, K2 k2) {
Map<K2, V> m = map.get(k1);
if (m == null)
return null;
return m.get(k2);
}
public boolean containsKey(K1 k1, K2 k2) {
Map<K2, V> m = map.get(k1);
if (m == null)
return false;
return m.containsKey(k2);
}
public Map<K2, V> get(K1 k1) {
Map<K2, V> m = map.get(k1);
if (m == null)
return Collections.<K2, V> emptyMap();
return m;
}
public Set<K1> keySet() {
return map.keySet();
}
public V put(K1 k1, K2 k2, V v) {
Map<K2, V> m = map.get(k1);
if (m == null) {
m = Collections.singletonMap(k2, v);
map.put(k1, m);
return null;
} else if (m instanceof HashMap)
return m.put(k2, v);
else {
m = Util.makeSmallHashMap(m);
map.put(k1, m);
return m.put(k2, v);
}
}
}