1324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver/* 2324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * [The "BSD license"] 3324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * Copyright (c) 2010 Terence Parr 4324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * All rights reserved. 5324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * 6324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * Redistribution and use in source and binary forms, with or without 7324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * modification, are permitted provided that the following conditions 8324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * are met: 9324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * 1. Redistributions of source code must retain the above copyright 10324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * notice, this list of conditions and the following disclaimer. 11324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * 2. Redistributions in binary form must reproduce the above copyright 12324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * notice, this list of conditions and the following disclaimer in the 13324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * documentation and/or other materials provided with the distribution. 14324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * 3. The name of the author may not be used to endorse or promote products 15324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * derived from this software without specific prior written permission. 16324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * 17324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 18324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 19324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 20324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 21324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 22324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 26324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver */ 28324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruverpackage org.antlr.misc; 29324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver 30324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruverimport java.util.ArrayList; 31324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruverimport java.util.LinkedHashMap; 32324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruverimport java.util.List; 33324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver 34324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver/** A hash table that maps a key to a list of elements not just a single. */ 35324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruverpublic class MultiMap<K, V> extends LinkedHashMap<K, List<V>> { 36324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver public void map(K key, V value) { 37324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver List<V> elementsForKey = get(key); 38324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver if ( elementsForKey==null ) { 39324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver elementsForKey = new ArrayList<V>(); 40324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver super.put(key, elementsForKey); 41324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver } 42324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver elementsForKey.add(value); 43324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver } 44324c4644fee44b9898524c09511bd33c3f12e2dfBen Gruver} 45