Java tutorial
/* * Copyright (c) 2012 The Broad Institute * * Permission is hereby granted, free of charge, to any person * obtaining a copy of this software and associated documentation * files (the "Software"), to deal in the Software without * restriction, including without limitation the rights to use, * copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following * conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR * THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package org.broadinstitute.sting.utils.collections; import java.util.HashMap; /** * Created with IntelliJ IDEA. * User: farjoun * Date: 10/30/12 * Time: 3:20 PM * To change this template use File | Settings | File Templates. */ //lifted from http://stackoverflow.com/questions/7519339 //could also use org.apache.commons.collections.map.DefaultedMap http://commons.apache.org/collections/apidocs/org/apache/commons/collections/map/DefaultedMap.html public class DefaultHashMap<K, V> extends HashMap<K, V> { public void setDefaultValue(V defaultValue) { this.defaultValue = defaultValue; } protected V defaultValue; public DefaultHashMap(V defaultValue) { this.defaultValue = defaultValue; } @Override public V get(Object k) { V v = super.get(k); return ((v == null) && !this.containsKey(k)) ? this.defaultValue : v; } }