Java tutorial
/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License. You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ import java.util.Map; /** * Extended Version of {@link java.util.HashMap} that provides an extended * get method accpeting a default value. The default value is returned if * the map does not contain a value for the provided key. * * @version $Id: HashMap.java 587751 2007-10-24 02:41:36Z vgritsenko $ */ public class HashMap extends java.util.HashMap { public HashMap() { super(); } public HashMap(int initialCapacity) { super(initialCapacity); } public HashMap(int initialCapacity, float loadFactor) { super(initialCapacity, loadFactor); } public HashMap(Map t) { super(t); } /** * Get method extended by default object to be returned when key * is not found. * * @param key key to look up * @param _default default value to return if key is not found * @return value that is associated with key */ public Object get(Object key, Object _default) { if (this.containsKey(key)) { return this.get(key); } return _default; } }