| /* |
| * Copyright 2015 Open Networking Laboratory |
| * |
| * Licensed 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. |
| */ |
| |
| package org.onlab.util; |
| |
| import java.util.HashMap; |
| |
| /** |
| * HashMap that returns a default value for unmapped keys. |
| */ |
| public final class DefaultHashMap<K, V> extends HashMap<K, V> { |
| |
| /** Default value to return when no key binding exists. */ |
| protected final V defaultValue; |
| |
| /** |
| * Constructs an empty map with the given default value. |
| * |
| * @param defaultValue the default value |
| */ |
| public DefaultHashMap(V defaultValue) { |
| this.defaultValue = defaultValue; |
| } |
| |
| @Override |
| public V get(Object k) { |
| return containsKey(k) ? super.get(k) : defaultValue; |
| } |
| } |