001 /*--------------------------------------------------------------------------+ 002 $Id: UniqueIdManager.java 26283 2010-02-18 11:18:57Z juergens $ 003 | | 004 | Copyright 2005-2010 Technische Universitaet Muenchen | 005 | | 006 | Licensed under the Apache License, Version 2.0 (the "License"); | 007 | you may not use this file except in compliance with the License. | 008 | You may obtain a copy of the License at | 009 | | 010 | http://www.apache.org/licenses/LICENSE-2.0 | 011 | | 012 | Unless required by applicable law or agreed to in writing, software | 013 | distributed under the License is distributed on an "AS IS" BASIS, | 014 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | 015 | See the License for the specific language governing permissions and | 016 | limitations under the License. | 017 +--------------------------------------------------------------------------*/ 018 package edu.tum.cs.commons.collections; 019 020 import java.util.IdentityHashMap; 021 022 /** 023 * This class assigns unique ids to objects. The id creation is based on 024 * <b>referential equality</b> instead of <code>hashCode()/equals()</code>-semantics. 025 * 026 * <p> 027 * Note that obtaining a unique id from this class for an object prevents it 028 * from being garbage collected. 029 * 030 * 031 * @author Florian Deissenboeck 032 * @author $Author: juergens $ 033 * @version $Rev: 26283 $ 034 * @levd.rating GREEN Hash: BB79C9D841FE57B450865418AFDD8E6F 035 */ 036 public class UniqueIdManager<K> extends IdManagerBase<K> { 037 038 /** 039 * Create new unique id manager. 040 * 041 */ 042 public UniqueIdManager() { 043 super(new IdentityHashMap<K, Integer>()); 044 } 045 046 }