001    /*
002     *  This file is part of the Jikes RVM project (http://jikesrvm.org).
003     *
004     *  This file is licensed to You under the Eclipse Public License (EPL);
005     *  You may not use this file except in compliance with the License. You
006     *  may obtain a copy of the License at
007     *
008     *      http://www.opensource.org/licenses/eclipse-1.0.php
009     *
010     *  See the COPYRIGHT.txt file distributed with this work for information
011     *  regarding copyright ownership.
012     */
013    package org.jikesrvm.compilers.opt.util;
014    
015    /**
016     * An object that implements a bijection between whole numbers and
017     * objects.
018     */
019    public interface BitSetMapping {
020      /**
021       * Return the object numbered n.
022       */
023      Object getMappedObject(int n);
024    
025      /**
026       * Return the number of a given object.
027       */
028      int getMappedIndex(Object o);
029    
030      /**
031       * Return the size of the domain of the bijection.
032       */
033      int getMappingSize();
034    }