001/**
002 * Copyright 2011-2015 John Ericksen
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *    http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016package org.parceler;
017
018import java.util.ArrayList;
019import java.util.List;
020
021/**
022 * @author John Ericksen
023 */
024public final class IdentityCollection {
025
026    private static final Object RESERVATION = new Object();
027    private final List<Object> values = new ArrayList<Object>();
028
029    public IdentityCollection() {
030        put(null);
031    }
032
033    public boolean containsKey(int id){
034        return id < values.size();
035    }
036
037    public int reserve() {
038        return put(RESERVATION);
039    }
040
041    public boolean isReserved(int id) {
042        return values.get(id) == RESERVATION;
043    }
044
045    public void put(int id, Object input){
046        if(values.size() > id) {
047            values.remove(id);
048        }
049        values.add(id, input);
050    }
051
052    public int put(Object input) {
053        values.add(input);
054        return values.size() - 1;
055    }
056
057    @SuppressWarnings("unchecked")
058    public <T> T get(int id){
059        return (T) values.get(id);
060    }
061
062    public int getKey(Object input) {
063        for(int i = 0; i < values.size(); i++) {
064            if(values.get(i) == input) {
065                return i;
066            }
067        }
068        return -1;
069    }
070}