001    /**
002     * Copyright (c) 2000-2010 Liferay, Inc. All rights reserved.
003     *
004     * This library is free software; you can redistribute it and/or modify it under
005     * the terms of the GNU Lesser General Public License as published by the Free
006     * Software Foundation; either version 2.1 of the License, or (at your option)
007     * any later version.
008     *
009     * This library is distributed in the hope that it will be useful, but WITHOUT
010     * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
011     * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
012     * details.
013     */
014    
015    package com.liferay.util;
016    
017    import java.util.Stack;
018    
019    /**
020     * @author Brian Wing Shun Chan
021     */
022    public class FiniteStack<E> extends Stack<E> {
023    
024            public FiniteStack(int maxSize) {
025                    super();
026    
027                    _maxSize = maxSize;
028            }
029    
030            public E push(E item) {
031                    super.push(item);
032    
033                    int size = size();
034    
035                    if (size > _maxSize) {
036                            removeElementAt(size - 1);
037                    }
038    
039                    return item;
040            }
041    
042            private int _maxSize;
043    
044    }