001 /** 002 * Copyright (c) 2000-present 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 _maxSize = maxSize; 026 } 027 028 @Override 029 public E push(E item) { 030 super.push(item); 031 032 int size = size(); 033 034 if (size > _maxSize) { 035 removeElementAt(size - 1); 036 } 037 038 return item; 039 } 040 041 private final int _maxSize; 042 043 }