001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     *  Unless required by applicable law or agreed to in writing, software
012     *  distributed under the License is distributed on an "AS IS" BASIS,
013     *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     *  See the License for the specific language governing permissions and
015     *  limitations under the License. 
016     *
017     */
018    package org.apache.bcel.util;
019    
020    import java.util.Stack;
021    import org.apache.bcel.classfile.JavaClass;
022    
023    /** 
024     * Utility class implementing a (typesafe) stack of JavaClass objects.
025     *
026     * @version $Id: ClassStack.java 1149459 2011-07-22 04:34:27Z dbrosius $
027     * @author <A HREF="mailto:m.dahm@gmx.de">M. Dahm</A> 
028     * @see Stack
029     */
030    public class ClassStack implements java.io.Serializable {
031    
032        private static final long serialVersionUID = 6126079269396985982L;
033        private Stack<JavaClass> stack = new Stack<JavaClass>();
034    
035    
036        public void push( JavaClass clazz ) {
037            stack.push(clazz);
038        }
039    
040    
041        public JavaClass pop() {
042            return stack.pop();
043        }
044    
045    
046        public JavaClass top() {
047            return stack.peek();
048        }
049    
050    
051        public boolean empty() {
052            return stack.empty();
053        }
054    }