    001/*
    002 * Licensed to the Apache Software Foundation (ASF) under one
    003 * or more contributor license agreements.  See the NOTICE file
    004 * distributed with this work for additional information
    005 * regarding copyright ownership.  The ASF licenses this file
    006 * to you under the Apache License, Version 2.0 (the
    007 * "License"); you may not use this file except in compliance
    008 * with the License.  You may obtain a copy of the License at
    009 *
    010 *   https://www.apache.org/licenses/LICENSE-2.0
    011 *
    012 * Unless required by applicable law or agreed to in writing,
    013 * software distributed under the License is distributed on an
    014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
    015 * KIND, either express or implied.  See the License for the
    016 * specific language governing permissions and limitations
    017 * under the License.
    018 */
    019package org.apache.bcel.util;
    020
    021import java.util.LinkedList;
    022
    023import org.apache.bcel.classfile.JavaClass;
    024
    025/**
    026 * Utility class implementing a (typesafe) queue of JavaClass objects.
    027 */
    028public class ClassQueue {
    029
    030    /**
    031     * @deprecated (since 6.0) will be made private; do not access
    032     */
    033    @Deprecated
    034    protected LinkedList<JavaClass> vec = new LinkedList<>(); // TODO not used externally
    035
    036    /**
    037     * Constructs a new ClassQueue.
    038     */
    039    public ClassQueue() {
    040    }
    041
    042    /**
    043     * Removes and returns the first JavaClass from the queue.
    044     *
    045     * @return the first JavaClass from the queue.
    046     */
    047    public JavaClass dequeue() {
    048        return vec.removeFirst();
    049    }
    050
    051    /**
    052     * Checks if the queue is empty.
    053     *
    054     * @return true if the queue is empty.
    055     */
    056    public boolean empty() {
    057        return vec.isEmpty();
    058    }
    059
    060    /**
    061     * Adds a JavaClass to the end of the queue.
    062     *
    063     * @param clazz the JavaClass to add.
    064     */
    065    public void enqueue(final JavaClass clazz) {
    066        vec.addLast(clazz);
    067    }
    068
    069    @Override
    070    public String toString() {
    071        return vec.toString();
    072    }
    073}