1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * https://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.apache.bcel.util;
20
21 import java.util.LinkedList;
22
23 import org.apache.bcel.classfile.JavaClass;
24
25 /**
26 * Utility class implementing a (typesafe) queue of JavaClass objects.
27 */
28 public class ClassQueue {
29
30 /**
31 * @deprecated (since 6.0) will be made private; do not access
32 */
33 @Deprecated
34 protected LinkedList<JavaClass> vec = new LinkedList<>(); // TODO not used externally
35
36 /**
37 * Constructs a new ClassQueue.
38 */
39 public ClassQueue() {
40 }
41
42 /**
43 * Removes and returns the first JavaClass from the queue.
44 *
45 * @return the first JavaClass from the queue.
46 */
47 public JavaClass dequeue() {
48 return vec.removeFirst();
49 }
50
51 /**
52 * Checks if the queue is empty.
53 *
54 * @return true if the queue is empty.
55 */
56 public boolean empty() {
57 return vec.isEmpty();
58 }
59
60 /**
61 * Adds a JavaClass to the end of the queue.
62 *
63 * @param clazz the JavaClass to add.
64 */
65 public void enqueue(final JavaClass clazz) {
66 vec.addLast(clazz);
67 }
68
69 @Override
70 public String toString() {
71 return vec.toString();
72 }
73 }