1 /*
2 * Copyright (c) 2002-2025 Gargoyle Software Inc.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 * https://www.apache.org/licenses/LICENSE-2.0
8 *
9 * Unless required by applicable law or agreed to in writing, software
10 * distributed under the License is distributed on an "AS IS" BASIS,
11 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 * See the License for the specific language governing permissions and
13 * limitations under the License.
14 */
15 package org.htmlunit;
16
17 import java.io.IOException;
18 import java.io.ObjectInputStream;
19 import java.lang.ref.WeakReference;
20
21 import org.apache.commons.logging.Log;
22 import org.apache.commons.logging.LogFactory;
23 import org.htmlunit.html.HtmlPage;
24
25 /**
26 * This {@link AjaxController} resynchronizes calls calling from the main thread.
27 * The idea is that asynchronous AJAX calls performed directly in response to a user
28 * action (therefore in the "main" thread and not in the thread of a background task)
29 * are directly useful for the user. To easily have a testable state, these calls
30 * are performed synchronously.
31 *
32 * @author Marc Guillemot
33 */
34 public class NicelyResynchronizingAjaxController extends AjaxController {
35
36 private static final Log LOG = LogFactory.getLog(NicelyResynchronizingAjaxController.class);
37
38 private transient WeakReference<Thread> originatedThread_;
39
40 /**
41 * Creates an instance.
42 */
43 public NicelyResynchronizingAjaxController() {
44 super();
45 init();
46 }
47
48 /**
49 * Initializes this instance.
50 */
51 private void init() {
52 originatedThread_ = new WeakReference<>(Thread.currentThread());
53 }
54
55 /**
56 * Resynchronizes calls performed from the thread where this instance has been created.
57 * <p>
58 * {@inheritDoc}
59 */
60 @Override
61 public boolean processSynchron(final HtmlPage page, final WebRequest settings, final boolean async) {
62 if (async && isInOriginalThread()) {
63 LOG.info("Re-synchronized call to " + settings.getUrl());
64 return true;
65 }
66 return !async;
67 }
68
69 /**
70 * Indicates if the currently executing thread is the one in which this instance has been created.
71 * @return {@code true} if it's the same thread
72 */
73 boolean isInOriginalThread() {
74 return Thread.currentThread() == originatedThread_.get();
75 }
76
77 /**
78 * Custom deserialization logic.
79 * @param stream the stream from which to read the object
80 * @throws IOException if an IO error occurs
81 * @throws ClassNotFoundException if a class cannot be found
82 */
83 private void readObject(final ObjectInputStream stream) throws IOException, ClassNotFoundException {
84 stream.defaultReadObject();
85 init();
86 }
87
88 }