1/*
2 * Copyright (c) 2013, 2015, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24/*
25 * @test
26 * @bug 8019623
27 * @summary Tests that AppContext.getAppContext() works correctly in multi-threads scenario.
28 * @author Leonid Romanov
29 * @modules java.desktop/sun.awt
30 */
31
32import sun.awt.AppContext;
33
34public class MultiThreadTest {
35    private static final int NUM_THREADS = 2;
36
37    private static AppContextGetter[] getters = new AppContextGetter[NUM_THREADS];
38
39    public static void main(String[] args) {
40        createAndStartThreads();
41        compareAppContexts();
42    }
43
44    private static void createAndStartThreads() {
45        ThreadGroup systemGroup = getSystemThreadGroup();
46        for (int i = 0; i < NUM_THREADS; ++i) {
47            ThreadGroup tg = new ThreadGroup(systemGroup, "AppContextGetter" + i);
48            getters[i] = new AppContextGetter(tg);
49        }
50
51        for (int i = 0; i < NUM_THREADS; ++i) {
52            getters[i].start();
53        }
54
55        for (int i = 0; i < NUM_THREADS; ++i) {
56            try {
57                getters[i].join();
58            } catch (InterruptedException e) {
59                // ignore
60            }
61        }
62    }
63
64    private static ThreadGroup getSystemThreadGroup() {
65        ThreadGroup currentThreadGroup =
66                Thread.currentThread().getThreadGroup();
67        ThreadGroup parentThreadGroup = currentThreadGroup.getParent();
68        while (parentThreadGroup != null) {
69            currentThreadGroup = parentThreadGroup;
70            parentThreadGroup = currentThreadGroup.getParent();
71        }
72
73        return currentThreadGroup;
74    }
75
76    private static void compareAppContexts() {
77        AppContext ctx = getters[0].getAppContext();
78        for (int i = 1; i < NUM_THREADS; ++i) {
79            if (!ctx.equals(getters[i].getAppContext())) {
80                throw new RuntimeException("Unexpected AppContexts difference, could be a race condition");
81            }
82        }
83    }
84
85    private static class AppContextGetter extends Thread {
86        private AppContext appContext;
87
88        public AppContextGetter(ThreadGroup tg) {
89            super(tg, tg.getName());
90        }
91
92        AppContext getAppContext() {
93            return appContext;
94        }
95
96        @Override
97        public void run() {
98            appContext = AppContext.getAppContext();
99        }
100    }
101}
102