/*
* Copyright (c) 1999, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* questions.
*/
/**
* @test
* @bug 4176355 7181748
* @summary Suspending a ThreadGroup that contains the current thread has
* unpredictable results.
*/
public class Suspend implements Runnable {
private static volatile int count = 0;
private static final ThreadGroup group = new ThreadGroup("");
private static final Thread first = new Thread(group, new Suspend());
private static final Thread second = new Thread(group, new Suspend());
public void run() {
while (true) {
try {
Thread.sleep(100);
if (Thread.currentThread() == first) {
if (second.isAlive()) {
group.suspend();
}
} else {
count++;
}
} catch (InterruptedException e) {
}
}
}
public static void main(String[] args) throws Exception {
// Launch two threads as part of the same thread group
first.start();
second.start();
// Wait for the thread group suspend to be issued
while (!first.isAlive() || !second.isAlive()) {
Thread.sleep(100);
}
Thread.sleep(1000);
// Suppose, the thread group is now suspended
count = 0;
Thread.sleep(1000);
// Increment of the count indicates that the second thread is still running
boolean failed = (count > 1);
first.stop();
second.stop();
if (failed) {
throw new RuntimeException("Failure.");
}
}
}