test/java/lang/ThreadGroup/Suspend.java
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@@ -1,7 +1,7 @@
/*
- * Copyright (c) 1999, Oracle and/or its affiliates. All rights reserved.
+ * 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.
@@ -21,49 +21,56 @@
* questions.
*/
/**
* @test
- * @bug 4176355
+ * @bug 4176355 7181748
* @summary Suspending a ThreadGroup that contains the current thread has
* unpredictable results.
*/
public class Suspend implements Runnable {
- private static Thread first=null;
- private static Thread second=null;
- private static ThreadGroup group = new ThreadGroup("");
- private static int count = 0;
-
- Suspend() {
- Thread thread = new Thread(group, this);
- if (first == null)
- first = thread;
- else
- second = thread;
- thread.start();
- }
+ private static 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(1000); // Give other thread a chance to start
- if (Thread.currentThread() == first)
+ Thread.sleep(100);
+ if (Thread.currentThread() == first) {
+ if (second.isAlive()) {
group.suspend();
- else
+ }
+ } else {
count++;
- } catch(InterruptedException e){
+ }
+ } catch (InterruptedException e) {
}
}
}
public static void main(String[] args) throws Exception {
- for (int i=0; i<2; i++)
- new Suspend();
- Thread.sleep(3000);
+ // 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();
+ first.stop();
+ second.stop();
if (failed)
throw new RuntimeException("Failure.");
}
}