6633113: test/java/util/concurrent/SynchronousQueue/Fairness.java fails intermittently
Reviewed-by: dholmes
--- a/jdk/test/java/util/concurrent/SynchronousQueue/Fairness.java Mon Mar 10 23:23:47 2008 -0700
+++ b/jdk/test/java/util/concurrent/SynchronousQueue/Fairness.java Mon Mar 10 23:23:48 2008 -0700
@@ -23,36 +23,49 @@
/*
* @test
- * @bug 4992438
- * @compile -source 1.5 Fairness.java
- * @run main Fairness
+ * @bug 4992438 6633113
* @summary Checks that fairness setting is respected.
*/
import java.util.concurrent.*;
+import java.util.concurrent.locks.*;
public class Fairness {
private static void testFairness(boolean fair,
final BlockingQueue<Integer> q)
- throws Exception
+ throws Throwable
{
- for (int i = 0; i < 3; i++) {
- final Integer I = new Integer(i);
- new Thread() { public void run() {
- try { q.put(I); } catch (Exception e) {}
- }}.start();
- Thread.currentThread().sleep(100);
+ final ReentrantLock lock = new ReentrantLock();
+ final Condition ready = lock.newCondition();
+ final int threadCount = 10;
+ final Throwable[] badness = new Throwable[1];
+ lock.lock();
+ for (int i = 0; i < threadCount; i++) {
+ final Integer I = i;
+ Thread t = new Thread() { public void run() {
+ try {
+ lock.lock();
+ ready.signal();
+ lock.unlock();
+ q.put(I);
+ } catch (Throwable t) { badness[0] = t; }}};
+ t.start();
+ ready.await();
+ // Probably unnecessary, but should be bullet-proof
+ while (t.getState() == Thread.State.RUNNABLE)
+ Thread.yield();
}
- for (int i = 0; i < 3; i++) {
- int j = q.take().intValue();
- System.err.printf("%d%n",j);
+ for (int i = 0; i < threadCount; i++) {
+ int j = q.take();
// Non-fair queues are lifo in our implementation
- if (fair ? j != i : j != 2-i)
- throw new Exception("No fair!");
+ if (fair ? j != i : j != threadCount - 1 - i)
+ throw new Error(String.format("fair=%b i=%d j=%d%n",
+ fair, i, j));
}
+ if (badness[0] != null) throw new Error(badness[0]);
}
- public static void main(String[] args) throws Exception {
+ public static void main(String[] args) throws Throwable {
testFairness(false, new SynchronousQueue<Integer>());
testFairness(false, new SynchronousQueue<Integer>(false));
testFairness(true, new SynchronousQueue<Integer>(true));