--- jsr166/src/test/tck/ReentrantReadWriteLockTest.java	2017/01/01 20:34:39	1.79
+++ jsr166/src/test/tck/ReentrantReadWriteLockTest.java	2019/09/26 20:48:53	1.84
@@ -11,16 +11,17 @@ import static java.util.concurrent.TimeU
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.HashSet;
+import java.util.concurrent.Callable;
 import java.util.concurrent.CountDownLatch;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.locks.Condition;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantReadWriteLock;
 
-import junit.framework.AssertionFailedError;
 import junit.framework.Test;
 import junit.framework.TestSuite;
 
+@SuppressWarnings("WaitNotInLoop") // we implement spurious-wakeup freedom
 public class ReentrantReadWriteLockTest extends JSR166TestCase {
     public static void main(String[] args) {
         main(suite(), args);
@@ -87,7 +88,7 @@ public class ReentrantReadWriteLockTest
         long startTime = System.nanoTime();
         while (!lock.hasQueuedThread(t)) {
             if (millisElapsedSince(startTime) > LONG_DELAY_MS)
-                throw new AssertionFailedError("timed out");
+                throw new AssertionError("timed out");
             Thread.yield();
         }
         assertTrue(t.isAlive());
@@ -1009,42 +1010,41 @@ public class ReentrantReadWriteLockTest
     public void testAwaitUninterruptibly()      { testAwaitUninterruptibly(false); }
     public void testAwaitUninterruptibly_fair() { testAwaitUninterruptibly(true); }
     public void testAwaitUninterruptibly(boolean fair) {
-        final ReentrantReadWriteLock lock = new ReentrantReadWriteLock(fair);
-        final Condition c = lock.writeLock().newCondition();
+        final Lock lock = new ReentrantReadWriteLock(fair).writeLock();
+        final Condition condition = lock.newCondition();
         final CountDownLatch pleaseInterrupt = new CountDownLatch(2);
 
         Thread t1 = newStartedThread(new CheckedRunnable() {
             public void realRun() {
                 // Interrupt before awaitUninterruptibly
-                lock.writeLock().lock();
+                lock.lock();
                 pleaseInterrupt.countDown();
                 Thread.currentThread().interrupt();
-                c.awaitUninterruptibly();
+                condition.awaitUninterruptibly();
                 assertTrue(Thread.interrupted());
-                lock.writeLock().unlock();
+                lock.unlock();
             }});
 
         Thread t2 = newStartedThread(new CheckedRunnable() {
             public void realRun() {
                 // Interrupt during awaitUninterruptibly
-                lock.writeLock().lock();
+                lock.lock();
                 pleaseInterrupt.countDown();
-                c.awaitUninterruptibly();
+                condition.awaitUninterruptibly();
                 assertTrue(Thread.interrupted());
-                lock.writeLock().unlock();
+                lock.unlock();
             }});
 
         await(pleaseInterrupt);
-        lock.writeLock().lock();
-        lock.writeLock().unlock();
         t2.interrupt();
-
-        assertThreadStaysAlive(t1);
-        assertTrue(t2.isAlive());
-
-        lock.writeLock().lock();
-        c.signalAll();
-        lock.writeLock().unlock();
+        lock.lock();
+        lock.unlock();
+        assertThreadBlocks(t1, Thread.State.WAITING);
+        assertThreadBlocks(t2, Thread.State.WAITING);
+
+        lock.lock();
+        condition.signalAll();
+        lock.unlock();
 
         awaitTermination(t1);
         awaitTermination(t2);
@@ -1681,4 +1681,64 @@ public class ReentrantReadWriteLockTest
         assertTrue(lock.writeLock().toString().contains("Unlocked"));
     }
 
+    /**
+     * ThreadMXBean reports the blockers that we expect.
+     */
+    public void testBlockers() {
+        if (!testImplementationDetails) return;
+        final boolean fair = randomBoolean();
+        final boolean timedAcquire = randomBoolean();
+        final boolean timedAwait = randomBoolean();
+        final String syncClassName = fair
+            ? "ReentrantReadWriteLock$FairSync"
+            : "ReentrantReadWriteLock$NonfairSync";
+        final String conditionClassName
+            = "AbstractQueuedSynchronizer$ConditionObject";
+        final Thread.State expectedAcquireState = timedAcquire
+            ? Thread.State.TIMED_WAITING
+            : Thread.State.WAITING;
+        final Thread.State expectedAwaitState = timedAwait
+            ? Thread.State.TIMED_WAITING
+            : Thread.State.WAITING;
+        final Lock lock = new ReentrantReadWriteLock(fair).writeLock();
+        final Condition condition = lock.newCondition();
+        final AtomicBoolean conditionSatisfied = new AtomicBoolean(false);
+        lock.lock();
+        final Thread thread = newStartedThread((Action) () -> {
+            if (timedAcquire)
+                lock.tryLock(LONGER_DELAY_MS, MILLISECONDS);
+            else
+                lock.lock();
+            while (!conditionSatisfied.get())
+                if (timedAwait)
+                    condition.await(LONGER_DELAY_MS, MILLISECONDS);
+                else
+                    condition.await();
+        });
+        Callable<Boolean> waitingForLock = () -> {
+            String className;
+            return thread.getState() == expectedAcquireState
+            && (className = blockerClassName(thread)) != null
+            && className.endsWith(syncClassName);
+        };
+        waitForThreadToEnterWaitState(thread, waitingForLock);
+
+        lock.unlock();
+        Callable<Boolean> waitingForCondition = () -> {
+            String className;
+            return thread.getState() == expectedAwaitState
+            && (className = blockerClassName(thread)) != null
+            && className.endsWith(conditionClassName);
+        };
+        waitForThreadToEnterWaitState(thread, waitingForCondition);
+
+        // politely release the waiter
+        conditionSatisfied.set(true);
+        lock.lock();
+        try {
+            condition.signal();
+        } finally { lock.unlock(); }
+
+        awaitTermination(thread);
+    }
 }