/*
* Written by Doug Lea with assistance from members of JCP JSR-166
* Expert Group and released to the public domain, as explained at
* http://creativecommons.org/publicdomain/zero/1.0/
* Other contributors include Andrew Wright, Jeffrey Hayes,
* Pat Fisher, Mike Judd.
*/
package jsr166;
import static java.util.concurrent.TimeUnit.MILLISECONDS;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashSet;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.CyclicBarrier;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.ReentrantLock;
import junit.framework.AssertionFailedError;
import junit.framework.Test;
import junit.framework.TestSuite;
public class ReentrantLockTest extends JSR166TestCase {
// android-note: Removed because the CTS runner does a bad job of
// retrying tests that have suite() declarations.
//
// public static void main(String[] args) {
// main(suite(), args);
// }
// public static Test suite() {
// return new TestSuite(ReentrantLockTest.class);
// }
/**
* A checked runnable calling lockInterruptibly
*/
class InterruptibleLockRunnable extends CheckedRunnable {
final ReentrantLock lock;
InterruptibleLockRunnable(ReentrantLock lock) { this.lock = lock; }
public void realRun() throws InterruptedException {
lock.lockInterruptibly();
}
}
/**
* A checked runnable calling lockInterruptibly that expects to be
* interrupted
*/
class InterruptedLockRunnable extends CheckedInterruptedRunnable {
final ReentrantLock lock;
InterruptedLockRunnable(ReentrantLock lock) { this.lock = lock; }
public void realRun() throws InterruptedException {
lock.lockInterruptibly();
}
}
/**
* Subclass to expose protected methods
*/
static class PublicReentrantLock extends ReentrantLock {
PublicReentrantLock() { super(); }
PublicReentrantLock(boolean fair) { super(fair); }
public Thread getOwner() {
return super.getOwner();
}
public Collection<Thread> getQueuedThreads() {
return super.getQueuedThreads();
}
public Collection<Thread> getWaitingThreads(Condition c) {
return super.getWaitingThreads(c);
}
}
/**
* Releases write lock, checking that it had a hold count of 1.
*/
void releaseLock(PublicReentrantLock lock) {
assertLockedByMoi(lock);
lock.unlock();
assertFalse(lock.isHeldByCurrentThread());
assertNotLocked(lock);
}
/**
* Spin-waits until lock.hasQueuedThread(t) becomes true.
*/
void waitForQueuedThread(PublicReentrantLock lock, Thread t) {
long startTime = System.nanoTime();
while (!lock.hasQueuedThread(t)) {
if (millisElapsedSince(startTime) > LONG_DELAY_MS)
throw new AssertionFailedError("timed out");
Thread.yield();
}
assertTrue(t.isAlive());
assertNotSame(t, lock.getOwner());
}
/**
* Checks that lock is not locked.
*/
void assertNotLocked(PublicReentrantLock lock) {
assertFalse(lock.isLocked());
assertFalse(lock.isHeldByCurrentThread());
assertNull(lock.getOwner());
assertEquals(0, lock.getHoldCount());
}
/**
* Checks that lock is locked by the given thread.
*/
void assertLockedBy(PublicReentrantLock lock, Thread t) {
assertTrue(lock.isLocked());
assertSame(t, lock.getOwner());
assertEquals(t == Thread.currentThread(),
lock.isHeldByCurrentThread());
assertEquals(t == Thread.currentThread(),
lock.getHoldCount() > 0);
}
/**
* Checks that lock is locked by the current thread.
*/
void assertLockedByMoi(PublicReentrantLock lock) {
assertLockedBy(lock, Thread.currentThread());
}
/**
* Checks that condition c has no waiters.
*/
void assertHasNoWaiters(PublicReentrantLock lock, Condition c) {
assertHasWaiters(lock, c, new Thread[] {});
}
/**
* Checks that condition c has exactly the given waiter threads.
*/
void assertHasWaiters(PublicReentrantLock lock, Condition c,
Thread... threads) {
lock.lock();
assertEquals(threads.length > 0, lock.hasWaiters(c));
assertEquals(threads.length, lock.getWaitQueueLength(c));
assertEquals(threads.length == 0, lock.getWaitingThreads(c).isEmpty());
assertEquals(threads.length, lock.getWaitingThreads(c).size());
assertEquals(new HashSet<Thread>(lock.getWaitingThreads(c)),
new HashSet<Thread>(Arrays.asList(threads)));
lock.unlock();
}
enum AwaitMethod { await, awaitTimed, awaitNanos, awaitUntil }
/**
* Awaits condition "indefinitely" using the specified AwaitMethod.
*/
void await(Condition c, AwaitMethod awaitMethod)
throws InterruptedException {
long timeoutMillis = 2 * LONG_DELAY_MS;
switch (awaitMethod) {
case await:
c.await();
break;
case awaitTimed:
assertTrue(c.await(timeoutMillis, MILLISECONDS));
break;
case awaitNanos:
long timeoutNanos = MILLISECONDS.toNanos(timeoutMillis);
long nanosRemaining = c.awaitNanos(timeoutNanos);
assertTrue(nanosRemaining > timeoutNanos / 2);
assertTrue(nanosRemaining <= timeoutNanos);
break;
case awaitUntil:
assertTrue(c.awaitUntil(delayedDate(timeoutMillis)));
break;
default:
throw new AssertionError();
}
}
/**
* Constructor sets given fairness, and is in unlocked state
*/
public void testConstructor() {
PublicReentrantLock lock;
lock = new PublicReentrantLock();
assertFalse(lock.isFair());
assertNotLocked(lock);
lock = new PublicReentrantLock(true);
assertTrue(lock.isFair());
assertNotLocked(lock);
lock = new PublicReentrantLock(false);
assertFalse(lock.isFair());
assertNotLocked(lock);
}
/**
* locking an unlocked lock succeeds
*/
public void testLock() { testLock(false); }
public void testLock_fair() { testLock(true); }
public void testLock(boolean fair) {
PublicReentrantLock lock = new PublicReentrantLock(fair);
lock.lock();
assertLockedByMoi(lock);
releaseLock(lock);
}
/**
* Unlocking an unlocked lock throws IllegalMonitorStateException
*/
public void testUnlock_IMSE() { testUnlock_IMSE(false); }
public void testUnlock_IMSE_fair() { testUnlock_IMSE(true); }
public void testUnlock_IMSE(boolean fair) {
ReentrantLock lock = new ReentrantLock(fair);
try {
lock.unlock();
shouldThrow();
} catch (IllegalMonitorStateException success) {}
}
/**
* tryLock on an unlocked lock succeeds
*/
public void testTryLock() { testTryLock(false); }
public void testTryLock_fair() { testTryLock(true); }
public void testTryLock(boolean fair) {
PublicReentrantLock lock = new PublicReentrantLock(fair);
assertTrue(lock.tryLock());
assertLockedByMoi(lock);
assertTrue(lock.tryLock());
assertLockedByMoi(lock);
lock.unlock();
releaseLock(lock);
}
/**
* hasQueuedThreads reports whether there are waiting threads
*/
public void testHasQueuedThreads() { testHasQueuedThreads(false); }
public void testHasQueuedThreads_fair() { testHasQueuedThreads(true); }
public void testHasQueuedThreads(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
Thread t1 = new Thread(new InterruptedLockRunnable(lock));
Thread t2 = new Thread(new InterruptibleLockRunnable(lock));
assertFalse(lock.hasQueuedThreads());
lock.lock();
assertFalse(lock.hasQueuedThreads());
t1.start();
waitForQueuedThread(lock, t1);
assertTrue(lock.hasQueuedThreads());
t2.start();
waitForQueuedThread(lock, t2);
assertTrue(lock.hasQueuedThreads());
t1.interrupt();
awaitTermination(t1);
assertTrue(lock.hasQueuedThreads());
lock.unlock();
awaitTermination(t2);
assertFalse(lock.hasQueuedThreads());
}
/**
* getQueueLength reports number of waiting threads
*/
public void testGetQueueLength() { testGetQueueLength(false); }
public void testGetQueueLength_fair() { testGetQueueLength(true); }
public void testGetQueueLength(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
Thread t1 = new Thread(new InterruptedLockRunnable(lock));
Thread t2 = new Thread(new InterruptibleLockRunnable(lock));
assertEquals(0, lock.getQueueLength());
lock.lock();
t1.start();
waitForQueuedThread(lock, t1);
assertEquals(1, lock.getQueueLength());
t2.start();
waitForQueuedThread(lock, t2);
assertEquals(2, lock.getQueueLength());
t1.interrupt();
awaitTermination(t1);
assertEquals(1, lock.getQueueLength());
lock.unlock();
awaitTermination(t2);
assertEquals(0, lock.getQueueLength());
}
/**
* hasQueuedThread(null) throws NPE
*/
public void testHasQueuedThreadNPE() { testHasQueuedThreadNPE(false); }
public void testHasQueuedThreadNPE_fair() { testHasQueuedThreadNPE(true); }
public void testHasQueuedThreadNPE(boolean fair) {
final ReentrantLock lock = new ReentrantLock(fair);
try {
lock.hasQueuedThread(null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* hasQueuedThread reports whether a thread is queued
*/
public void testHasQueuedThread() { testHasQueuedThread(false); }
public void testHasQueuedThread_fair() { testHasQueuedThread(true); }
public void testHasQueuedThread(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
Thread t1 = new Thread(new InterruptedLockRunnable(lock));
Thread t2 = new Thread(new InterruptibleLockRunnable(lock));
assertFalse(lock.hasQueuedThread(t1));
assertFalse(lock.hasQueuedThread(t2));
lock.lock();
t1.start();
waitForQueuedThread(lock, t1);
assertTrue(lock.hasQueuedThread(t1));
assertFalse(lock.hasQueuedThread(t2));
t2.start();
waitForQueuedThread(lock, t2);
assertTrue(lock.hasQueuedThread(t1));
assertTrue(lock.hasQueuedThread(t2));
t1.interrupt();
awaitTermination(t1);
assertFalse(lock.hasQueuedThread(t1));
assertTrue(lock.hasQueuedThread(t2));
lock.unlock();
awaitTermination(t2);
assertFalse(lock.hasQueuedThread(t1));
assertFalse(lock.hasQueuedThread(t2));
}
/**
* getQueuedThreads includes waiting threads
*/
public void testGetQueuedThreads() { testGetQueuedThreads(false); }
public void testGetQueuedThreads_fair() { testGetQueuedThreads(true); }
public void testGetQueuedThreads(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
Thread t1 = new Thread(new InterruptedLockRunnable(lock));
Thread t2 = new Thread(new InterruptibleLockRunnable(lock));
assertTrue(lock.getQueuedThreads().isEmpty());
lock.lock();
assertTrue(lock.getQueuedThreads().isEmpty());
t1.start();
waitForQueuedThread(lock, t1);
assertEquals(1, lock.getQueuedThreads().size());
assertTrue(lock.getQueuedThreads().contains(t1));
t2.start();
waitForQueuedThread(lock, t2);
assertEquals(2, lock.getQueuedThreads().size());
assertTrue(lock.getQueuedThreads().contains(t1));
assertTrue(lock.getQueuedThreads().contains(t2));
t1.interrupt();
awaitTermination(t1);
assertFalse(lock.getQueuedThreads().contains(t1));
assertTrue(lock.getQueuedThreads().contains(t2));
assertEquals(1, lock.getQueuedThreads().size());
lock.unlock();
awaitTermination(t2);
assertTrue(lock.getQueuedThreads().isEmpty());
}
/**
* timed tryLock is interruptible
*/
public void testTryLock_Interruptible() { testTryLock_Interruptible(false); }
public void testTryLock_Interruptible_fair() { testTryLock_Interruptible(true); }
public void testTryLock_Interruptible(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
lock.lock();
Thread t = newStartedThread(new CheckedInterruptedRunnable() {
public void realRun() throws InterruptedException {
lock.tryLock(2 * LONG_DELAY_MS, MILLISECONDS);
}});
waitForQueuedThread(lock, t);
t.interrupt();
awaitTermination(t);
releaseLock(lock);
}
/**
* tryLock on a locked lock fails
*/
public void testTryLockWhenLocked() { testTryLockWhenLocked(false); }
public void testTryLockWhenLocked_fair() { testTryLockWhenLocked(true); }
public void testTryLockWhenLocked(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
lock.lock();
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() {
assertFalse(lock.tryLock());
}});
awaitTermination(t);
releaseLock(lock);
}
/**
* Timed tryLock on a locked lock times out
*/
public void testTryLock_Timeout() { testTryLock_Timeout(false); }
public void testTryLock_Timeout_fair() { testTryLock_Timeout(true); }
public void testTryLock_Timeout(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
lock.lock();
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
long startTime = System.nanoTime();
long timeoutMillis = 10;
assertFalse(lock.tryLock(timeoutMillis, MILLISECONDS));
assertTrue(millisElapsedSince(startTime) >= timeoutMillis);
}});
awaitTermination(t);
releaseLock(lock);
}
/**
* getHoldCount returns number of recursive holds
*/
public void testGetHoldCount() { testGetHoldCount(false); }
public void testGetHoldCount_fair() { testGetHoldCount(true); }
public void testGetHoldCount(boolean fair) {
ReentrantLock lock = new ReentrantLock(fair);
for (int i = 1; i <= SIZE; i++) {
lock.lock();
assertEquals(i, lock.getHoldCount());
}
for (int i = SIZE; i > 0; i--) {
lock.unlock();
assertEquals(i - 1, lock.getHoldCount());
}
}
/**
* isLocked is true when locked and false when not
*/
public void testIsLocked() { testIsLocked(false); }
public void testIsLocked_fair() { testIsLocked(true); }
public void testIsLocked(boolean fair) {
try {
final ReentrantLock lock = new ReentrantLock(fair);
assertFalse(lock.isLocked());
lock.lock();
assertTrue(lock.isLocked());
lock.lock();
assertTrue(lock.isLocked());
lock.unlock();
assertTrue(lock.isLocked());
lock.unlock();
assertFalse(lock.isLocked());
final CyclicBarrier barrier = new CyclicBarrier(2);
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() throws Exception {
lock.lock();
assertTrue(lock.isLocked());
barrier.await();
barrier.await();
lock.unlock();
}});
barrier.await();
assertTrue(lock.isLocked());
barrier.await();
awaitTermination(t);
assertFalse(lock.isLocked());
} catch (Exception fail) { threadUnexpectedException(fail); }
}
/**
* lockInterruptibly succeeds when unlocked, else is interruptible
*/
public void testLockInterruptibly() { testLockInterruptibly(false); }
public void testLockInterruptibly_fair() { testLockInterruptibly(true); }
public void testLockInterruptibly(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
try {
lock.lockInterruptibly();
} catch (InterruptedException fail) { threadUnexpectedException(fail); }
assertLockedByMoi(lock);
Thread t = newStartedThread(new InterruptedLockRunnable(lock));
waitForQueuedThread(lock, t);
t.interrupt();
assertTrue(lock.isLocked());
assertTrue(lock.isHeldByCurrentThread());
awaitTermination(t);
releaseLock(lock);
}
/**
* Calling await without holding lock throws IllegalMonitorStateException
*/
public void testAwait_IMSE() { testAwait_IMSE(false); }
public void testAwait_IMSE_fair() { testAwait_IMSE(true); }
public void testAwait_IMSE(boolean fair) {
final ReentrantLock lock = new ReentrantLock(fair);
final Condition c = lock.newCondition();
for (AwaitMethod awaitMethod : AwaitMethod.values()) {
long startTime = System.nanoTime();
try {
await(c, awaitMethod);
shouldThrow();
} catch (IllegalMonitorStateException success) {
} catch (InterruptedException e) { threadUnexpectedException(e); }
assertTrue(millisElapsedSince(startTime) < LONG_DELAY_MS);
}
}
/**
* Calling signal without holding lock throws IllegalMonitorStateException
*/
public void testSignal_IMSE() { testSignal_IMSE(false); }
public void testSignal_IMSE_fair() { testSignal_IMSE(true); }
public void testSignal_IMSE(boolean fair) {
final ReentrantLock lock = new ReentrantLock(fair);
final Condition c = lock.newCondition();
try {
c.signal();
shouldThrow();
} catch (IllegalMonitorStateException success) {}
}
/**
* awaitNanos without a signal times out
*/
public void testAwaitNanos_Timeout() { testAwaitNanos_Timeout(false); }
public void testAwaitNanos_Timeout_fair() { testAwaitNanos_Timeout(true); }
public void testAwaitNanos_Timeout(boolean fair) {
try {
final ReentrantLock lock = new ReentrantLock(fair);
final Condition c = lock.newCondition();
lock.lock();
long startTime = System.nanoTime();
long timeoutMillis = 10;
long timeoutNanos = MILLISECONDS.toNanos(timeoutMillis);
long nanosRemaining = c.awaitNanos(timeoutNanos);
assertTrue(nanosRemaining <= 0);
assertTrue(millisElapsedSince(startTime) >= timeoutMillis);
lock.unlock();
} catch (InterruptedException fail) { threadUnexpectedException(fail); }
}
/**
* timed await without a signal times out
*/
public void testAwait_Timeout() { testAwait_Timeout(false); }
public void testAwait_Timeout_fair() { testAwait_Timeout(true); }
public void testAwait_Timeout(boolean fair) {
try {
final ReentrantLock lock = new ReentrantLock(fair);
final Condition c = lock.newCondition();
lock.lock();
long startTime = System.nanoTime();
long timeoutMillis = 10;
assertFalse(c.await(timeoutMillis, MILLISECONDS));
assertTrue(millisElapsedSince(startTime) >= timeoutMillis);
lock.unlock();
} catch (InterruptedException fail) { threadUnexpectedException(fail); }
}
/**
* awaitUntil without a signal times out
*/
public void testAwaitUntil_Timeout() { testAwaitUntil_Timeout(false); }
public void testAwaitUntil_Timeout_fair() { testAwaitUntil_Timeout(true); }
public void testAwaitUntil_Timeout(boolean fair) {
try {
final ReentrantLock lock = new ReentrantLock(fair);
final Condition c = lock.newCondition();
lock.lock();
// We shouldn't assume that nanoTime and currentTimeMillis
// use the same time source, so don't use nanoTime here.
java.util.Date delayedDate = delayedDate(timeoutMillis());
assertFalse(c.awaitUntil(delayedDate));
assertTrue(new java.util.Date().getTime() >= delayedDate.getTime());
lock.unlock();
} catch (InterruptedException fail) { threadUnexpectedException(fail); }
}
/**
* await returns when signalled
*/
public void testAwait() { testAwait(false); }
public void testAwait_fair() { testAwait(true); }
public void testAwait(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
final Condition c = lock.newCondition();
final CountDownLatch locked = new CountDownLatch(1);
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
lock.lock();
locked.countDown();
c.await();
lock.unlock();
}});
await(locked);
lock.lock();
assertHasWaiters(lock, c, t);
c.signal();
assertHasNoWaiters(lock, c);
assertTrue(t.isAlive());
lock.unlock();
awaitTermination(t);
}
/**
* hasWaiters throws NPE if null
*/
public void testHasWaitersNPE() { testHasWaitersNPE(false); }
public void testHasWaitersNPE_fair() { testHasWaitersNPE(true); }
public void testHasWaitersNPE(boolean fair) {
final ReentrantLock lock = new ReentrantLock(fair);
try {
lock.hasWaiters(null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* getWaitQueueLength throws NPE if null
*/
public void testGetWaitQueueLengthNPE() { testGetWaitQueueLengthNPE(false); }
public void testGetWaitQueueLengthNPE_fair() { testGetWaitQueueLengthNPE(true); }
public void testGetWaitQueueLengthNPE(boolean fair) {
final ReentrantLock lock = new ReentrantLock(fair);
try {
lock.getWaitQueueLength(null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* getWaitingThreads throws NPE if null
*/
public void testGetWaitingThreadsNPE() { testGetWaitingThreadsNPE(false); }
public void testGetWaitingThreadsNPE_fair() { testGetWaitingThreadsNPE(true); }
public void testGetWaitingThreadsNPE(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
try {
lock.getWaitingThreads(null);
shouldThrow();
} catch (NullPointerException success) {}
}
/**
* hasWaiters throws IllegalArgumentException if not owned
*/
public void testHasWaitersIAE() { testHasWaitersIAE(false); }
public void testHasWaitersIAE_fair() { testHasWaitersIAE(true); }
public void testHasWaitersIAE(boolean fair) {
final ReentrantLock lock = new ReentrantLock(fair);
final Condition c = lock.newCondition();
final ReentrantLock lock2 = new ReentrantLock(fair);
try {
lock2.hasWaiters(c);
shouldThrow();
} catch (IllegalArgumentException success) {}
}
/**
* hasWaiters throws IllegalMonitorStateException if not locked
*/
public void testHasWaitersIMSE() { testHasWaitersIMSE(false); }
public void testHasWaitersIMSE_fair() { testHasWaitersIMSE(true); }
public void testHasWaitersIMSE(boolean fair) {
final ReentrantLock lock = new ReentrantLock(fair);
final Condition c = lock.newCondition();
try {
lock.hasWaiters(c);
shouldThrow();
} catch (IllegalMonitorStateException success) {}
}
/**
* getWaitQueueLength throws IllegalArgumentException if not owned
*/
public void testGetWaitQueueLengthIAE() { testGetWaitQueueLengthIAE(false); }
public void testGetWaitQueueLengthIAE_fair() { testGetWaitQueueLengthIAE(true); }
public void testGetWaitQueueLengthIAE(boolean fair) {
final ReentrantLock lock = new ReentrantLock(fair);
final Condition c = lock.newCondition();
final ReentrantLock lock2 = new ReentrantLock(fair);
try {
lock2.getWaitQueueLength(c);
shouldThrow();
} catch (IllegalArgumentException success) {}
}
/**
* getWaitQueueLength throws IllegalMonitorStateException if not locked
*/
public void testGetWaitQueueLengthIMSE() { testGetWaitQueueLengthIMSE(false); }
public void testGetWaitQueueLengthIMSE_fair() { testGetWaitQueueLengthIMSE(true); }
public void testGetWaitQueueLengthIMSE(boolean fair) {
final ReentrantLock lock = new ReentrantLock(fair);
final Condition c = lock.newCondition();
try {
lock.getWaitQueueLength(c);
shouldThrow();
} catch (IllegalMonitorStateException success) {}
}
/**
* getWaitingThreads throws IllegalArgumentException if not owned
*/
public void testGetWaitingThreadsIAE() { testGetWaitingThreadsIAE(false); }
public void testGetWaitingThreadsIAE_fair() { testGetWaitingThreadsIAE(true); }
public void testGetWaitingThreadsIAE(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
final Condition c = lock.newCondition();
final PublicReentrantLock lock2 = new PublicReentrantLock(fair);
try {
lock2.getWaitingThreads(c);
shouldThrow();
} catch (IllegalArgumentException success) {}
}
/**
* getWaitingThreads throws IllegalMonitorStateException if not locked
*/
public void testGetWaitingThreadsIMSE() { testGetWaitingThreadsIMSE(false); }
public void testGetWaitingThreadsIMSE_fair() { testGetWaitingThreadsIMSE(true); }
public void testGetWaitingThreadsIMSE(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
final Condition c = lock.newCondition();
try {
lock.getWaitingThreads(c);
shouldThrow();
} catch (IllegalMonitorStateException success) {}
}
/**
* hasWaiters returns true when a thread is waiting, else false
*/
public void testHasWaiters() { testHasWaiters(false); }
public void testHasWaiters_fair() { testHasWaiters(true); }
public void testHasWaiters(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
final Condition c = lock.newCondition();
final CountDownLatch pleaseSignal = new CountDownLatch(1);
Thread t = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
lock.lock();
assertHasNoWaiters(lock, c);
assertFalse(lock.hasWaiters(c));
pleaseSignal.countDown();
c.await();
assertHasNoWaiters(lock, c);
assertFalse(lock.hasWaiters(c));
lock.unlock();
}});
await(pleaseSignal);
lock.lock();
assertHasWaiters(lock, c, t);
assertTrue(lock.hasWaiters(c));
c.signal();
assertHasNoWaiters(lock, c);
assertFalse(lock.hasWaiters(c));
lock.unlock();
awaitTermination(t);
assertHasNoWaiters(lock, c);
}
/**
* getWaitQueueLength returns number of waiting threads
*/
public void testGetWaitQueueLength() { testGetWaitQueueLength(false); }
public void testGetWaitQueueLength_fair() { testGetWaitQueueLength(true); }
public void testGetWaitQueueLength(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
final Condition c = lock.newCondition();
final CountDownLatch locked1 = new CountDownLatch(1);
final CountDownLatch locked2 = new CountDownLatch(1);
Thread t1 = new Thread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
lock.lock();
assertFalse(lock.hasWaiters(c));
assertEquals(0, lock.getWaitQueueLength(c));
locked1.countDown();
c.await();
lock.unlock();
}});
Thread t2 = new Thread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
lock.lock();
assertTrue(lock.hasWaiters(c));
assertEquals(1, lock.getWaitQueueLength(c));
locked2.countDown();
c.await();
lock.unlock();
}});
lock.lock();
assertEquals(0, lock.getWaitQueueLength(c));
lock.unlock();
t1.start();
await(locked1);
lock.lock();
assertHasWaiters(lock, c, t1);
assertEquals(1, lock.getWaitQueueLength(c));
lock.unlock();
t2.start();
await(locked2);
lock.lock();
assertHasWaiters(lock, c, t1, t2);
assertEquals(2, lock.getWaitQueueLength(c));
c.signalAll();
assertHasNoWaiters(lock, c);
lock.unlock();
awaitTermination(t1);
awaitTermination(t2);
assertHasNoWaiters(lock, c);
}
/**
* getWaitingThreads returns only and all waiting threads
*/
public void testGetWaitingThreads() { testGetWaitingThreads(false); }
public void testGetWaitingThreads_fair() { testGetWaitingThreads(true); }
public void testGetWaitingThreads(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
final Condition c = lock.newCondition();
final CountDownLatch locked1 = new CountDownLatch(1);
final CountDownLatch locked2 = new CountDownLatch(1);
Thread t1 = new Thread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
lock.lock();
assertTrue(lock.getWaitingThreads(c).isEmpty());
locked1.countDown();
c.await();
lock.unlock();
}});
Thread t2 = new Thread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
lock.lock();
assertFalse(lock.getWaitingThreads(c).isEmpty());
locked2.countDown();
c.await();
lock.unlock();
}});
lock.lock();
assertTrue(lock.getWaitingThreads(c).isEmpty());
lock.unlock();
t1.start();
await(locked1);
lock.lock();
assertHasWaiters(lock, c, t1);
assertTrue(lock.getWaitingThreads(c).contains(t1));
assertFalse(lock.getWaitingThreads(c).contains(t2));
assertEquals(1, lock.getWaitingThreads(c).size());
lock.unlock();
t2.start();
await(locked2);
lock.lock();
assertHasWaiters(lock, c, t1, t2);
assertTrue(lock.getWaitingThreads(c).contains(t1));
assertTrue(lock.getWaitingThreads(c).contains(t2));
assertEquals(2, lock.getWaitingThreads(c).size());
c.signalAll();
assertHasNoWaiters(lock, c);
lock.unlock();
awaitTermination(t1);
awaitTermination(t2);
assertHasNoWaiters(lock, c);
}
/**
* awaitUninterruptibly is uninterruptible
*/
public void testAwaitUninterruptibly() { testAwaitUninterruptibly(false); }
public void testAwaitUninterruptibly_fair() { testAwaitUninterruptibly(true); }
public void testAwaitUninterruptibly(boolean fair) {
final ReentrantLock lock = new ReentrantLock(fair);
final Condition c = lock.newCondition();
final CountDownLatch pleaseInterrupt = new CountDownLatch(2);
Thread t1 = newStartedThread(new CheckedRunnable() {
public void realRun() {
// Interrupt before awaitUninterruptibly
lock.lock();
pleaseInterrupt.countDown();
Thread.currentThread().interrupt();
c.awaitUninterruptibly();
assertTrue(Thread.interrupted());
lock.unlock();
}});
Thread t2 = newStartedThread(new CheckedRunnable() {
public void realRun() {
// Interrupt during awaitUninterruptibly
lock.lock();
pleaseInterrupt.countDown();
c.awaitUninterruptibly();
assertTrue(Thread.interrupted());
lock.unlock();
}});
await(pleaseInterrupt);
lock.lock();
lock.unlock();
t2.interrupt();
assertThreadStaysAlive(t1);
assertTrue(t2.isAlive());
lock.lock();
c.signalAll();
lock.unlock();
awaitTermination(t1);
awaitTermination(t2);
}
/**
* await/awaitNanos/awaitUntil is interruptible
*/
public void testInterruptible_await() { testInterruptible(false, AwaitMethod.await); }
public void testInterruptible_await_fair() { testInterruptible(true, AwaitMethod.await); }
public void testInterruptible_awaitTimed() { testInterruptible(false, AwaitMethod.awaitTimed); }
public void testInterruptible_awaitTimed_fair() { testInterruptible(true, AwaitMethod.awaitTimed); }
public void testInterruptible_awaitNanos() { testInterruptible(false, AwaitMethod.awaitNanos); }
public void testInterruptible_awaitNanos_fair() { testInterruptible(true, AwaitMethod.awaitNanos); }
public void testInterruptible_awaitUntil() { testInterruptible(false, AwaitMethod.awaitUntil); }
public void testInterruptible_awaitUntil_fair() { testInterruptible(true, AwaitMethod.awaitUntil); }
public void testInterruptible(boolean fair, final AwaitMethod awaitMethod) {
final PublicReentrantLock lock =
new PublicReentrantLock(fair);
final Condition c = lock.newCondition();
final CountDownLatch pleaseInterrupt = new CountDownLatch(1);
Thread t = newStartedThread(new CheckedInterruptedRunnable() {
public void realRun() throws InterruptedException {
lock.lock();
assertLockedByMoi(lock);
assertHasNoWaiters(lock, c);
pleaseInterrupt.countDown();
try {
await(c, awaitMethod);
} finally {
assertLockedByMoi(lock);
assertHasNoWaiters(lock, c);
lock.unlock();
assertFalse(Thread.interrupted());
}
}});
await(pleaseInterrupt);
assertHasWaiters(lock, c, t);
t.interrupt();
awaitTermination(t);
assertNotLocked(lock);
}
/**
* signalAll wakes up all threads
*/
public void testSignalAll_await() { testSignalAll(false, AwaitMethod.await); }
public void testSignalAll_await_fair() { testSignalAll(true, AwaitMethod.await); }
public void testSignalAll_awaitTimed() { testSignalAll(false, AwaitMethod.awaitTimed); }
public void testSignalAll_awaitTimed_fair() { testSignalAll(true, AwaitMethod.awaitTimed); }
public void testSignalAll_awaitNanos() { testSignalAll(false, AwaitMethod.awaitNanos); }
public void testSignalAll_awaitNanos_fair() { testSignalAll(true, AwaitMethod.awaitNanos); }
public void testSignalAll_awaitUntil() { testSignalAll(false, AwaitMethod.awaitUntil); }
public void testSignalAll_awaitUntil_fair() { testSignalAll(true, AwaitMethod.awaitUntil); }
public void testSignalAll(boolean fair, final AwaitMethod awaitMethod) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
final Condition c = lock.newCondition();
final CountDownLatch pleaseSignal = new CountDownLatch(2);
class Awaiter extends CheckedRunnable {
public void realRun() throws InterruptedException {
lock.lock();
pleaseSignal.countDown();
await(c, awaitMethod);
lock.unlock();
}
}
Thread t1 = newStartedThread(new Awaiter());
Thread t2 = newStartedThread(new Awaiter());
await(pleaseSignal);
lock.lock();
assertHasWaiters(lock, c, t1, t2);
c.signalAll();
assertHasNoWaiters(lock, c);
lock.unlock();
awaitTermination(t1);
awaitTermination(t2);
}
/**
* signal wakes up waiting threads in FIFO order
*/
public void testSignalWakesFifo() { testSignalWakesFifo(false); }
public void testSignalWakesFifo_fair() { testSignalWakesFifo(true); }
public void testSignalWakesFifo(boolean fair) {
final PublicReentrantLock lock =
new PublicReentrantLock(fair);
final Condition c = lock.newCondition();
final CountDownLatch locked1 = new CountDownLatch(1);
final CountDownLatch locked2 = new CountDownLatch(1);
Thread t1 = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
lock.lock();
locked1.countDown();
c.await();
lock.unlock();
}});
await(locked1);
Thread t2 = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
lock.lock();
locked2.countDown();
c.await();
lock.unlock();
}});
await(locked2);
lock.lock();
assertHasWaiters(lock, c, t1, t2);
assertFalse(lock.hasQueuedThreads());
c.signal();
assertHasWaiters(lock, c, t2);
assertTrue(lock.hasQueuedThread(t1));
assertFalse(lock.hasQueuedThread(t2));
c.signal();
assertHasNoWaiters(lock, c);
assertTrue(lock.hasQueuedThread(t1));
assertTrue(lock.hasQueuedThread(t2));
lock.unlock();
awaitTermination(t1);
awaitTermination(t2);
}
/**
* await after multiple reentrant locking preserves lock count
*/
public void testAwaitLockCount() { testAwaitLockCount(false); }
public void testAwaitLockCount_fair() { testAwaitLockCount(true); }
public void testAwaitLockCount(boolean fair) {
final PublicReentrantLock lock = new PublicReentrantLock(fair);
final Condition c = lock.newCondition();
final CountDownLatch pleaseSignal = new CountDownLatch(2);
Thread t1 = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
lock.lock();
assertLockedByMoi(lock);
assertEquals(1, lock.getHoldCount());
pleaseSignal.countDown();
c.await();
assertLockedByMoi(lock);
assertEquals(1, lock.getHoldCount());
lock.unlock();
}});
Thread t2 = newStartedThread(new CheckedRunnable() {
public void realRun() throws InterruptedException {
lock.lock();
lock.lock();
assertLockedByMoi(lock);
assertEquals(2, lock.getHoldCount());
pleaseSignal.countDown();
c.await();
assertLockedByMoi(lock);
assertEquals(2, lock.getHoldCount());
lock.unlock();
lock.unlock();
}});
await(pleaseSignal);
lock.lock();
assertHasWaiters(lock, c, t1, t2);
assertEquals(1, lock.getHoldCount());
c.signalAll();
assertHasNoWaiters(lock, c);
lock.unlock();
awaitTermination(t1);
awaitTermination(t2);
}
/**
* A serialized lock deserializes as unlocked
*/
public void testSerialization() { testSerialization(false); }
public void testSerialization_fair() { testSerialization(true); }
public void testSerialization(boolean fair) {
ReentrantLock lock = new ReentrantLock(fair);
lock.lock();
ReentrantLock clone = serialClone(lock);
assertEquals(lock.isFair(), clone.isFair());
assertTrue(lock.isLocked());
assertFalse(clone.isLocked());
assertEquals(1, lock.getHoldCount());
assertEquals(0, clone.getHoldCount());
clone.lock();
clone.lock();
assertTrue(clone.isLocked());
assertEquals(2, clone.getHoldCount());
assertEquals(1, lock.getHoldCount());
clone.unlock();
clone.unlock();
assertTrue(lock.isLocked());
assertFalse(clone.isLocked());
}
/**
* toString indicates current lock state
*/
public void testToString() { testToString(false); }
public void testToString_fair() { testToString(true); }
public void testToString(boolean fair) {
ReentrantLock lock = new ReentrantLock(fair);
assertTrue(lock.toString().contains("Unlocked"));
lock.lock();
assertTrue(lock.toString().contains("Locked"));
lock.unlock();
assertTrue(lock.toString().contains("Unlocked"));
}
}