0N/A

0N/A

39N/Aimport java.io.*;

0N/Aimport java.util.*;

0N/Aimport java.util.concurrent.*;

0N/Aimport java.util.concurrent.locks.*;

0N/A

0N/Apublic class Count {

39N/A final Random rnd = new Random();

39N/A

39N/A void lock(Lock lock) {

39N/A try {

39N/A switch (rnd.nextInt(4)) {

39N/A case 0: lock.lock(); break;

39N/A case 1: lock.lockInterruptibly(); break;

39N/A case 2: check(lock.tryLock()); break;

39N/A case 3: check(lock.tryLock(45, TimeUnit.MINUTES)); break;

39N/A }

39N/A } catch (Throwable t) { unexpected(t); }

39N/A }

39N/A

39N/A void test(String[] args) throws Throwable {

39N/A for (boolean fair : new boolean[] { true, false })

39N/A for (boolean serialClone : new boolean[] { true, false }) {

39N/A testReentrantLocks(fair, serialClone);

39N/A testConcurrentReadLocks(fair, serialClone);

39N/A }

39N/A }

39N/A

39N/A void testConcurrentReadLocks(final boolean fair,

39N/A final boolean serialClone) throws Throwable {

39N/A final int nThreads = 10;

39N/A final CyclicBarrier barrier = new CyclicBarrier(nThreads);

39N/A final ExecutorService es = Executors.newFixedThreadPool(nThreads);

39N/A final ReentrantReadWriteLock rwl = serialClone ?

39N/A serialClone(new ReentrantReadWriteLock(fair)) :

39N/A new ReentrantReadWriteLock(fair);

39N/A for (int i = 0; i < nThreads; i++) {

39N/A es.submit(new Runnable() { public void run() {

39N/A try {

39N/A int n = 5;

39N/A for (int i = 0; i < n; i++) {

39N/A barrier.await();

39N/A equal(rwl.getReadHoldCount(), i);

39N/A equal(rwl.getWriteHoldCount(), 0);

39N/A check(! rwl.isWriteLocked());

39N/A equal(rwl.getReadLockCount(), nThreads * i);

39N/A barrier.await();

39N/A lock(rwl.readLock());

39N/A }

39N/A for (int i = 0; i < n; i++) {

39N/A rwl.readLock().unlock();

39N/A barrier.await();

39N/A equal(rwl.getReadHoldCount(), n-i-1);

39N/A equal(rwl.getReadLockCount(), nThreads*(n-i-1));

39N/A equal(rwl.getWriteHoldCount(), 0);

39N/A check(! rwl.isWriteLocked());

39N/A barrier.await();

39N/A }

39N/A THROWS(IllegalMonitorStateException.class,

39N/A new F(){void f(){rwl.readLock().unlock();}},

39N/A new F(){void f(){rwl.writeLock().unlock();}});

39N/A barrier.await();

39N/A } catch (Throwable t) { unexpected(t); }}});}

39N/A es.shutdown();

39N/A check(es.awaitTermination(10, TimeUnit.SECONDS));

39N/A }

39N/A

39N/A void testReentrantLocks(final boolean fair,

39N/A final boolean serialClone) throws Throwable {

39N/A final ReentrantLock rl = serialClone ?

39N/A serialClone(new ReentrantLock(fair)) :

39N/A new ReentrantLock(fair);

39N/A final ReentrantReadWriteLock rwl = serialClone ?

39N/A serialClone(new ReentrantReadWriteLock(fair)) :

39N/A new ReentrantReadWriteLock(fair);

0N/A final int depth = 10;

39N/A equal(rl.isFair(), fair);

39N/A equal(rwl.isFair(), fair);

0N/A check(! rl.isLocked());

0N/A check(! rwl.isWriteLocked());

0N/A check(! rl.isHeldByCurrentThread());

0N/A check(! rwl.isWriteLockedByCurrentThread());

0N/A check(! rwl.writeLock().isHeldByCurrentThread());

0N/A

0N/A for (int i = 0; i < depth; i++) {

0N/A equal(rl.getHoldCount(), i);

0N/A equal(rwl.getReadLockCount(), i);

0N/A equal(rwl.getReadHoldCount(), i);

0N/A equal(rwl.getWriteHoldCount(), i);

0N/A equal(rwl.writeLock().getHoldCount(), i);

39N/A equal(rl.isLocked(), i > 0);

39N/A equal(rwl.isWriteLocked(), i > 0);

39N/A lock(rl);

39N/A lock(rwl.writeLock());

39N/A lock(rwl.readLock());

0N/A }

0N/A

0N/A for (int i = depth; i > 0; i--) {

0N/A check(! rl.hasQueuedThreads());

0N/A check(! rwl.hasQueuedThreads());

0N/A check(! rl.hasQueuedThread(Thread.currentThread()));

0N/A check(! rwl.hasQueuedThread(Thread.currentThread()));

0N/A check(rl.isLocked());

0N/A check(rwl.isWriteLocked());

0N/A check(rl.isHeldByCurrentThread());

0N/A check(rwl.isWriteLockedByCurrentThread());

0N/A check(rwl.writeLock().isHeldByCurrentThread());

0N/A equal(rl.getQueueLength(), 0);

0N/A equal(rwl.getQueueLength(), 0);

0N/A equal(rwl.getReadLockCount(), i);

0N/A equal(rl.getHoldCount(), i);

0N/A equal(rwl.getReadHoldCount(), i);

0N/A equal(rwl.getWriteHoldCount(), i);

0N/A equal(rwl.writeLock().getHoldCount(), i);

0N/A rwl.readLock().unlock();

0N/A rwl.writeLock().unlock();

0N/A rl.unlock();

0N/A }

39N/A THROWS(IllegalMonitorStateException.class,

39N/A new F(){void f(){rl.unlock();}},

39N/A new F(){void f(){rwl.readLock().unlock();}},

39N/A new F(){void f(){rwl.writeLock().unlock();}});

0N/A }

0N/A

0N/A //--------------------- Infrastructure ---------------------------

39N/A volatile int passed = 0, failed = 0;

39N/A void pass() {passed++;}

39N/A void fail() {failed++; Thread.dumpStack();}

39N/A void fail(String msg) {System.err.println(msg); fail();}

39N/A void unexpected(Throwable t) {failed++; t.printStackTrace();}

39N/A void check(boolean cond) {if (cond) pass(); else fail();}

39N/A void equal(Object x, Object y) {

0N/A if (x == null ? y == null : x.equals(y)) pass();

0N/A else fail(x + " not equal to " + y);}

0N/A public static void main(String[] args) throws Throwable {

39N/A new Count().instanceMain(args);}

39N/A void instanceMain(String[] args) throws Throwable {

39N/A try {test(args);} catch (Throwable t) {unexpected(t);}

0N/A System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed);

0N/A if (failed > 0) throw new AssertionError("Some tests failed");}

39N/A abstract class F {abstract void f() throws Throwable;}

39N/A void THROWS(Class<? extends Throwable> k, F... fs) {

39N/A for (F f : fs)

39N/A try {f.f(); fail("Expected " + k.getName() + " not thrown");}

39N/A catch (Throwable t) {

39N/A if (k.isAssignableFrom(t.getClass())) pass();

39N/A else unexpected(t);}}

39N/A

39N/A static byte[] serializedForm(Object obj) {

39N/A try {

39N/A ByteArrayOutputStream baos = new ByteArrayOutputStream();

39N/A new ObjectOutputStream(baos).writeObject(obj);

39N/A return baos.toByteArray();

39N/A } catch (IOException e) { throw new RuntimeException(e); }}

39N/A static Object readObject(byte[] bytes)

39N/A throws IOException, ClassNotFoundException {

39N/A InputStream is = new ByteArrayInputStream(bytes);

39N/A return new ObjectInputStream(is).readObject();}

39N/A @SuppressWarnings("unchecked")

39N/A static <T> T serialClone(T obj) {

39N/A try { return (T) readObject(serializedForm(obj)); }

39N/A catch (Exception e) { throw new RuntimeException(e); }}

0N/A}