/**
* Tries to acquire write lock for a given transaction. If <CODE>this.writeCount</CODE> is greater
* than the currents tx's write count or the read count is greater than the currents tx's read
* count the transaction has to wait and the {@link RagManager#checkWaitOn} method is invoked for
* deadlock detection.
*
* <p>If the lock can be acquires the lock count is updated on <CODE>this</CODE> and the
* transaction lock element (tle).
*
* @throws DeadlockDetectedException if a deadlock is detected
*/
synchronized void acquireWriteLock(Object tx) throws DeadlockDetectedException {
TxLockElement tle = getOrCreateLockElement(tx);
try {
tle.movedOn = false;
boolean shouldAddWait = true;
Thread currentThread = currentThread();
while (totalWriteCount > tle.writeCount || totalReadCount > tle.readCount) {
ragManager.checkWaitOn(this, tx);
if (shouldAddWait) {
waitingThreadList.addFirst(new WaitElement(tle, WRITE, currentThread));
}
try {
wait();
shouldAddWait = false;
} catch (InterruptedException e) {
interrupted();
shouldAddWait = true;
}
ragManager.stopWaitOn(this, tx);
}
registerWriteLockAcquired(tx, tle);
} finally {
// if deadlocked, remove marking so lock is removed when empty
tle.movedOn = true;
marked--;
}
}
private void waitIndefinitely() {
while (true) {
try {
sleep(MAX_VALUE);
} catch (InterruptedException e) {
interrupted();
// meh
}
}
}
private void deadlockGuardedWait(
Object tx,
TxLockElement tle,
LockType lockType) { // given: we must be in a synchronized block here
ragManager.checkWaitOn(this, tx);
waitingThreadList.addFirst(new WaitElement(tle, lockType, currentThread()));
try {
wait();
} catch (InterruptedException e) {
interrupted();
}
ragManager.stopWaitOn(this, tx);
}
public void testNoOpServiceStartStopAndWaitUninterruptible() throws Exception {
NoOpService service = new NoOpService();
currentThread().interrupt();
try {
service.startAndWait();
assertEquals(State.RUNNING, service.state());
service.stopAndWait();
assertEquals(State.TERMINATED, service.state());
assertTrue(currentThread().isInterrupted());
} finally {
Thread.interrupted(); // clear interrupt for future tests
}
}
public int waitFor() throws InterruptedException {
waitForInterruptibly(handle);
if (Thread.interrupted()) throw new InterruptedException();
return exitValue();
}
