JBossDeveloper

Ok, lock()/unlock() similar to TransactionImpl was added, along with a helper SynchronizedTransactionLocal class (in the branch I'm working).

Thanks

Actually the locking needs to be smarter than the one in TransactionImp because we want to "lock" the ThreadLocal based on the active transaction, i.e. synchronize the threads inside the same tx only.

My implementation is a bit naive for the time being, due to the notifyAll().

I guess I need to look for an EDU.oswego equivalent.

...
 /**
 * Set to monitor which transactions are "locked"
 * with lock() and unlock().
 */
 private static final Set txLockSet = new HashSet();
...
 /**
 * Lock using the current transaction
 */
 public void lock()
 {
 lock(getTransaction());
 }

 /**
 * Lock using the provided transaction
 *
 * @param transaction
 */
 public void lock(Transaction transaction)
 {
 if (transaction == null)
 {
 throw new IllegalStateException("there is no transaction");
 }

 synchronized (txLockSet)
 {
 while (!txLockSet.add(transaction))
 {
 try
 {
 txLockSet.wait();
 }
 catch (InterruptedException ex)
 {
 // ignore
 }
 }
 // got the lock
 }
 }

 /**
 * Unlock using the current transaction
 */
 public void unlock()
 {
 unlock(getTransaction());
 }

 public void unlock(Transaction transaction)
 {
 if (transaction == null)
 {
 throw new IllegalStateException("there is no transaction");
 }

 synchronized (txLockSet)
 {
 if (!txLockSet.remove(transaction))
 {
 throw new IllegalStateException("Unlocking, but not locked");
 }
 // REVISE
 txLockSet.notifyAll();
 }
 }

Another thing, txLockSet shouldn't be static, since we protect the state of each particular TreadLocal per tx.

Thanks a lot for the hints!

Actually we make the same mistake in TransactionImpl :)

...
 try
 {
 // Wakeup happens when:
 // - notify() is called from unlock()
 // - notifyAll is called from instanceDone()
 wait();
 }
 catch (InterruptedException ex)
 {
 // ignore
 }
...