Is CountDownLatch Thread-Safe ?

[Joe Fisher]

If Thread wants to getCount() and conditionally countDown(), does block need to be synchronized ? These methods are not sych'd according to java docs

Thanks.

[Henry Wong]

Yes and no.... Yes, the countdown latch is thread safe and can be used by multiple threads. But no, the value return from getCount() is only valid til right before it returns. If you need to have data consistency between methods, you need to synchronize externally. (And this is true whether the individual methods are synchronized or not)

Henry
[ May 19, 2005: Message edited by: Henry Wong ]