question: protected void decrementTaskCount ( ) { taskCountLock . lock ( ) ; try { taskCount -- ; if ( taskCount == 0 ) { synchronized ( threadPool ) { threadPool . notify ( ) ; } } } catch ( Exception e ) { e . printStackTrace ( ) ; } finally { taskCountLock . unlock ( ) ; } }
target:  Decrements the number of running tasks. If this number is 0, the ThreadPool is notified.