question: private void addWorkerFailed ( Worker w ) { final ReentrantLock mainLock = this . mainLock ; mainLock . lock ( ) ; try { if ( w != null ) workers . remove ( w ) ; decrementWorkerCount ( ) ; tryTerminate ( ) ; } finally { mainLock . unlock ( ) ; } }
target:  Rolls back the worker thread creation. - removes worker from workers, if present - decrements worker count - rechecks for termination, in case the existence of this worker was holding up termination