question: protected boolean doStart ( ) { if ( ! _lifecycle . isActive ( ) ) { return false ; } if ( ! isEnable ( ) ) { return false ; } int startingCount = _startingCount . getAndIncrement ( ) ; int threadCount = _threadCount . get ( ) + startingCount ; if ( _threadMax < threadCount ) { _startingCount . decrementAndGet ( ) ; onThreadMax ( ) ; return false ; } else if ( isIdleTooLow ( startingCount ) ) { return true ; } else { _startingCount . decrementAndGet ( ) ; return false ; } }
target:  Checks if the launcher should start another thread.