question: public boolean offer ( E e , long timeout , TimeUnit unit ) throws InterruptedException { checkNotNull ( e ) ; long nanos = unit . toNanos ( timeout ) ; final ReentrantLock lock = this . lock ; lock . lockInterruptibly ( ) ; try { while ( count == items . length ) { if ( nanos <= 0 ) return false ; nanos = notFull . awaitNanos ( nanos ) ; } enqueue ( e ) ; return true ; } finally { lock . unlock ( ) ; } }
target:  Inserts the specified element at the tail of this queue, waiting up to the specified wait time for space to become available if the queue is full.