question: void notifyPendingReceivedCallback ( final MessageImpl message , Exception exception ) { if ( ! pendingReceives . isEmpty ( ) ) { CompletableFuture < Message > receivedFuture = pendingReceives . poll ( ) ; if ( exception == null ) { checkNotNull ( message , "received message can't be null" ) ; if ( receivedFuture != null ) { if ( conf . getReceiverQueueSize ( ) == 0 ) { receivedFuture . complete ( message ) ; } else { messageProcessed ( message ) ; listenerExecutor . execute ( null ) ; } } } else { listenerExecutor . execute ( null ) ; } } }
target:  Notify waiting asyncReceive request with the received message