private void scanRequest( Collection<Script> match, final TransactionListener listener, String requestQueue) throws BCSAPIException { try (ConnectorSession session = connection.createSession()) { ConnectorMessage m = session.createMessage(); ConnectorProducer exactMatchProducer = session.createProducer(session.createQueue(requestQueue)); BCSAPIMessage.ExactMatchRequest.Builder builder = BCSAPIMessage.ExactMatchRequest.newBuilder(); for (Script d : match) { builder.addMatch(ByteString.copyFrom(d.toByteArray())); } m.setPayload(builder.build().toByteArray()); final ConnectorTemporaryQueue answerQueue = session.createTemporaryQueue(); final ConnectorConsumer consumer = session.createConsumer(answerQueue); m.setReplyTo(answerQueue); final Semaphore ready = new Semaphore(0); consumer.setMessageListener( message -> { try { byte[] body = message.getPayload(); if (body != null) { APITransaction t = APITransaction.fromProtobuf(BCSAPIMessage.TX.parseFrom(body)); listener.process(t); } else { consumer.close(); answerQueue.delete(); ready.release(); } } catch (ConnectorException | HyperLedgerException | InvalidProtocolBufferException e) { log.error("Malformed message received for scan matching transactions", e); } }); exactMatchProducer.send(m); ready.acquireUninterruptibly(); } catch (ConnectorException e) { throw new BCSAPIException(e); } }