public static int processNotification(String queueArn, String remoteAddress) { int messageCount = 0; long ts1 = System.currentTimeMillis(); CMBControllerServlet.valueAccumulator.initializeAllCounters(); contextQueues.putIfAbsent(queueArn, new ConcurrentLinkedQueue<AsyncContext>()); ConcurrentLinkedQueue<AsyncContext> contextQueue = contextQueues.get(queueArn); AsyncContext asyncContext = contextQueue.poll(); if (asyncContext == null) { logger.debug( "event=no_pending_receive queue_arn=" + queueArn + " remote_address=" + remoteAddress); return messageCount; } if (asyncContext.getRequest() == null) { logger.info( "event=skipping_invalid_context queue_arn=" + queueArn + " remote_address=" + remoteAddress); return messageCount; } if (!(asyncContext.getRequest() instanceof CQSHttpServletRequest)) { logger.info( "event=skipping_invalid_request queue_arn=" + queueArn + " remote_address=" + remoteAddress); return messageCount; } CQSHttpServletRequest request = (CQSHttpServletRequest) asyncContext.getRequest(); // skip if request is already finished or outdated if (!request.isActive() || System.currentTimeMillis() - request.getRequestReceivedTimestamp() > request.getWaitTime()) { logger.info( "event=skipping_outdated_context queue_arn=" + queueArn + " remote_address=" + remoteAddress); return messageCount; } logger.debug( "event=notification_received queue_arn=" + queueArn + " remote_address=" + remoteAddress); try { CQSQueue queue = request.getQueue(); List<CQSMessage> messageList = PersistenceFactory.getCQSMessagePersistence() .receiveMessage(queue, request.getReceiveAttributes()); if (messageList.size() > 0) { messageCount = messageList.size(); List<String> receiptHandles = new ArrayList<String>(); for (CQSMessage message : messageList) { receiptHandles.add(message.getReceiptHandle()); } request.setReceiptHandles(receiptHandles); request.setAttribute("lp", "yy"); // found lp call with messages CQSMonitor.getInstance() .addNumberOfMessagesReturned(queue.getRelativeUrl(), messageList.size()); String out = CQSMessagePopulator.getReceiveMessageResponseAfterSerializing( messageList, request.getFilterAttributes(), request.getFilterMessageAttributes()); Action.writeResponse(out, (HttpServletResponse) asyncContext.getResponse()); long lp_ms = System.currentTimeMillis() - ts1; request.setAttribute("lp_ms", lp_ms); String cass_msString = String.valueOf( CQSControllerServlet.valueAccumulator.getCounter(AccumulatorName.CassandraTime)); request.setAttribute("cass_ms", cass_msString); request.setAttribute( "cass_num_rd", CQSControllerServlet.valueAccumulator.getCounter(AccumulatorName.CassandraRead)); request.setAttribute( "cass_num_wr", CQSControllerServlet.valueAccumulator.getCounter(AccumulatorName.CassandraWrite)); request.setAttribute( "redis_ms", CQSControllerServlet.valueAccumulator.getCounter(AccumulatorName.RedisTime)); request.setAttribute( "io_ms", CQSControllerServlet.valueAccumulator.getCounter(AccumulatorName.IOTime)); asyncContext.complete(); } else { // if there's longpoll time left, put back on queue if (request.getWaitTime() - System.currentTimeMillis() + request.getRequestReceivedTimestamp() > 0) { logger.info( "event=no_messages_found_for_longpoll_receive action=re_queueing time_left_ms=" + (request.getWaitTime() - System.currentTimeMillis() + request.getRequestReceivedTimestamp()) + " queue_arn=" + queueArn + " remote_address=" + remoteAddress); contextQueue.offer(asyncContext); } } } catch (Exception ex) { logger.error("event=longpoll_queue_error queue_arn=" + queueArn, ex); } finally { CMBControllerServlet.valueAccumulator.deleteAllCounters(); } return messageCount; }