@Test
  public void testParallelGatewaySender() throws Exception {
    getSystem();
    CacheCreation cache = new CacheCreation();
    DiskStoreFactory dsf = cache.createDiskStoreFactory();
    dsf.create("LNSender");

    GatewaySenderFactory gatewaySenderFactory = cache.createGatewaySenderFactory();
    gatewaySenderFactory.setParallel(true);
    gatewaySenderFactory.setDispatcherThreads(13);
    gatewaySenderFactory.setManualStart(true);
    gatewaySenderFactory.setSocketBufferSize(1234);
    gatewaySenderFactory.setSocketReadTimeout(1050);
    gatewaySenderFactory.setBatchConflationEnabled(false);
    gatewaySenderFactory.setBatchSize(88);
    gatewaySenderFactory.setBatchTimeInterval(9);
    gatewaySenderFactory.setPersistenceEnabled(true);
    gatewaySenderFactory.setDiskStoreName("LNSender");
    gatewaySenderFactory.setDiskSynchronous(true);
    gatewaySenderFactory.setMaximumQueueMemory(211);
    gatewaySenderFactory.setAlertThreshold(35);

    GatewayEventFilter myEventFilter1 = new MyGatewayEventFilter1();
    gatewaySenderFactory.addGatewayEventFilter(myEventFilter1);
    GatewayTransportFilter myStreamFilter1 = new MyGatewayTransportFilter1();
    gatewaySenderFactory.addGatewayTransportFilter(myStreamFilter1);
    GatewayTransportFilter myStreamFilter2 = new MyGatewayTransportFilter2();
    gatewaySenderFactory.addGatewayTransportFilter(myStreamFilter2);
    GatewaySender parallelGatewaySender = gatewaySenderFactory.create("LN", 2);

    testXml(cache);
    Cache c = getCache();
    assertNotNull(c);
    Set<GatewaySender> sendersOnCache = c.getGatewaySenders();
    for (GatewaySender sender : sendersOnCache) {
      assertEquals(true, sender.isParallel());
      validateGatewaySender(parallelGatewaySender, sender);
    }
  }
Added to test the scenario of defect #50600.
geode-wan/src/distributedTest/java/org/apache/geode/cache/CacheXml70GatewayDUnitTest.java