001 /** 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017 package org.apache.camel.component.seda; 018 019 import java.util.concurrent.BlockingQueue; 020 import java.util.concurrent.CountDownLatch; 021 022 import org.apache.camel.Exchange; 023 import org.apache.camel.WaitForTaskToComplete; 024 import org.apache.camel.impl.SynchronizationAdapter; 025 import org.apache.camel.util.ExchangeHelper; 026 027 /** 028 * @version $Revision: 780267 $ 029 */ 030 public class SedaProducer extends CollectionProducer { 031 private final SedaEndpoint endpoint; 032 private final WaitForTaskToComplete waitForTaskToComplete; 033 034 public SedaProducer(SedaEndpoint endpoint, BlockingQueue<Exchange> queue, WaitForTaskToComplete waitForTaskToComplete) { 035 super(endpoint, queue); 036 this.endpoint = endpoint; 037 this.waitForTaskToComplete = waitForTaskToComplete; 038 } 039 040 @Override 041 public void process(final Exchange exchange) throws Exception { 042 // use a new copy of the exchange to route async and handover the on completion to the new copy 043 // so its the new copy that performs the on completion callback when its done 044 Exchange copy = exchange.newCopy(true); 045 // set a new from endpoint to be the seda queue 046 copy.setFromEndpoint(endpoint); 047 048 WaitForTaskToComplete wait = waitForTaskToComplete; 049 if (exchange.getIn().getHeader(Exchange.ASYNC_WAIT) != null) { 050 wait = exchange.getIn().getHeader(Exchange.ASYNC_WAIT, WaitForTaskToComplete.class); 051 } 052 053 if (wait == WaitForTaskToComplete.Always 054 || (wait == WaitForTaskToComplete.IfReplyExpected && ExchangeHelper.isOutCapable(exchange))) { 055 056 // only check for if there is a consumer if its the seda endpoint where we exepect a consumer in the same 057 // camel context. If you use the vm component the consumer could be in another camel context. 058 // for seda we want to check that a consumer exists otherwise we end up waiting forever for the response. 059 if (endpoint.getEndpointUri().startsWith("seda") && endpoint.getConsumers().isEmpty()) { 060 throw new IllegalStateException("Cannot send to endpoint: " + endpoint.getEndpointUri() + " as no consumers is registered." 061 + " With no consumers we end up waiting forever for the reply, as there are no consumers to process our exchange: " + exchange); 062 } 063 064 // latch that waits until we are complete 065 final CountDownLatch latch = new CountDownLatch(1); 066 067 // we should wait for the reply so install a on completion so we know when its complete 068 copy.addOnCompletion(new SynchronizationAdapter() { 069 @Override 070 public void onDone(Exchange response) { 071 try { 072 ExchangeHelper.copyResults(exchange, response); 073 } finally { 074 // always ensure latch is triggered 075 latch.countDown(); 076 } 077 } 078 }); 079 080 queue.add(copy); 081 latch.await(); 082 } else { 083 // no wait, eg its a InOnly then just add to queue and return 084 queue.add(copy); 085 } 086 } 087 088 @Override 089 protected void doStart() throws Exception { 090 super.doStart(); 091 endpoint.onStarted(this); 092 } 093 094 @Override 095 protected void doStop() throws Exception { 096 endpoint.onStopped(this); 097 super.doStop(); 098 } 099 }