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.impl; 018 019 import java.util.concurrent.ScheduledExecutorService; 020 021 import org.apache.camel.Endpoint; 022 import org.apache.camel.Exchange; 023 import org.apache.camel.PollingConsumer; 024 import org.apache.camel.Processor; 025 import org.apache.camel.util.ServiceHelper; 026 027 /** 028 * A default implementation of an event driven {@link org.apache.camel.Consumer} which uses the 029 * {@link PollingConsumer} 030 * 031 * @version 032 */ 033 public class DefaultScheduledPollConsumer extends ScheduledPollConsumer { 034 private PollingConsumer pollingConsumer; 035 036 public DefaultScheduledPollConsumer(DefaultEndpoint defaultEndpoint, Processor processor) { 037 super(defaultEndpoint, processor); 038 } 039 040 public DefaultScheduledPollConsumer(Endpoint endpoint, Processor processor, ScheduledExecutorService executor) { 041 super(endpoint, processor, executor); 042 } 043 044 protected int poll() throws Exception { 045 int messagesPolled = 0; 046 047 while (isPollAllowed()) { 048 Exchange exchange = pollingConsumer.receiveNoWait(); 049 if (exchange == null) { 050 break; 051 } 052 053 messagesPolled++; 054 log.trace("Polled {} {}", messagesPolled, exchange); 055 056 // if the result of the polled exchange has output we should create a new exchange and 057 // use the output as input to the next processor 058 if (exchange.hasOut()) { 059 // lets create a new exchange 060 Exchange newExchange = getEndpoint().createExchange(); 061 newExchange.getIn().copyFrom(exchange.getOut()); 062 exchange = newExchange; 063 } 064 getProcessor().process(exchange); 065 } 066 067 return messagesPolled; 068 } 069 070 @Override 071 protected void doStart() throws Exception { 072 pollingConsumer = getEndpoint().createPollingConsumer(); 073 ServiceHelper.startService(pollingConsumer); 074 super.doStart(); 075 } 076 077 @Override 078 protected void doStop() throws Exception { 079 ServiceHelper.stopService(pollingConsumer); 080 super.doStop(); 081 } 082 }