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.processor; 018 019 import org.apache.camel.AsyncCallback; 020 import org.apache.camel.AsyncProcessor; 021 import org.apache.camel.Exchange; 022 import org.apache.camel.impl.DefaultUnitOfWork; 023 import static org.apache.camel.util.ObjectHelper.wrapRuntimeCamelException; 024 025 /** 026 * Handles calling the UnitOfWork.done() method when processing of an exchange 027 * is complete. 028 */ 029 public final class UnitOfWorkProcessor extends DelegateAsyncProcessor { 030 031 public UnitOfWorkProcessor(AsyncProcessor processor) { 032 super(processor); 033 } 034 035 public boolean process(final Exchange exchange, final AsyncCallback callback) { 036 if (exchange.getUnitOfWork() == null) { 037 // If there is no existing UoW, then we should start one and 038 // terminate it once processing is completed for the exchange. 039 final DefaultUnitOfWork uow = new DefaultUnitOfWork(); 040 exchange.setUnitOfWork(uow); 041 try { 042 uow.start(); 043 } catch (Exception e) { 044 throw wrapRuntimeCamelException(e); 045 } 046 // return the process code where we do stop and cleanup 047 return processor.process(exchange, new AsyncCallback() { 048 public void done(boolean sync) { 049 // Order here matters. We need to complete the callbacks 050 // since they will likely update the exchange with 051 // some final results. 052 callback.done(sync); 053 exchange.getUnitOfWork().done(exchange); 054 try { 055 uow.stop(); 056 } catch (Exception e) { 057 throw wrapRuntimeCamelException(e); 058 } 059 exchange.setUnitOfWork(null); 060 } 061 }); 062 } else { 063 // There was an existing UoW, so we should just pass through.. 064 // so that the guy the initiated the UoW can terminate it. 065 return processor.process(exchange, callback); 066 } 067 } 068 069 }