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
024 /**
025 * Handles calling the UnitOfWork.done() method when processing of an exchange
026 * is complete.
027 */
028 public final class UnitOfWorkProcessor extends DelegateAsyncProcessor {
029
030 public UnitOfWorkProcessor(AsyncProcessor processor) {
031 super(processor);
032 }
033
034 public boolean process(final Exchange exchange, final AsyncCallback callback) {
035 if (exchange.getUnitOfWork() == null) {
036 // If there is no existing UoW, then we should start one and
037 // terminate it once processing is completed for the exchange.
038 exchange.setUnitOfWork(new DefaultUnitOfWork());
039 return processor.process(exchange, new AsyncCallback() {
040 public void done(boolean sync) {
041 // Order here matters. We need to complete the callbacks
042 // since they will likely update the exchange with
043 // some final results.
044 callback.done(sync);
045 exchange.getUnitOfWork().done(exchange);
046 exchange.setUnitOfWork(null);
047 }
048 });
049 } else {
050 // There was an existing UoW, so we should just pass through..
051 // so that the guy the initiated the UoW can terminate it.
052 return processor.process(exchange, callback);
053 }
054 }
055
056 }