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.Processor;
023    import org.apache.camel.spi.RouteContext;
024    
025    /**
026     * A processor that processes the processor in a {@link org.apache.camel.spi.SubUnitOfWork} context.
027     * <p/>
028     * This processor ensures the {@link org.apache.camel.spi.UnitOfWork#beginSubUnitOfWork(org.apache.camel.Exchange)}
029     * and {@link org.apache.camel.spi.UnitOfWork#endSubUnitOfWork(org.apache.camel.Exchange)} is executed.
030     *
031     * @see org.apache.camel.spi.SubUnitOfWork
032     * @see org.apache.camel.spi.SubUnitOfWorkCallback
033     */
034    public class SubUnitOfWorkProcessor extends UnitOfWorkProcessor {
035    
036        // See code comment in DefaultUnitOfWork for reasons why this implementation is named SubUnitOfWorkProcessor
037    
038        public SubUnitOfWorkProcessor(Processor processor) {
039            super(processor);
040        }
041    
042        public SubUnitOfWorkProcessor(AsyncProcessor processor) {
043            super(processor);
044        }
045    
046        public SubUnitOfWorkProcessor(RouteContext routeContext, Processor processor) {
047            super(routeContext, processor);
048        }
049    
050        public SubUnitOfWorkProcessor(RouteContext routeContext, AsyncProcessor processor) {
051            super(routeContext, processor);
052        }
053    
054        @Override
055        public boolean process(final Exchange exchange, final AsyncCallback callback) {
056            // begin savepoint
057            exchange.getUnitOfWork().beginSubUnitOfWork(exchange);
058            // process the exchange
059            return super.process(exchange, new AsyncCallback() {
060                @Override
061                public void done(boolean doneSync) {
062                    try {
063                        // end sub unit of work
064                        exchange.getUnitOfWork().endSubUnitOfWork(exchange);
065                    } finally {
066                        // must ensure callback is invoked
067                        callback.done(doneSync);
068                    }
069                }
070    
071                @Override
072                public String toString() {
073                    return "SubUnitOfWorkCallback";
074                }
075            });
076        }
077    
078        @Override
079        public String toString() {
080            return "SubUnitOfWorkProcessor[" + processor + "]";
081        }
082    }