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.spi;
018    
019    import org.apache.camel.Exchange;
020    
021    /**
022     * An object representing the unit of work processing an {@link Exchange}
023     * which allows the use of {@link Synchronization} hooks. This object might map one-to-one with
024     * a transaction in JPA or Spring; or might not.
025     *
026     * @version $Revision: 45123 $
027     */
028    public interface UnitOfWork {
029    
030        /**
031         * Adds a synchronization hook
032         */
033        void addSynchronization(Synchronization synchronization);
034    
035        /**
036         * Removes a synchronization hook
037         */
038        void removeSynchronization(Synchronization synchronization);
039    
040        /**
041         * Invoked when this unit of work has been completed, whether it has failed or completed
042         */
043        void done(Exchange exchange);
044    
045        /**
046         * Returns the unique ID of this unit of work, lazily creating one if it does not yet have one
047         */
048        String getId();
049    }