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 */
017package org.apache.camel.spi;
018
019import java.util.Set;
020
021import org.apache.camel.CamelContext;
022import org.apache.camel.Exchange;
023
024/**
025 * Access to a repository to store aggregated exchanges to support pluggable implementations.
026 *  
027 * @version 
028 */
029public interface AggregationRepository {
030
031    /**
032     * Add the given {@link Exchange} under the correlation key.
033     * <p/>
034     * Will replace any existing exchange.
035     * <p/>
036     * <b>Important:</b> This method is <b>not</b> invoked if only one exchange was completed, and therefore
037     * the exchange does not need to be added to a repository, as its completed immediately.
038     *
039     * @param camelContext   the current CamelContext
040     * @param key            the correlation key
041     * @param exchange       the aggregated exchange
042     * @return the old exchange if any existed
043     */
044    Exchange add(CamelContext camelContext, String key, Exchange exchange);
045
046    /**
047     * Gets the given exchange with the correlation key
048     * <p/>
049     * This method is always invoked for any incoming exchange in the aggregator.
050     *
051     * @param camelContext   the current CamelContext
052     * @param key            the correlation key
053     * @return the exchange, or <tt>null</tt> if no exchange was previously added
054     */
055    Exchange get(CamelContext camelContext, String key);
056
057    /**
058     * Removes the exchange with the given correlation key, which should happen
059     * when an {@link Exchange} is completed
060     * <p/>
061     * <b>Important:</b> This method is <b>not</b> invoked if only one exchange was completed, and therefore
062     * the exchange does not need to be added to a repository, as its completed immediately.
063     *
064     * @param camelContext   the current CamelContext
065     * @param key            the correlation key
066     * @param exchange       the exchange to remove
067     */
068    void remove(CamelContext camelContext, String key, Exchange exchange);
069
070    /**
071     * Confirms the completion of the {@link Exchange}.
072     * <p/>
073     * This method is always invoked.
074     *
075     * @param camelContext  the current CamelContext
076     * @param exchangeId    exchange id to confirm
077     */
078    void confirm(CamelContext camelContext, String exchangeId);
079
080    /**
081     * Gets the keys currently in the repository.
082     *
083     * @return the keys
084     */
085    Set<String> getKeys();
086
087}