001    /**
002     *
003     * Licensed to the Apache Software Foundation (ASF) under one or more
004     * contributor license agreements.  See the NOTICE file distributed with
005     * this work for additional information regarding copyright ownership.
006     * The ASF licenses this file to You under the Apache License, Version 2.0
007     * (the "License"); you may not use this file except in compliance with
008     * the License.  You may obtain a copy of the License at
009     *
010     * http://www.apache.org/licenses/LICENSE-2.0
011     *
012     * Unless required by applicable law or agreed to in writing, software
013     * distributed under the License is distributed on an "AS IS" BASIS,
014     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     * See the License for the specific language governing permissions and
016     * limitations under the License.
017     */
018    package org.apache.camel.processor.idempotent;
019    
020    /**
021     * Access to a repository of Message IDs to implement the
022     * <a href="http://activemq.apache.org/camel/idempotent-consumer.html">Idempotent Consumer</a> pattern.
023     *
024     * @version $Revision: 1.1 $
025     */
026    public interface MessageIdRepository {
027    
028        /**
029         * Returns true if this messageId has been processed before
030         * otherwise this messageId is added to the repository and false is returned.
031         *
032         * @param messageId the String ID of the message
033         * @return true if the message has been processed succesfully before otherwise false
034         */
035        boolean contains(String messageId);
036    }