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.component.jms.requestor;
018    
019    import java.util.HashMap;
020    import java.util.Map;
021    
022    public class MessageSelectorProvider {
023        protected Map<String, String> correlationIds;
024        protected boolean dirty = true;
025        protected StringBuilder expression;
026    
027        public MessageSelectorProvider() {
028            correlationIds = new HashMap<String, String>();
029        }
030    
031        public synchronized void addCorrelationID(String id) {
032            correlationIds.put(id, id);
033            dirty = true;
034        }
035    
036        public synchronized void removeCorrelationID(String id) {
037            correlationIds.remove(id);
038            dirty = true;
039        }
040    
041        public synchronized String get() {
042            if (!dirty) {
043                return expression.toString();
044            }
045            expression = new StringBuilder("JMSCorrelationID='");
046            boolean first = true;
047            for (Map.Entry<String, String> entry : correlationIds.entrySet()) {
048                if (!first) {
049                    expression.append(" OR JMSCorrelationID='");
050                }
051                expression.append(entry.getValue()).append("'");
052                if (first) {
053                    first = false;
054                }
055            }
056            dirty = false;
057            return expression.toString();
058        }
059    }