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 java.util.Collections;
020    import java.util.Comparator;
021    import java.util.List;
022    
023    import org.apache.camel.Exchange;
024    import org.apache.camel.Expression;
025    import org.apache.camel.Message;
026    import org.apache.camel.Processor;
027    import org.apache.camel.support.ServiceSupport;
028    
029    /**
030     * A processor that sorts the expression using a comparator
031     */
032    public class SortProcessor<T> extends ServiceSupport implements Processor {
033    
034        private final Expression expression;
035        private final Comparator<? super T> comparator;
036    
037        public SortProcessor(Expression expression, Comparator<? super T> comparator) {
038            this.expression = expression;
039            this.comparator = comparator;
040        }
041    
042        public void process(Exchange exchange) throws Exception {
043            Message in = exchange.getIn();
044    
045            @SuppressWarnings("unchecked")
046            List<T> list = expression.evaluate(exchange, List.class);
047            Collections.sort(list, comparator);
048    
049            if (exchange.getPattern().isOutCapable()) {
050                Message out = exchange.getOut();
051                out.copyFrom(in);
052                out.setBody(list);
053            } else {
054                in.setBody(list);
055            }
056        }
057    
058        public String toString() {
059            return "Sort[" + expression + "]";
060        }
061    
062        @Override
063        protected void doStart() throws Exception {
064            // noop
065        }
066    
067        @Override
068        protected void doStop() throws Exception {
069            // noop
070        }
071    }
072    
073