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.AsyncCallback; 024 import org.apache.camel.AsyncProcessor; 025 import org.apache.camel.Exchange; 026 import org.apache.camel.Expression; 027 import org.apache.camel.Message; 028 import org.apache.camel.support.ServiceSupport; 029 import org.apache.camel.util.AsyncProcessorHelper; 030 031 /** 032 * A processor that sorts the expression using a comparator 033 */ 034 public class SortProcessor<T> extends ServiceSupport implements AsyncProcessor { 035 036 private final Expression expression; 037 private final Comparator<? super T> comparator; 038 039 public SortProcessor(Expression expression, Comparator<? super T> comparator) { 040 this.expression = expression; 041 this.comparator = comparator; 042 } 043 044 public void process(Exchange exchange) throws Exception { 045 AsyncProcessorHelper.process(this, exchange); 046 } 047 048 @Override 049 public boolean process(Exchange exchange, AsyncCallback callback) { 050 try { 051 Message in = exchange.getIn(); 052 053 @SuppressWarnings("unchecked") 054 List<T> list = expression.evaluate(exchange, List.class); 055 Collections.sort(list, comparator); 056 057 if (exchange.getPattern().isOutCapable()) { 058 Message out = exchange.getOut(); 059 out.copyFrom(in); 060 out.setBody(list); 061 } else { 062 in.setBody(list); 063 } 064 } catch (Exception e) { 065 exchange.setException(e); 066 } 067 068 callback.done(true); 069 return true; 070 } 071 072 public String toString() { 073 return "Sort[" + expression + "]"; 074 } 075 076 @Override 077 protected void doStart() throws Exception { 078 // noop 079 } 080 081 @Override 082 protected void doStop() throws Exception { 083 // noop 084 } 085 } 086 087