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.util; 018 019import java.util.Comparator; 020import java.util.List; 021 022import org.apache.camel.Exchange; 023import org.apache.camel.Expression; 024 025/** 026 * An implementation of {@link java.util.Comparator} which takes a list of 027 * {@link org.apache.camel.Expression} objects which is evaluated 028 * on each exchange to compare them 029 * 030 * @version 031 */ 032public class ExpressionListComparator implements Comparator<Exchange> { 033 private final List<Expression> expressions; 034 035 public ExpressionListComparator(List<Expression> expressions) { 036 this.expressions = expressions; 037 } 038 039 public int compare(Exchange e1, Exchange e2) { 040 for (Expression expression : expressions) { 041 Object o1 = expression.evaluate(e1, Object.class); 042 Object o2 = expression.evaluate(e2, Object.class); 043 int answer = ObjectHelper.compare(o1, o2); 044 if (answer != 0) { 045 return answer; 046 } 047 } 048 return 0; 049 } 050}