001    /*--------------------------------------------------------------------------+
002    $Id: FormalParameterComparator.java 26283 2010-02-18 11:18:57Z juergens $
003    |                                                                          |
004    | Copyright 2005-2010 Technische Universitaet Muenchen                     |
005    |                                                                          |
006    | Licensed under the Apache License, Version 2.0 (the "License");          |
007    | you may not use this file except in compliance with the License.         |
008    | 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 edu.tum.cs.commons.reflect;
019    
020    import java.util.Comparator;
021    
022    /**
023     * This comparator orders formal parameters by their position within the formal
024     * parameter list of the defining method. This comparator raises an exception if
025     * the the compared parameters do not belong to the same method.
026     * 
027     * 
028     * @author Florian Deissenboeck
029     * @author $Author: juergens $
030     * @version $Rev: 26283 $
031     * @levd.rating GREEN Hash: 06C5FDF68F8F0EF99EE068876259CBC7
032     */
033    public class FormalParameterComparator implements Comparator<FormalParameter> {
034    
035        /**
036         * Compae formal parameters by their position within the formal parameter
037         * list of the defining method.
038         * 
039         * @throws IllegalArgumentException
040         *             if parameters belong to different methods.
041         */
042        public int compare(FormalParameter p1, FormalParameter p2)
043                throws IllegalArgumentException {
044            if (!p1.getMethod().equals(p2.getMethod())) {
045                throw new IllegalArgumentException(
046                        "Parameters must belong to same method");
047            }
048            return p1.getPosition() - p2.getPosition();
049        }
050    }