001/*-------------------------------------------------------------------------+
002|                                                                          |
003| Copyright 2005-2011 The ConQAT Project                                   |
004|                                                                          |
005| Licensed under the Apache License, Version 2.0 (the "License");          |
006| you may not use this file except in compliance with the License.         |
007| 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.conqat.lib.commons.options;
018
019import java.util.Comparator;
020
021/**
022 * A comparator for ordering options in a way used for usage messages. Sorting
023 * is performed on the short name and then on the long name (if present). If the
024 * short name is missing, the long name is sorted into the short names.
025 * <p>
026 * Basically we just concatenate the short and long name and compare the
027 * resulting string.
028 *
029 * @author Benjamin Hummel
030 */
031public class AOptionComparator implements Comparator<Option> {
032
033        /** {@inheritDoc} */
034        @Override
035        public int compare(Option o1, Option o2) {
036                return concatenatedName(o1).compareTo(concatenatedName(o2));
037        }
038
039        /**
040         * Returns the concatenation of the short and the long name, omitting those
041         * parts missing.
042         *
043         * @param option
044         *            the option to take the names from.
045         * @return the concatenated names.
046         */
047        private static String concatenatedName(Option option) {
048                if (option.shortName() == 0) {
049                        return option.longName();
050                }
051                return option.shortName() + option.longName();
052        }
053}