Source code

001package org.apache.archiva.admin.repository.proxyconnector;
002/*
003 * Licensed to the Apache Software Foundation (ASF) under one
004 * or more contributor license agreements.  See the NOTICE file
005 * distributed with this work for additional information
006 * regarding copyright ownership.  The ASF licenses this file
007 * to you under the Apache License, Version 2.0 (the
008 * "License"); you may not use this file except in compliance
009 * with the License.  You may obtain a copy of the License at
010 *
011 *   http://www.apache.org/licenses/LICENSE-2.0
012 *
013 * Unless required by applicable law or agreed to in writing,
014 * software distributed under the License is distributed on an
015 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
016 * KIND, either express or implied.  See the License for the
017 * specific language governing permissions and limitations
018 * under the License.
019 */
020
021import org.apache.archiva.admin.model.beans.ProxyConnector;
022
023import java.util.Comparator;
024
025/**
026 * @author Olivier Lamy
027 * @since 1.4-M3
028 */
029public class ProxyConnectorOrderComparator
030    implements Comparator<ProxyConnector>
031{
032    private static ProxyConnectorOrderComparator INSTANCE = new ProxyConnectorOrderComparator();
033
034    @Override
035    public int compare( ProxyConnector o1, ProxyConnector o2 )
036    {
037        if ( o1 == null && o2 == null )
038        {
039            return 0;
040        }
041
042        // Ensure null goes to end of list.
043        if ( o1 == null && o2 != null )
044        {
045            return 1;
046        }
047
048        if ( o1 != null && o2 == null )
049        {
050            return -1;
051        }
052
053        // Ensure 0 (unordered) goes to end of list.
054        if ( o1.getOrder() == 0 && o2.getOrder() != 0 )
055        {
056            return 1;
057        }
058
059        if ( o1.getOrder() != 0 && o2.getOrder() == 0 )
060        {
061            return -1;
062        }
063
064        return o1.getOrder() - o2.getOrder();
065    }
066
067    public static ProxyConnectorOrderComparator getInstance()
068    {
069        return INSTANCE;
070    }
071}