Source code

001package org.apache.archiva.proxy;
002
003/*
004 * Licensed to the Apache Software Foundation (ASF) under one
005 * or more contributor license agreements.  See the NOTICE file
006 * distributed with this work for additional information
007 * regarding copyright ownership.  The ASF licenses this file
008 * to you under the Apache License, Version 2.0 (the
009 * "License"); you may not use this file except in compliance
010 * with the License.  You may obtain a copy of the License at
011 *
012 *  http://www.apache.org/licenses/LICENSE-2.0
013 *
014 * Unless required by applicable law or agreed to in writing,
015 * software distributed under the License is distributed on an
016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017 * KIND, either express or implied.  See the License for the
018 * specific language governing permissions and limitations
019 * under the License.
020 */
021
022import org.apache.archiva.proxy.model.ProxyConnector;
023
024import java.util.Comparator;
025
026/**
027 * ProxyConnectorOrderComparator 
028 *
029 *
030 */
031public class ProxyConnectorOrderComparator
032    implements Comparator<ProxyConnector>
033{
034    private static ProxyConnectorOrderComparator INSTANCE = new ProxyConnectorOrderComparator();
035
036    public static ProxyConnectorOrderComparator getInstance()
037    {
038        return INSTANCE;
039    }
040
041    @Override
042    public int compare( ProxyConnector o1, ProxyConnector o2 )
043    {
044        if ( o1 == null && o2 == null )
045        {
046            return 0;
047        }
048
049        // Ensure null goes to end of list.
050        if ( o1 == null && o2 != null )
051        {
052            return 1;
053        }
054
055        if ( o1 != null && o2 == null )
056        {
057            return -1;
058        }
059
060        // Ensure 0 (unordered) goes to end of list.
061        if ( o1.getOrder() == 0 && o2.getOrder() != 0 )
062        {
063            return 1;
064        }
065
066        if ( o1.getOrder() != 0 && o2.getOrder() == 0 )
067        {
068            return -1;
069        }
070
071        return o1.getOrder() - o2.getOrder();
072    }
073}