1 /*
2 * #%L
3 * ServerLatencyComparator.java - mongodb-async-driver - Allanbank Consulting, Inc.
4 * %%
5 * Copyright (C) 2011 - 2014 Allanbank Consulting, Inc.
6 * %%
7 * Licensed under the Apache License, Version 2.0 (the "License");
8 * you may not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS,
15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 * #L%
19 */
20 package com.allanbank.mongodb.client.state;
21
22 import java.io.Serializable;
23 import java.util.Comparator;
24
25 /**
26 * Compares {@link Server}'s based on the latency of the servers.
27 *
28 * @api.no This class is <b>NOT</b> part of the drivers API. This class may be
29 * mutated in incompatible ways between any two releases of the driver.
30 * @copyright 2011-2013, Allanbank Consulting, Inc., All Rights Reserved
31 */
32 public class ServerLatencyComparator implements Comparator<Server>,
33 Serializable {
34
35 /** A singleton instance of the comparator. No need to multiple instances. */
36 public static final Comparator<Server> COMPARATOR = new ServerLatencyComparator();
37
38 /** Serialization version of the class. */
39 private static final long serialVersionUID = -7926757327660948536L;
40
41 /**
42 * Creates a new {@link ServerLatencyComparator}.
43 */
44 private ServerLatencyComparator() {
45 super();
46 }
47
48 /**
49 * {@inheritDoc}
50 * <p>
51 * Compares the servers based on their respective average latencies.
52 * </p>
53 *
54 * @see Comparator#compare
55 */
56 @Override
57 public int compare(final Server o1, final Server o2) {
58 return Double.compare(o1.getAverageLatency(), o2.getAverageLatency());
59 }
60
61 }