1 /*
2 * #%L
3 * ServerUpdateCallback.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.util.List;
23
24 import com.allanbank.mongodb.bson.Document;
25 import com.allanbank.mongodb.client.callback.FutureReplyCallback;
26 import com.allanbank.mongodb.client.message.Reply;
27
28 /**
29 * ServerUpdateCallback provides a special callback update the server with the
30 * first document in the reply. This is useful with {@code ismaster} or
31 * {@code replSetGetStatus} commands.
32 *
33 * @api.no This class is <b>NOT</b> part of the drivers API. This class may be
34 * mutated in incompatible ways between any two releases of the driver.
35 * @copyright 2012-2014, Allanbank Consulting, Inc., All Rights Reserved
36 */
37 public class ServerUpdateCallback extends FutureReplyCallback {
38
39 /** The server to update the seconds behind for. */
40 private final Server myServer;
41
42 /**
43 * Creates a new ServerUpdateCallback.
44 *
45 * @param server
46 * The server we are tracking the latency for.
47 */
48 public ServerUpdateCallback(final Server server) {
49 super();
50 myServer = server;
51 }
52
53 /**
54 * {@inheritDoc}
55 * <p>
56 * Overridden to update the server's latency based on the round trip reply
57 * time.
58 * </p>
59 */
60 @Override
61 public void callback(final Reply result) {
62 if (myServer != null) {
63 update(result);
64 }
65
66 super.callback(result);
67 }
68
69 /**
70 * {@inheritDoc}
71 * <p>
72 * Overridden to mark the server as {@link Integer#MAX_VALUE} seconds behind
73 * the primary.
74 * </p>
75 */
76 @Override
77 public void exception(final Throwable error) {
78 if (myServer != null) {
79 myServer.requestFailed();
80 }
81
82 super.exception(error);
83 }
84
85 /**
86 * Updates the server with the first document from the reply.
87 *
88 * @param reply
89 * The reply.
90 */
91 private void update(final Reply reply) {
92 if (reply != null) {
93 final List<Document> replyDocs = reply.getResults();
94 if (replyDocs.size() >= 1) {
95 final Document doc = replyDocs.get(0);
96
97 myServer.update(doc);
98 }
99 }
100 }
101 }