1 /*
2 * #%L
3 * ReplyCommandCallback.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
21 package com.allanbank.mongodb.client.callback;
22
23 import java.util.List;
24
25 import com.allanbank.mongodb.Callback;
26 import com.allanbank.mongodb.MongoDbException;
27 import com.allanbank.mongodb.bson.Document;
28 import com.allanbank.mongodb.bson.Element;
29 import com.allanbank.mongodb.client.message.Reply;
30 import com.allanbank.mongodb.error.ReplyException;
31
32 /**
33 * Callback to expect and extract a single document from the reply.
34 *
35 * @api.no This class is <b>NOT</b> part of the drivers API. This class may be
36 * mutated in incompatible ways between any two releases of the driver.
37 * @copyright 2011-2013, Allanbank Consulting, Inc., All Rights Reserved
38 */
39 public class ReplyCommandCallback extends AbstractReplyCallback<Document> {
40
41 /**
42 * Create a new ReplyDocumentCallback.
43 *
44 * @param results
45 * The callback to notify of the reply document.
46 */
47 public ReplyCommandCallback(final Callback<Document> results) {
48 super(results);
49 }
50
51 /**
52 * {@inheritDoc}
53 * <p>
54 * Creates an exception if the {@link Reply} has less than or more than a
55 * single reply document.
56 * </p>
57 *
58 * @param reply
59 * The raw reply.
60 * @return The exception created.
61 */
62 @Override
63 protected MongoDbException asError(final Reply reply) {
64 MongoDbException error = super.asError(reply);
65 if (error == null) {
66 final List<Document> results = reply.getResults();
67 if (results.size() != 1) {
68 error = new ReplyException(reply,
69 "Should only be a single document in the reply.");
70 }
71 }
72 return error;
73 }
74
75 /**
76 * {@inheritDoc}
77 * <p>
78 * Overridden to not throw an exception on a zero 'ok' value.
79 * </p>
80 *
81 * @param reply
82 * The raw reply.
83 * @param knownError
84 * If true then the reply is assumed to be an error reply.
85 * @return The exception created.
86 */
87 @Override
88 protected MongoDbException asError(final Reply reply,
89 final boolean knownError) {
90 final List<Document> results = reply.getResults();
91 if (results.size() == 1) {
92 final Document doc = results.get(0);
93 final Element okElem = doc.get("ok");
94 final Element errorNumberElem = doc.get("code");
95 Element errorMessageElem = null;
96 for (int i = 0; (errorMessageElem == null)
97 && (i < ERROR_MESSAGE_FIELDS.size()); ++i) {
98 errorMessageElem = doc.get(ERROR_MESSAGE_FIELDS.get(i));
99 }
100
101 if ((okElem == null) && knownError) {
102 return asError(reply, -1, toInt(errorNumberElem),
103 asString(errorMessageElem));
104
105 }
106 }
107 return null;
108 }
109
110 /**
111 * {@inheritDoc}
112 * <p>
113 * Overridden to return the reply document.
114 * </p>
115 *
116 * @see AbstractReplyCallback#convert(Reply)
117 */
118 @Override
119 protected Document convert(final Reply reply) throws MongoDbException {
120 final List<Document> results = reply.getResults();
121 if (results.size() == 1) {
122 return results.get(0);
123 }
124
125 return null;
126 }
127 }