1 /*
2 * Copyright 2002-2014 the original author or authors.
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 package org.springframework.web.socket.sockjs.frame;
18
19 import java.io.IOException;
20 import java.io.InputStream;
21
22 /**
23 * Encode and decode messages to and from a SockJS message frame,
24 * essentially an array of JSON-encoded messages. For example:
25 *
26 * <pre class="code">
27 * a["message1","message2"]
28 * </pre>
29 *
30 * @author Rossen Stoyanchev
31 * @since 4.0
32 */
33 public interface SockJsMessageCodec {
34
35 /**
36 * Encode the given messages as a SockJS message frame. Aside from applying standard
37 * JSON quoting to each message, there are some additional JSON Unicode escaping
38 * rules. See the "JSON Unicode Encoding" section of SockJS protocol (i.e. the
39 * protocol test suite).
40 * @param messages the messages to encode
41 * @return the content for a SockJS message frame (never {@code null})
42 */
43 String encode(String... messages);
44
45 /**
46 * Decode the given SockJS message frame.
47 * @param content the SockJS message frame
48 * @return an array of messages, or {@code null} if none
49 * @throws IOException if the content could not be parsed
50 */
51 String[] decode(String content) throws IOException;
52
53 /**
54 * Decode the given SockJS message frame.
55 * @param content the SockJS message frame
56 * @return an array of messages, or {@code null} if none
57 * @throws IOException if the content could not be parsed
58 */
59 String[] decodeInputStream(InputStream content) throws IOException;
60
61 }