利用spring-websocket包搭建websocket服务

折腾了将近一天，终于搭建好websocket服务，中间遇到不少的坑，现在记录一下，也供他们参考少走弯路。

开发环境：<spring.version>4.2.5.RELEASE</spring.version>     Tomcat8   jdk8  maven

spring搭建websocket有两种方式：

1、利用javaee-api以注解的形式搭建，见上一篇博文《spring+tomcat8实现websocket 》

2、利用spring-websocket包搭建，本篇介绍的内容。

注意：这种方式必须注释掉这个，不然会冲突

<!-- <dependency>
            <groupId>javax</groupId>
            <artifactId>javaee-api</artifactId>
            <version>7.0</version>
        </dependency> -->

需要用到的spring包：

<dependency>  
           <groupId>org.springframework</groupId>  
           <artifactId>spring-websocket</artifactId>  
           <version>${spring.version}</version>  
        </dependency>  
        <dependency>  
           <groupId>org.springframework</groupId>  
           <artifactId>spring-messaging</artifactId>  
           <version>${spring.version}</version>  
        </dependency> 
其他辅助包：

<dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>${jackson-version}</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>${jackson-version}</version>
        </dependency>
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>${jackson-version}</version>
        </dependency>

Java代码：两个类  WebSocketConfig 和 SystemWebSocketHandler

[java] view plain copy

1. @Configuration  
2. @EnableWebMvc  
3. @EnableWebSocket  
4. public class WebSocketConfig extends WebMvcConfigurerAdapter implements WebSocketConfigurer{  
5.   
6.     @Override  
7.     public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {  
8.         registry.addHandler(systemWebSocketHandler(),"/webSocketServer");  
9.         registry.addHandler(systemWebSocketHandler(),"/webSocketServer/sockjs").setAllowedOrigins("*").withSockJS();  
10.          //registry.addHandler(systemWebSocketHandler(),"/webSocketServer").addInterceptors(new WebSocketHandshakeInterceptor());  
11.          //registry.addHandler(systemWebSocketHandler(), "/sockjs/webSocketServer").addInterceptors(new WebSocketHandshakeInterceptor()).withSockJS();  
12.          //registry.addHandler(systemWebSocketHandler(), "/webSocketServer/sockjs").withSockJS();  
13.          /*registry.addHandler(systemWebSocketHandler(),"/ws").addInterceptors(new WebSocketHandshakeInterceptor()); 
14.             registry.addHandler(systemWebSocketHandler(), "/ws/sockjs").addInterceptors(new WebSocketHandshakeInterceptor()) 
15.                     .withSockJS();*/  
16.     }  
17.       
18.     @Bean  
19.     public WebSocketHandler systemWebSocketHandler(){  
20.         return new SystemWebSocketHandler();  
21.     }  
22.       

[java] view plain copy

1. import java.io.IOException;  
2. import java.util.ArrayList;  
3. import java.util.Date;  
4.   
5. import org.slf4j.Logger;  
6. import org.slf4j.LoggerFactory;  
7. import org.springframework.messaging.Message;  
8. import org.springframework.web.socket.CloseStatus;  
9. import org.springframework.web.socket.TextMessage;  
10. import org.springframework.web.socket.WebSocketHandler;  
11. import org.springframework.web.socket.WebSocketMessage;  
12. import org.springframework.web.socket.WebSocketSession;  
13.   
14. import com.mspj.frame.core.web.controller.BaseWebControllerImpl;  
15.   
16. public class SystemWebSocketHandler implements WebSocketHandler {  
17.        
18.     private Logger log = LoggerFactory.getLogger(SystemWebSocketHandler.class);  
19.       
20.     private static final ArrayList<WebSocketSession> users = new ArrayList<WebSocketSession>();;  
21.    
22.    
23.     @Override  
24.     public void afterConnectionEstablished(WebSocketSession session) throws Exception {  
25.         System.out.println("ConnectionEstablished");  
26.         log.debug("ConnectionEstablished");  
27.         users.add(session);  
28.           
29.         session.sendMessage(new TextMessage("connect"));  
30.         session.sendMessage(new TextMessage("new_msg"));  
31.           
32.     }  
33.    
34.     @Override  
35.     public void handleMessage(WebSocketSession session, WebSocketMessage<?> message) throws Exception {  
36.         System.out.println("handleMessage" + message.toString());  
37.         log.debug("handleMessage" + message.toString());  
38.         //sendMessageToUsers();  
39.         session.sendMessage(new TextMessage(new Date() + ""));  
40.     }  
41.    
42.     @Override  
43.     public void handleTransportError(WebSocketSession session, Throwable exception) throws Exception {  
44.         if(session.isOpen()){  
45.             session.close();  
46.         }  
47.         users.remove(session);  
48.           
49.         log.debug("handleTransportError" + exception.getMessage());  
50.     }  
51.    
52.     @Override  
53.     public void afterConnectionClosed(WebSocketSession session, CloseStatus closeStatus) throws Exception {  
54.         users.remove(session);  
55.         log.debug("afterConnectionClosed" + closeStatus.getReason());  
56.           
57.     }  
58.    
59.     @Override  
60.     public boolean supportsPartialMessages() {  
61.         return false;  
62.     }  
63.    
64.     /** 
65.      * 给所有在线用户发送消息 
66.      * 
67.      * @param message 
68.      */  
69.     public void sendMessageToUsers(TextMessage message) {  
70.         for (WebSocketSession user : users) {  
71.             try {  
72.                 if (user.isOpen()) {  
73.                     user.sendMessage(message);  
74.                 }  
75.             } catch (IOException e) {  
76.                 e.printStackTrace();  
77.             }  
78.         }  
79.     }  
80.    
81. }  

前端调式页面代码

[html] view plain copy

1. <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">  
2. <html>  
3. <head>  
4. <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">  
5. <title>WebSocket/SockJS Echo Sample (Adapted from Tomcat's echo sample)</title>  
6.     <style type="text/css">  
7.         #connect-container {  
8.             float: left;  
9.             width: 400px  
10.         }  
11.   
12.         #connect-container div {  
13.             padding: 5px;  
14.         }  
15.   
16.         #console-container {  
17.             float: left;  
18.             margin-left: 15px;  
19.             width: 400px;  
20.         }  
21.   
22.         #console {  
23.             border: 1px solid #CCCCCC;  
24.             border-right-color: #999999;  
25.             border-bottom-color: #999999;  
26.             height: 170px;  
27.             overflow-y: scroll;  
28.             padding: 5px;  
29.             width: 100%;  
30.         }  
31.   
32.         #console p {  
33.             padding: 0;  
34.             margin: 0;  
35.         }  
36.     </style>  
37.   
38.     <script src="http://cdn.sockjs.org/sockjs-0.3.min.js"></script>  
39.   
40.     <script type="text/javascript">  
41.         var ws = null;  
42.         var url = null;  
43.         var transports = [];  
44.   
45.         function setConnected(connected) {  
46.             document.getElementById('connect').disabled = connected;  
47.             document.getElementById('disconnect').disabled = !connected;  
48.             document.getElementById('echo').disabled = !connected;  
49.         }  
50.   
51.         function connect() {  
52.             if (!url) {  
53.                 alert('Select whether to use W3C WebSocket or SockJS');  
54.                 return;  
55.             }  
56.               
57.               
58.             //ws = new WebSocket('ws://192.168.10.107:8080/mspjapi/webSocketServer');/* (url.indexOf('sockjs') != -1) ?   
59.                 //new SockJS(url, undefined, {protocols_whitelist: transports}) :  */  
60.                 ws = new SockJS("http://192.168.10.107:8080/mspjapi/webSocketServer/sockjs");  
61.                 //console.log("http://192.168.10.107:8080/mspjapi/webSocketServer/sockjs");  
62.                   
63.             ws.onopen = function () {  
64.                 setConnected(true);  
65.                 log('Info: connection opened.');  
66.             };  
67.               
68.             ws.onmessage = function (event) {  
69.                 log('Received: ' + event.data);  
70.             };  
71.               
72.             ws.onclose = function (event) {  
73.                 setConnected(false);  
74.                 log('Info: connection closed.');  
75.                 log(event);  
76.             };  
77.         }  
78.   
79.         function disconnect() {  
80.             if (ws != null) {  
81.                 ws.close();  
82.                 ws = null;  
83.             }  
84.             setConnected(false);  
85.         }  
86.   
87.         function echo() {  
88.             if (ws != null) {  
89.                 var message = document.getElementById('message').value;  
90.                 log('Sent: ' + message);  
91.                 ws.send(message);  
92.             } else {  
93.                 alert('connection not established, please connect.');  
94.             }  
95.         }  
96.   
97.         function updateUrl(urlPath) {  
98.             if (urlPath.indexOf('sockjs') != -1) {  
99.                 url = urlPath;  
100.                 document.getElementById('sockJsTransportSelect').style.visibility = 'visible';  
101.             }  
102.             else {  
103.               if (window.location.protocol == 'http:') {  
104.                   url = 'ws://' + window.location.host + urlPath;  
105.               } else {  
106.                   url = 'wss://' + window.location.host + urlPath;  
107.               }  
108.               document.getElementById('sockJsTransportSelect').style.visibility = 'hidden';  
109.             }  
110.         }  
111.   
112.         function updateTransport(transport) {  
113.           transports = (transport == 'all') ?  [] : [transport];  
114.         }  
115.           
116.         function log(message) {  
117.             var console = document.getElementById('console');  
118.             var p = document.createElement('p');  
119.             p.style.wordWrap = 'break-word';  
120.             p.appendChild(document.createTextNode(message));  
121.             console.appendChild(p);  
122.             while (console.childNodes.length > 25) {  
123.                 console.removeChild(console.firstChild);  
124.             }  
125.             console.scrollTop = console.scrollHeight;  
126.         }  
127.     </script>  
128. </head>  
129. <body>  
130. <noscript><h2 style="color: #ff0000">Seems your browser doesn't support Javascript! Websockets   
131.     rely on Javascript being enabled. Please enable  
132.     Javascript and reload this page!</h2></noscript>  
133. <div>  
134.     <div id="connect-container">  
135.         <input id="radio1" type="radio" name="group1" onclick="updateUrl('/mspjapi');">  
136.             <label for="radio1">W3C WebSocket</label>  
137.         <br>  
138.         <input id="radio2" type="radio" name="group1" onclick="updateUrl('/spring-websocket-test/sockjs/echo');">  
139.             <label for="radio2">SockJS</label>  
140.         <div id="sockJsTransportSelect" style="visibility:hidden;">  
141.             <span>SockJS transport:</span>  
142.             <select onchange="updateTransport(this.value)">  
143.               <option value="all">all</option>  
144.               <option value="websocket">websocket</option>  
145.               <option value="xhr-polling">xhr-polling</option>  
146.               <option value="jsonp-polling">jsonp-polling</option>  
147.               <option value="xhr-streaming">xhr-streaming</option>  
148.               <option value="iframe-eventsource">iframe-eventsource</option>  
149.               <option value="iframe-htmlfile">iframe-htmlfile</option>  
150.             </select>  
151.         </div>  
152.         <div>  
153.             <button id="connect" onclick="connect();">Connect</button>  
154.             <button id="disconnect" disabled="disabled" onclick="disconnect();">Disconnect</button>  
155.         </div>  
156.         <div>  
157.             <textarea id="message" style="width: 350px">Here is a message!</textarea>  
158.         </div>  
159.         <div>  
160.             <button id="echo" onclick="echo();" disabled="disabled">Echo message</button>  
161.         </div>  
162.     </div>  
163.     <div id="console-container">  
164.         <div id="console"></div>  
165.     </div>  
166. </div>  
167.   
168. <a href="echoendpoint.jsp">echoendpoint test</a>  
169. <a href="websocket2.jsp">echoendpoint test</a>  
170.   
171. </body>  
172. </html>  

最后说下几个坑点：

1、html页面访问限制的问题的：403 Forbidden

[java] view plain copy

1. registry.addHandler(systemWebSocketHandler(),"/webSocketServer/sockjs").setAllowedOrigins("*").withSockJS();  

2、web.xml配置需要升级成3.1

xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_1.xsd"
    version="3.1">

3、web.xml里面所有过滤器需要加上

<async-supported>true</async-supported>

如：

<servlet>
        <servlet-name>SpringMVC</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:spring-mvc.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
        <async-supported>true</async-supported>
    </servlet>