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

@Configuration
@EnableWebMvc
@EnableWebSocket
public class WebSocketConfig extends WebMvcConfigurerAdapter implements WebSocketConfigurer{

@Override
public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
registry.addHandler(systemWebSocketHandler(),"/webSocketServer");
registry.addHandler(systemWebSocketHandler(),"/webSocketServer/sockjs").setAllowedOrigins("*").withSockJS();
//registry.addHandler(systemWebSocketHandler(),"/webSocketServer").addInterceptors(new WebSocketHandshakeInterceptor());
//registry.addHandler(systemWebSocketHandler(), "/sockjs/webSocketServer").addInterceptors(new WebSocketHandshakeInterceptor()).withSockJS();
//registry.addHandler(systemWebSocketHandler(), "/webSocketServer/sockjs").withSockJS();
/*registry.addHandler(systemWebSocketHandler(),"/ws").addInterceptors(new WebSocketHandshakeInterceptor());
registry.addHandler(systemWebSocketHandler(), "/ws/sockjs").addInterceptors(new WebSocketHandshakeInterceptor())
.withSockJS();*/
}

@Bean
public WebSocketHandler systemWebSocketHandler(){
return new SystemWebSocketHandler();
}

import java.io.IOException;
import java.util.ArrayList;
import java.util.Date;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.messaging.Message;
import org.springframework.web.socket.CloseStatus;
import org.springframework.web.socket.TextMessage;
import org.springframework.web.socket.WebSocketHandler;
import org.springframework.web.socket.WebSocketMessage;
import org.springframework.web.socket.WebSocketSession;

import com.mspj.frame.core.web.controller.BaseWebControllerImpl;

public class SystemWebSocketHandler implements WebSocketHandler {

private Logger log = LoggerFactory.getLogger(SystemWebSocketHandler.class);

private static final ArrayList<WebSocketSession> users = new ArrayList<WebSocketSession>();;

@Override
public void afterConnectionEstablished(WebSocketSession session) throws Exception {
System.out.println("ConnectionEstablished");
log.debug("ConnectionEstablished");
users.add(session);

session.sendMessage(new TextMessage("connect"));
session.sendMessage(new TextMessage("new_msg"));

}

@Override
public void handleMessage(WebSocketSession session, WebSocketMessage<?> message) throws Exception {
System.out.println("handleMessage" + message.toString());
log.debug("handleMessage" + message.toString());
//sendMessageToUsers();
session.sendMessage(new TextMessage(new Date() + ""));
}

@Override
public void handleTransportError(WebSocketSession session, Throwable exception) throws Exception {
if(session.isOpen()){
session.close();
}
users.remove(session);

log.debug("handleTransportError" + exception.getMessage());
}

@Override
public void afterConnectionClosed(WebSocketSession session, CloseStatus closeStatus) throws Exception {
users.remove(session);
log.debug("afterConnectionClosed" + closeStatus.getReason());

}

@Override
public boolean supportsPartialMessages() {
return false;
}

/**
* 给所有在线用户发送消息
*
* @param message
*/
public void sendMessageToUsers(TextMessage message) {
for (WebSocketSession user : users) {
try {
if (user.isOpen()) {
user.sendMessage(message);
}
} catch (IOException e) {
e.printStackTrace();
}
}
}

}

前端调式页面代码
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>WebSocket/SockJS Echo Sample (Adapted from Tomcat's echo sample)</title>
<style type="text/css">
#connect-container {
float: left;
width: 400px
}

#connect-container div {
padding: 5px;
}

#console-container {
float: left;
margin-left: 15px;
width: 400px;
}

#console {
border: 1px solid #CCCCCC;
border-right-color: #999999;
border-bottom-color: #999999;
height: 170px;
overflow-y: scroll;
padding: 5px;
width: 100%;
}

#console p {
padding: 0;
margin: 0;
}
</style>

<script src="http://cdn.sockjs.org/sockjs-0.3.min.js"></script>

<script type="text/javascript">
var ws = null;
var url = null;
var transports = [];

function setConnected(connected) {
document.getElementById('connect').disabled = connected;
document.getElementById('disconnect').disabled = !connected;
document.getElementById('echo').disabled = !connected;
}

function connect() {
if (!url) {
alert('Select whether to use W3C WebSocket or SockJS');
return;
}

//ws = new WebSocket('ws://192.168.10.107:8080/mspjapi/webSocketServer');/* (url.indexOf('sockjs') != -1) ?
//new SockJS(url, undefined, {protocols_whitelist: transports}) : */
ws = new SockJS("http://192.168.10.107:8080/mspjapi/webSocketServer/sockjs");
//console.log("http://192.168.10.107:8080/mspjapi/webSocketServer/sockjs");

ws.onopen = function () {
setConnected(true);
log('Info: connection opened.');
};

ws.onmessage = function (event) {
log('Received: ' + event.data);
};

ws.onclose = function (event) {
setConnected(false);
log('Info: connection closed.');
log(event);
};
}

function disconnect() {
if (ws != null) {
ws.close();
ws = null;
}
setConnected(false);
}

function echo() {
if (ws != null) {
var message = document.getElementById('message').value;
log('Sent: ' + message);
ws.send(message);
} else {
alert('connection not established, please connect.');
}
}

function updateUrl(urlPath) {
if (urlPath.indexOf('sockjs') != -1) {
url = urlPath;
document.getElementById('sockJsTransportSelect').style.visibility = 'visible';
}
else {
if (window.location.protocol == 'http:') {
url = 'ws://' + window.location.host + urlPath;
} else {
url = 'wss://' + window.location.host + urlPath;
}
document.getElementById('sockJsTransportSelect').style.visibility = 'hidden';
}
}

function updateTransport(transport) {
transports = (transport == 'all') ? [] : [transport];
}

function log(message) {
var console = document.getElementById('console');
var p = document.createElement('p');
p.style.wordWrap = 'break-word';
p.appendChild(document.createTextNode(message));
console.appendChild(p);
while (console.childNodes.length > 25) {
console.removeChild(console.firstChild);
}
console.scrollTop = console.scrollHeight;
}
</script>
</head>
<body>
<noscript><h2 style="color: #ff0000">Seems your browser doesn't support Javascript! Websockets
rely on Javascript being enabled. Please enable
Javascript and reload this page!</h2></noscript>
<div>
<div id="connect-container">
<input id="radio1" type="radio" name="group1" onclick="updateUrl('/mspjapi');">
<label for="radio1">W3C WebSocket</label>
<br>
<input id="radio2" type="radio" name="group1" onclick="updateUrl('/spring-websocket-test/sockjs/echo');">
<label for="radio2">SockJS</label>
<div id="sockJsTransportSelect" style="visibility:hidden;">
<span>SockJS transport:</span>
<select onchange="updateTransport(this.value)">
<option value="all">all</option>
<option value="websocket">websocket</option>
<option value="xhr-polling">xhr-polling</option>
<option value="jsonp-polling">jsonp-polling</option>
<option value="xhr-streaming">xhr-streaming</option>
<option value="iframe-eventsource">iframe-eventsource</option>
<option value="iframe-htmlfile">iframe-htmlfile</option>
</select>
</div>
<div>
<button id="connect" onclick="connect();">Connect</button>
<button id="disconnect" disabled="disabled" onclick="disconnect();">Disconnect</button>
</div>
<div>
<textarea id="message" style="width: 350px">Here is a message!</textarea>
</div>
<div>
<button id="echo" onclick="echo();" disabled="disabled">Echo message</button>
</div>
</div>
<div id="console-container">
<div id="console"></div>
</div>
</div>

<a href="echoendpoint.jsp">echoendpoint test</a>
<a href="websocket2.jsp">echoendpoint test</a>

</body>
</html>

最后说下几个坑点：

1、html页面访问限制的问题的：403 Forbidden

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>