Java整合WebSocket实现实时推送（注解版）
第一次写博客，备份下代码，顺便给需要的同学看看，
网上也有很多Java整合webSocket的例子，大多自己写个类继承 WebSocketConfigurer ，
直接使用注解的比较少，我也看了很多写的运行有问题，要么代码关键部分缺少，想着自己弄一个好了，这个版本在网上某些大佬的基础上实现的，基础代码重复写没意义。
1.加入websocket依赖包
org.springframework
spring-websocket
${spring.version}
org.springframework
spring-messaging
${spring.version}
2.在Namespaces中勾选websocket
3.配置请求地址
4.拦截器配置
public class WebSocketInterceptor extends HttpSessionHandshakeInterceptor {
/**
* TODO 描述该方法的实现功能.
* @see org.springframework.web.socket.server.support.HttpSessionHandshakeInterceptor#beforeHandshake(org.springframework.http.server.ServerHttpRequest, org.springframework.http.server.ServerHttpResponse, org.springframework.web.socket.WebSocketHandler, java.util.Map)
*/
@Override
public boolean beforeHandshake(ServerHttpRequest request, ServerHttpResponse response, WebSocketHandler wsHandler,
Map attributes) throws Exception {
if(request instanceof ServletServerHttpRequest){
ServletServerHttpRequest serverHttpRequest = (ServletServerHttpRequest)request;
//获取参数
String userId = serverHttpRequest .getServletRequest().getParameter("userId");
attributes.put(MyMessageHandler.USER_KEY, userId);
}
return true;
}
} 5.socket用户及msg
/**
* ClassName: MyMessageHandler
* Function: 实现webscoket接口
* @version
*/
@Service
public class MyMessageHandler implements WebSocketHandler {
//用户
public static final String USER_KEY = "socket_user";
/**
* userMap:存储用户连接webscoket信息
* @since JDK 1.7
*/
private final static int size=300;//用户数量
private final static Map userMap;
static {
userMap = new ConcurrentHashMap(size);
}
/**
* 关闭websocket时调用该方法
* @see org.springframework.web.socket.WebSocketHandler#afterConnectionClosed(org.springframework.web.socket.WebSocketSession, org.springframework.web.socket.CloseStatus)
*/
@Override
public void afterConnectionClosed(WebSocketSession session, CloseStatus status) throws Exception {
String userId = this.getUserId(session);
if(StringUtils.isNoneBlank(userId)){
userMap.remove(userId);
System.err.println(userId +"用户已成功关闭会话");
}else{
System.err.println("关闭时，获取用户id为空");
}
}
/**
* 建立websocket连接时调用该方法
* @see org.springframework.web.socket.WebSocketHandler#afterConnectionEstablished(org.springframework.web.socket.WebSocketSession)
*/
@Override
public void afterConnectionEstablished(WebSocketSession session) throws Exception {
String userId = this.getUserId(session);
if(StringUtils.isNoneBlank(userId)){
userMap.put(userId, session);
//session.sendMessage(new TextMessage("用户"+userId+"建立WebSocket连接成功！")); //给所有用户发送消息
}
}
/**
* 客户端调用websocket.send时候，会调用该方法,进行数据通信
* @see org.springframework.web.socket.WebSocketHandler#handleMessage(org.springframework.web.socket.WebSocketSession, org.springframework.web.socket.WebSocketMessage)
*/
@Override
public void handleMessage(WebSocketSession session, WebSocketMessage message) throws Exception {
String msg = message.toString();
String userId = this.getUserId(session);
System.err.println("该"+userId+"用户发送的消息是："+msg);
message = new TextMessage("服务端已经接收到消息，msg="+msg);
session.sendMessage(message);
}
/**
* 传输过程出现异常时，调用该方法
* @see org.springframework.web.socket.WebSocketHandler#handleTransportError(org.springframework.web.socket.WebSocketSession, java.lang.Throwable)
*/
@Override
public void handleTransportError(WebSocketSession session, Throwable e) throws Exception {
WebSocketMessage message = new TextMessage("异常信息："+e.getMessage());
session.sendMessage(message);
}
/**
*
* @see org.springframework.web.socket.WebSocketHandler#supportsPartialMessages()
*/
@Override
public boolean supportsPartialMessages() {
return false;
}
/**
* sendMessageToUser:发给指定用户
*
* @param userId
* @param contents
* @since JDK 1.7
*/
public void sendMessageToUser(String userId,String contents) {
WebSocketSession session = userMap.get(userId);
if(session !=null && session.isOpen()) {
try {
TextMessage message = new TextMessage(contents);
session.sendMessage(message);
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* sendMessageToAllUsers:发给所有的用户
*
* @param contents
* @since JDK 1.7
*/
public void sendMessageToAllUsers(String contents) {
Set userIds = userMap.keySet();
for(String userId: userIds) {
this.sendMessageToUser(userId, contents);
}
}
/**
* getUserId:获取用户id
*
*
* @param session
* @return
* @since JDK 1.7
*/
private String getUserId(WebSocketSession session){
try {
String userId = (String)session.getAttributes().get(USER_KEY);
return userId;
} catch (Exception e) {
e.printStackTrace();
}
return null;
} 6.在springmvc controller中加入
@RequestMapping("/socket")
@Controller
public class WebSocketController {
@Autowired
MyMessageHandler myMessageHandler;
/**
* 对单个用户推送消息
* @return
* @throws ParseException
*/
@RequestMapping("/sendMessageByUser")
@ResponseBody
public String sendMessageByUser(@RequestParam Map contents) throws ParseException{
task();
return "success";
}
/**
* 对所有用户推送消息
* @return
*/
@RequestMapping("/sendMessageByAll")
@ResponseBody
public String sendMessageByAll(@RequestParam Map contents){
myMessageHandler.sendMessageToAllUsers(contents.get("msg").toString());
return "success";
}
} 7.前端js
$(document).ready(function () {
window.websocket={};
var userId='webPower';
var api='你的IP';
var app={
/**
*初始化socket,判断是否支持webSocket
*/
initSocket:function () {
if('WebSocket' in window) {
websocket = new WebSocket("ws://"+api+"/socketServer?userId="+userId);
} else if('MozWebSocket' in window) {
websocket = new MozWebSocket("ws://"+api+"/socketServer?userId="+userId);
} else {
websocket = new SockJS("http://"+api+"/sockjs/socketServer?userId="+userId);
}
app.state();
},
/**
* 状态
*/
state:function () {
// 打开连接时
websocket.onopen = function(evnt) {
console.log("websocket已启用");
};
// 收到消息时
websocket.onmessage = {
};
//出错时
websocket.onerror = function(evnt) {
console.log("与后台握手出现问题!");
};
//关闭时
websocket.onclose = function(evnt) {
console.log("正在关闭 webSocket ");
};
//发送消息
// websocket.send(msg);
}
};
app.initSocket();
});8.效果
