Spring WebSocket实现消息推送
第一步： 添加Spring WebSocket的依赖jar包
（注：这里使用maven方式添加 手动添加的同学请自行下载相应jar包放到lib目录）
<!-- 使用spring websocket依赖的jar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>
第二步：建立一个类实现WebSocketConfigurer接口
package com.quicksand.push; import org.springframework.context.annotation.Bean; import org.springframework.context.annotation.Configuration; import org.springframework.web.servlet.config.annotation.EnableWebMvc; import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter; import org.springframework.web.socket.config.annotation.EnableWebSocket; import org.springframework.web.socket.config.annotation.WebSocketConfigurer; import org.springframework.web.socket.config.annotation.WebSocketHandlerRegistry; import org.springframework.web.socket.handler.TextWebSocketHandler; @Configuration @EnableWebMvc @EnableWebSocket public class SpringWebSocketConfig extends WebMvcConfigurerAdapter implements WebSocketConfigurer { public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) { registry.addHandler(webSocketHandler(),"/websocket/socketServer.do").addInterceptors(new SpringWebSocketHandlerInterceptor()); registry.addHandler(webSocketHandler(), "/sockjs/socketServer.do").addInterceptors(new SpringWebSocketHandlerInterceptor()).withSockJS(); } @Bean public TextWebSocketHandler webSocketHandler(){ return new SpringWebSocketHandler(); } }
第三步：继承WebSocketHandler对象。该对象提供了客户端连接,关闭,错误,发送等方法,重写这几个方法即可实现自定义业务逻辑
package com.quicksand.push; import java.io.IOException; import java.util.ArrayList; import org.apache.log4j.Logger; import org.springframework.web.socket.CloseStatus; import org.springframework.web.socket.TextMessage; import org.springframework.web.socket.WebSocketSession; import org.springframework.web.socket.handler.TextWebSocketHandler; public class SpringWebSocketHandler extends TextWebSocketHandler { private static final ArrayList<WebSocketSession> users;//这个会出现性能问题，最好用Map来存储，key用userid private static Logger logger = Logger.getLogger(SpringWebSocketHandler.class); static { users = new ArrayList<WebSocketSession>(); } public SpringWebSocketHandler() { // TODO Auto-generated constructor stub } /** * 连接成功时候，会触发页面上onopen方法 */ public void afterConnectionEstablished(WebSocketSession session) throws Exception { // TODO Auto-generated method stub System.out.println("connect to the websocket success......当前数量:"+users.size()); users.add(session); //这块会实现自己业务，比如，当用户登录后，会把离线消息推送给用户 //TextMessage returnMessage = new TextMessage("你将收到的离线"); //session.sendMessage(returnMessage); } /** * 关闭连接时触发 */ public void afterConnectionClosed(WebSocketSession session, CloseStatus closeStatus) throws Exception { logger.debug("websocket connection closed......"); String username= (String) session.getAttributes().get("WEBSOCKET_USERNAME"); System.out.println("用户"+username+"已退出！"); users.remove(session); System.out.println("剩余在线用户"+users.size()); } /** * js调用websocket.send时候，会调用该方法 */ @Override protected void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception { super.handleTextMessage(session, message); } public void handleTransportError(WebSocketSession session, Throwable exception) throws Exception { if(session.isOpen()){session.close();} logger.debug("websocket connection closed......"); users.remove(session); } public boolean supportsPartialMessages() { return false; } /** * 给某个用户发送消息 * * @param userName * @param message */ public void sendMessageToUser(String userName, TextMessage message) { for (WebSocketSession user : users) { if (user.getAttributes().get("WEBSOCKET_USERNAME").equals(userName)) { try { if (user.isOpen()) { user.sendMessage(message); } } catch (IOException e) { e.printStackTrace(); } break; } } } /** * 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(); } } } }
第四步：继承HttpSessionHandshakeInterceptor对象。该对象作为页面连接websocket服务的拦截器,代码如下：
package com.quicksand.push; import java.util.Map; import javax.servlet.http.HttpSession; import org.springframework.http.server.ServerHttpRequest; import org.springframework.http.server.ServerHttpResponse; import org.springframework.http.server.ServletServerHttpRequest; import org.springframework.web.socket.WebSocketHandler; import org.springframework.web.socket.server.support.HttpSessionHandshakeInterceptor; /** * WebSocket拦截器 * @author WANG * */ public class SpringWebSocketHandlerInterceptor extends HttpSessionHandshakeInterceptor { @Override public boolean beforeHandshake(ServerHttpRequest request, ServerHttpResponse response, WebSocketHandler wsHandler, Map<String, Object> attributes) throws Exception { // TODO Auto-generated method stub System.out.println("Before Handshake"); if (request instanceof ServletServerHttpRequest) { ServletServerHttpRequest servletRequest = (ServletServerHttpRequest) request; HttpSession session = servletRequest.getServletRequest().getSession(false); if (session != null) { //使用userName区分WebSocketHandler，以便定向发送消息 String userName = (String) session.getAttribute("SESSION_USERNAME"); if (userName==null) { userName="default-system"; } attributes.put("WEBSOCKET_USERNAME",userName); } } return super.beforeHandshake(request, response, wsHandler, attributes); } @Override public void afterHandshake(ServerHttpRequest request, ServerHttpResponse response, WebSocketHandler wsHandler, Exception ex) { // TODO Auto-generated method stub super.afterHandshake(request, response, wsHandler, ex); } }
第5步 让SpringWebSocketConfig配置类随spring容器启动 spring文件中加入如下代码：
<!-- websocket相关扫描，主要扫描：WebSocketConfig 如果前面配置能扫描到此类则可以不加 --> <context:component-scan base-package="com.quicksand.push"/>
-------------------------------------------------------------------------到这里就算完成啦 下面准备测试-------------------------------------------------------------
1.定义一个控制器用来做连接标识和发送消息
package com.quicksand.controller; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import org.springframework.context.annotation.Bean; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.ResponseBody; import org.springframework.web.servlet.ModelAndView; import org.springframework.web.socket.TextMessage; import com.quicksand.push.SpringWebSocketHandler; @Controller public class WebsocketController { @Bean//这个注解会从Spring容器拿出Bean public SpringWebSocketHandler infoHandler() { return new SpringWebSocketHandler(); } @RequestMapping("/websocket/login") public ModelAndView login(HttpServletRequest request, HttpServletResponse response) throws Exception { String username = request.getParameter("username"); System.out.println(username+"登录"); HttpSession session = request.getSession(false); session.setAttribute("SESSION_USERNAME", username); //response.sendRedirect("/quicksand/jsp/websocket.jsp"); return new ModelAndView("websocket"); } @RequestMapping("/websocket/send") @ResponseBody public String send(HttpServletRequest request) { String username = request.getParameter("username"); infoHandler().sendMessageToUser(username, new TextMessage("你好，测试！！！！")); return null; } }
2.建立登录页面
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <body> <h2>Hello World!</h2> <body> <!-- ship是我的项目名--> <form action="websocket/login.do"> 登录名：<input type="text" name="username"/> <input type="submit" value="登录"/> </form> </body> </body> </html>
3.建立发消息页面
<%@ page language="java" contentType="text/html; charset=utf-8" pageEncoding="utf-8"%> <!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>Insert title here</title> </head> <body> <script type="text/javascript" src="http://cdn.bootcss.com/jquery/3.1.0/jquery.min.js"></script> <script type="text/javascript" src="http://cdn.bootcss.com/sockjs-client/1.1.1/sockjs.js"></script> <script type="text/javascript"> var websocket = null; if ('WebSocket' in window) { websocket = new WebSocket("ws://localhost:8080/quicksand/websocket/socketServer.do"); } else if ('MozWebSocket' in window) { websocket = new MozWebSocket("ws://localhost:8080/quicksand/websocket/socketServer.do"); } else { websocket = new SockJS("http://localhost:8080/quicksand/sockjs/socketServer.do"); } websocket.onopen = onOpen; websocket.onmessage = onMessage; websocket.onerror = onError; websocket.onclose = onClose; function onOpen(openEvt) { //alert(openEvt.Data); } function onMessage(evt) { alert(evt.data); } function onError() {} function onClose() {} function doSend() { if (websocket.readyState == websocket.OPEN) { var msg = document.getElementById("inputMsg").value; websocket.send(msg);//调用后台handleTextMessage方法 alert("发送成功!"); } else { alert("连接失败!"); } }
window.close=function()
{
websocket.onclose();
}
</script> 请输入：<textarea rows="5" cols="10" id="inputMsg" name="inputMsg"></textarea> <button onclick="doSend();">发送</button> </body> </html>
测试结果如下图：
