Java中websocket消息推送的实现代码_Java教程

一.服务层

									package com.demo.websocket;

									import java.io.IOException;

									import java.util.Iterator;

									import java.util.concurrent.ConcurrentLinkedQueue;

									import javax.servlet.ServletContextEvent;

									import javax.servlet.ServletContextListener;

									import org.springframework.context.annotation.Configuration;

									import org.springframework.web.socket.CloseStatus;

									import org.springframework.web.socket.TextMessage;

									import org.springframework.web.socket.WebSocketSession;

									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

									@EnableWebSocket

									public class websocketListener implements WebSocketConfigurer, ServletContextListener{

									  private ConcurrentLinkedQueue<WebSocketSession> sessions = new ConcurrentLinkedQueue<WebSocketSession>();

									  private WebSocketHandlerTest handler;

									  @Override

									  public void contextDestroyed(ServletContextEvent arg0) {

									    // TODO Auto-generated method stub

									  }

									  @Override

									  public void contextInitialized(ServletContextEvent arg0) {

									    // TODO Auto-generated method stub

									  }

									  @Override

									  public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {

									    handler = new WebSocketHandlerTest();

									    registry.addHandler(handler, "/ws/notifymessage.ws");

									    registry.addHandler(handler, "/ws/sockjs/notifymessage.ws").withSockJS();

									    new Thread(handler).start();

									  }

									  class WebSocketHandlerTest extends TextWebSocketHandler implements Runnable{

									    @Override

									    public void afterConnectionClosed(WebSocketSession session, CloseStatus status) throws Exception {

									      sessions.remove(session);

									    }

									    @Override

									    public void afterConnectionEstablished(WebSocketSession session) throws Exception {

									      sessions.add(session);

									    }

									    @Override

									    protected void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception {

									      super.handleTextMessage(session, message);

									    }

									    @Override

									    public void run() {

									      System.out.println("等待推送....");

									      try {

									        int i = 0;

									        for (;;) {

									          synchronized (this) {

									            try {

									              Thread.sleep(3000);

									            } catch (InterruptedException e) {

									              // TODO Auto-generated catch block

									              e.printStackTrace();

									            }

									          }

									          if(i%10==0){

									            nofity("消息推送测试......");

									            System.out.println("推送消息了....");

									          }else{

									            System.out.println("本次不推送消息了....");

									          }

									          i++;

									        }

									      } catch (IOException e) {

									        e.printStackTrace();

									        System.out.println("失败....");

									      }

									    }

									    private void nofity(String message) throws IOException {

									      Iterator<WebSocketSession> iterator = sessions.iterator();

									      while (iterator.hasNext()) {

									        WebSocketSession session = iterator.next();

									        synchronized(session){

									          if(session.isOpen()){

									            session.sendMessage(new TextMessage(message));

									          }else{

									            iterator.remove();

									          }

									        }

									      }

									    }

									  }

									}

二.前台界面监听

									<!DOCTYPE html>

									<html>

									<head>

									<meta charset="UTF-8">

									<title>Insert title here</title>

									</head>

									<body>

									websocket测试界面

									</body>

									<script type="text/javascript">

									var websocketPath = "localhost:8080/demo-web";

									if ('WebSocket' in window) {

									  websocket = new WebSocket("ws://"+websocketPath+"/ws/notifymessage.ws");

									} else if ('MozWebSocket' in window) {

									  websocket = new MozWebSocket("ws://"+websocketPath+"/ws/notifymessage.ws");

									} else {

									  websocket = new SockJS("ws://"+websocketPath+"/ws/notifymessage.ws");

									}

									websocket.onopen = function (evnt) {

									};

									websocket.onmessage = function (evnt) {

									  console.log(evnt);

									};

									websocket.onerror = function (evnt) {

									};

									websocket.onclose = function (evnt) {

									}

									</script>

									</html>

注意web.xml中配置DispatcherServlet控制器

spring-servlet.xml空文件

									<servlet>

									    <servlet-name>spring</servlet-name>

									    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>

									    <init-param>

									      <param-name>contextConfigLocation</param-name>

									      <param-value>/WEB-INF/spring-servlet.xml</param-value>

									    </init-param>

									    <load-on-startup>1</load-on-startup>

									  </servlet>

									  <servlet-mapping>

									    <servlet-name>spring</servlet-name>

									    <url-pattern>*.ws</url-pattern>

									  </servlet-mapping>