在SpringMVC中使用WebSocket

2019-11-10 17:19:38

字体：大中小

来源：转载

供稿：网友

SPRingMvc项目的搭建在这里就不做多解释，要在Spring中实现 WebSocket 必须加上 spring-websocket和 spring-messaging两个包，同样，完整的pom.xml给出如下:<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd"> <modelVersion>4.0.0</modelVersion> <groupId>com.656463</groupId> <artifactId>demo-websocket</artifactId> <packaging>war</packaging> <name>demo-websocket Maven Webapp</name> <version>0.0.1-SNAPSHOT</version> <url>http://maven.apache.org</url> <properties> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <spring.version>4.1.6.RELEASE</spring.version> </properties> <dependencies>  <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-core</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-beans</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-aop</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-context-support</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-jdbc</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-web</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupId>org.springframework</groupId> <artifactId>spring-webmvc</artifactId> <version>${spring.version}</version> </dependency> <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> <dependency> <groupId>org.aspectj</groupId> <artifactId>aspectjweaver</artifactId> <version>1.7.4</version> </dependency> <dependency> <groupId>com.google.code.gson</groupId> <artifactId>gson</artifactId> <version>2.7</version> </dependency> <dependency> <groupId>jstl</groupId> <artifactId>jstl</artifactId> <version>1.2</version> </dependency> <dependency> <groupId>taglibs</groupId> <artifactId>standard</artifactId> <version>1.1.2</version> </dependency> <dependency> <groupId>javax.websocket</groupId> <artifactId>javax.websocket-api</artifactId> <version>1.1</version> <scope>provided</scope> </dependency> <dependency> <groupId>javax</groupId> <artifactId>javaee-api</artifactId> <version>7.0</version> <scope>provided</scope> </dependency> </dependencies> <build> <finalName>demo-websocket</finalName> <plugins> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-compiler-plugin</artifactId> <version>3.0</version> <configuration> <source>1.7</source> <target>1.7</target> </configuration> </plugin> <plugin> <groupId>org.apache.tomcat.maven</groupId> <artifactId>tomcat7-maven-plugin</artifactId> <version>2.2</version> <configuration> <port>8080</port> <path>/</path> </configuration> </plugin> </plugins> </build></project>定义一个简单的WebSocket客户端页面，这里只有一个连接和发送消息的功能，这个示例和上个示例的功能类似<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8" %><!DOCTYPE html><html lang="en"><head> <meta charset="utf-8"> <title></title> <script type="text/Javascript" src="/static/js/jquery-1.9.1.js"></script> <script type="text/javascript"> $(function () { var websocket; var target = "ws://192.168.56.101:8080/hello.htm"; if ('WebSocket' in window) { websocket = new WebSocket(target); } else if ('MozWebSocket' in window) { websocket = new MozWebSocket(target); } else { alert('WebSocket is not supported by this browser.'); return; } websocket.onopen = function (evnt) { $("#tou").html("链接服务器成功!") }; websocket.onmessage = function (evnt) { $("#msg").html($("#msg").html() + "<br/>" + evnt.data); }; websocket.onerror = function (evnt) { }; websocket.onclose = function (evnt) { $("#tou").html("与服务器断开了链接!") } $('#send').bind('click', function () { send(); }); function send() { if (websocket != null) { var message = document.getElementById('message').value; websocket.send(message); } else { alert('未与服务器链接.'); } } }); </script></head><body><div id="tou"> webSocket及时聊天Demo程序</div><div id="msg"></div><input type="text" id="message"><button type="button" id="send"> 发送</button></body></html>创建握手拦截器的类 HandInterceptor ，此类实现 HandshakeInterceptor接口。此类的功能有点类似于使用原始J2EE实现的@OnOpen注解package com._656463.demo.websocket.spring;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.HandshakeInterceptor;import javax.servlet.http.HttpServletRequest;import java.util.Map;/** * 拦截器（握手） */public class HandInterceptor implements HandshakeInterceptor { @Override public boolean beforeHandshake(ServerHttpRequest request, ServerHttpResponse response, WebSocketHandler handler, Map<String, Object> map) throws Exception { if (request instanceof ServletServerHttpRequest) { HttpServletRequest req = ((ServletServerHttpRequest) request).getServletRequest(); String userName = "default-user"; // 使用userName区分WebSocketHandler，以便定向发送消息 // String userName = (String) // session.getAttribute("WEBSOCKET_USERNAME"); map.put("WEBSOCKET_USERNAME", userName); req.getSession().setAttribute("WEBSOCKET_USERNAME", userName); } return true; } @Override public void afterHandshake(ServerHttpRequest serverHttpRequest, ServerHttpResponse serverHttpResponse, WebSocketHandler webSocketHandler, Exception e) { }}创建一个类 WebSocketHander，实现 WebSocketHandler接口，此类的主要功能是消息处理中心，相当于使用原始J2EE API实现中的@OnMessage和@OnClose注解功能package com._656463.demo.websocket.spring;import org.springframework.web.socket.*;import java.io.IOException;import java.util.ArrayList;import java.util.List;/** * 消息处理中心 */public class WebSocketHander implements WebSocketHandler { private static final List<WebSocketSession> users = new ArrayList<WebSocketSession>(); /** * 初次链接成功执行 * * @param session * @throws Exception */ @Override public void afterConnectionEstablished(WebSocketSession session) throws Exception { System.out.println("链接成功......"); users.add(session); String userName = (String) session.getAttributes().get("WEBSOCKET_USERNAME"); if (userName != null) { //查询未读消息 int count = 5; session.sendMessage(new TextMessage(count + "")); } } /** * 接受消息处理消息 * * @param session * @param message * @throws Exception */ @Override public void handleMessage(WebSocketSession session, WebSocketMessage<?> message) throws Exception { sendMessageToUsers(new TextMessage(message.getPayload() + "")); } @Override public void handleTransportError(WebSocketSession session, Throwable throwable) throws Exception { if (session.isOpen()) { session.close(); } System.out.println("链接出错，关闭链接......"); users.remove(session); } @Override public void afterConnectionClosed(WebSocketSession session, CloseStatus status) throws Exception { System.out.println("链接关闭......" + status.toString()); users.remove(session); } @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(); } } } /** * 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; } } }}有了握手拦截器和消息处理中心之后，要开启WebSocket，让他工作起来。开启WebSocket有两种方式，一种是基于注解的方式，二是基本XML配置的方式 1、基于注解的方式在springmvc的配置文件中，配置扫描包<context:component-scan base-package="com._656463.demo.websocket.spring"/>创建WebSocketConfig，开启WebSocket，并注册WebSocket的请求路径package com._656463.demo.websocket.spring;import org.springframework.context.annotation.Configuration;import org.springframework.web.servlet.config.annotation.EnableWebMvc;import org.springframework.web.socket.config.annotation.EnableWebSocket;import org.springframework.web.socket.config.annotation.WebSocketConfigurer;import org.springframework.web.socket.config.annotation.WebSocketHandlerRegistry;/** * EnableWebSocket 开启websocket * * @EnableWebMvc //这个标注可以不加，如果有加，要extends WebMvcConfigurerAdapter */@Configuration@EnableWebSocketpublic class WebSocketConfig implements WebSocketConfigurer { @Override public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) { // 支持websocket 的访问链接 registry.addHandler(new WebSocketHander(), "/hello.htm") .addInterceptors(new HandInterceptor()); // 不支持websocket的访问链接 registry.addHandler(new WebSocketHander(), "/sockjs/hello.htm") .addInterceptors(new HandInterceptor()) .withSockJS(); }}2、基于XML配置的方式在springmvc的配置文件中，通过websocket标签配置WebSocket<bean id="websocket" class="com._656463.demo.websocket.spring.WebSocketHander"/><websocket:handlers> <websocket:mapping path="/hello.htm" handler="websocket" /> <websocket:handshake-interceptors> <bean class="com._656463.demo.websocket.spring.HandInterceptor"/> </websocket:handshake-interceptors></websocket:handlers>本次基于Springmvc的WebSocket实例就讲完了，本实例是书生参考网络整理的，希望对你有所帮助

上一篇：HDOJ(HDU).1258 Sum It Up (DFS)

下一篇：wordpress常用插件