实现游戏公告功能
实现功能：游戏管理里发布游戏公告，其它游戏玩家页面能够马上接受到游戏公告信息。
下面直接上代码案例，这里主要展示关键代码，底部有源码。
一、案例
1、pom.xml文件
主要是添加springBoot和webSocket相关jar包，和一些辅助工具jar包(注意我采用的是springBoot2.1.0版本
<?xml version="1.0" encoding="UTF-8"?>
<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/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion> <groupId>com.jincou.websocket</groupId>
<artifactId>websocketstudy</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging> <name>websocketstudy</name>
<description>Demo project for Spring Boot</description> <parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.0.BUILD-SNAPSHOT</version>
<relativePath/> <!-- lookup parent from repository -->
</parent> <properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
</properties> <dependencies>
<!--springboot和websocket整合包-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-websocket</artifactId>
</dependency> <!--辅助包-->
<dependency>
<groupId>org.webjars</groupId>
<artifactId>webjars-locator</artifactId>
<version>0.32-1</version>
</dependency>
<dependency>
<groupId>org.webjars</groupId>
<artifactId>sockjs-client</artifactId>
<version>1.0.2</version>
</dependency>
<dependency>
<groupId>org.webjars</groupId>
<artifactId>stomp-websocket</artifactId>
<version>2.3.3</version>
</dependency>
<dependency>
<groupId>org.webjars</groupId>
<artifactId>bootstrap</artifactId>
<version>3.3.7</version>
</dependency>
<dependency>
<groupId>org.webjars</groupId>
<artifactId>jquery</artifactId>
<version>3.1.0</version>
</dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</dependency> <dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
</dependency>
</dependencies> <build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build> <repositories>
<repository>
<id>spring-snapshots</id>
<name>Spring Snapshots</name>
<url>https://repo.spring.io/snapshot</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</repository>
<repository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
</repositories>
<pluginRepositories>
<pluginRepository>
<id>spring-snapshots</id>
<name>Spring Snapshots</name>
<url>https://repo.spring.io/snapshot</url>
<snapshots>
<enabled>true</enabled>
</snapshots>
</pluginRepository>
<pluginRepository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</pluginRepository>
</pluginRepositories> </project>
pom.xml
2、WebSocketConfig
这个是websocket配置中心，配置一些核心配置。
import org.springframework.context.annotation.Configuration;
import org.springframework.messaging.simp.config.MessageBrokerRegistry;
import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker;
import org.springframework.web.socket.config.annotation.StompEndpointRegistry;
import org.springframework.web.socket.config.annotation.WebSocketMessageBrokerConfigurer; @Configuration
//注解用于开启使用STOMP协议来传输基于代理（MessageBroker）的消息，这时候控制器（controller）开始支持@MessageMapping,就像是使用@requestMapping一样。
@EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer { /**
* 注册端点，发布或者订阅消息的时候需要连接此端点
* setAllowedOrigins 非必须，*表示允许其他域进行连接
* withSockJS 表示开始sockejs支持
*/
public void registerStompEndpoints(StompEndpointRegistry registry) { registry.addEndpoint("/endpoint-websocket").setAllowedOrigins("*").withSockJS();
} /**
* 配置消息代理(中介)
* enableSimpleBroker 服务端推送给客户端的路径前缀
* setApplicationDestinationPrefixes 客户端发送数据给服务器端的一个前缀
*/
@Override
public void configureMessageBroker(MessageBrokerRegistry registry) { registry.enableSimpleBroker("/topic");
registry.setApplicationDestinationPrefixes("/app"); }
}
3、GameInfoController
管理员发布公告消息对应的接口
/*
*模拟游戏公告
*/
@Controller
public class GameInfoController { //@MessageMapping和@RequestMapping功能类似，用于设置URL映射地址，浏览器向服务器发起请求，需要通过该地址。
//如果服务器接受到了消息，就会对订阅了@SendTo括号中的地址传送消息。
@MessageMapping("/gonggao/chat")
@SendTo("/topic/game_chat")
public OutMessage gameInfo(InMessage message){ return new OutMessage(message.getContent());
}
}
4、管理员页面和用户页面
admin页面和user页面唯一的区别就是管理员多一个发送公告的权限，其它都一样，user1和user2完全一样。
（1）admin.html
<!DOCTYPE html>
<html>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<head>
<title>Hello WebSocket</title>
<link href="/webjars/bootstrap/css/bootstrap.min.css" rel="stylesheet">
<link href="/gonggao/main.css" rel="stylesheet">
<script src="/webjars/jquery/jquery.min.js"></script>
<script src="/webjars/sockjs-client/sockjs.min.js"></script>
<script src="/webjars/stomp-websocket/stomp.min.js"></script>
<script src="/gonggao/app.js"></script>
</head>
<body>
<noscript><h2 style="color: #ff0000">Seems your browser doesn't support Javascript! Websocket relies on Javascript being
enabled. Please enable
Javascript and reload this page!</h2></noscript>
<div id="main-content" class="container">
<div class="row">
<div class="col-md-6">
<form class="form-inline">
<div class="form-group">
<label for="connect">建立连接通道:</label>
<button id="connect" class="btn btn-default" type="submit">Connect</button>
<button id="disconnect" class="btn btn-default" type="submit" disabled="disabled">Disconnect
</button>
</div>
</form>
</div>
<div class="col-md-6">
<form class="form-inline">
<div class="form-group">
<label for="name">发布新公告</label>
<input type="text" id="content" class="form-control" placeholder="请输入...">
</div>
<button id="send" class="btn btn-default" type="submit">发布</button>
</form>
</div>
</div>
<div class="row">
<div class="col-md-12">
<table id="conversation" class="table table-striped">
<thead>
<tr>
<th>游戏公告内容</th>
</tr>
</thead>
<tbody id="notice">
</tbody>
</table>
</div>
</div>
</div>
</body>
</html>
admin.html
（2）user1.html
<!DOCTYPE html>
<html>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<head>
<title>Hello WebSocket</title>
<link href="/webjars/bootstrap/css/bootstrap.min.css" rel="stylesheet">
<link href="/gonggao/main.css" rel="stylesheet">
<script src="/webjars/jquery/jquery.min.js"></script>
<script src="/webjars/sockjs-client/sockjs.min.js"></script>
<script src="/webjars/stomp-websocket/stomp.min.js"></script>
<script src="/gonggao/app.js"></script>
</head>
<body>
<noscript><h2 style="color: #ff0000">Seems your browser doesn't support Javascript! Websocket relies on Javascript being
enabled. Please enable
Javascript and reload this page!</h2></noscript>
<div id="main-content" class="container">
<div class="row">
<div class="col-md-6">
<form class="form-inline">
<div class="form-group">
<label for="connect">建立连接通道:</label>
<button id="connect" class="btn btn-default" type="submit">Connect</button>
<button id="disconnect" class="btn btn-default" type="submit" disabled="disabled">Disconnect
</button>
</div>
</form>
</div> </div>
<div class="row">
<div class="col-md-12">
<table id="conversation" class="table table-striped">
<thead>
<tr>
<th>游戏公告内容</th>
</tr>
</thead>
<tbody id="notice">
</tbody>
</table>
</div>
</div>
</div>
</body>
</html>
user1.html
(3）user2.html
<!DOCTYPE html>
<html>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<head>
<title>Hello WebSocket</title>
<link href="/webjars/bootstrap/css/bootstrap.min.css" rel="stylesheet">
<link href="/gonggao/main.css" rel="stylesheet">
<script src="/webjars/jquery/jquery.min.js"></script>
<script src="/webjars/sockjs-client/sockjs.min.js"></script>
<script src="/webjars/stomp-websocket/stomp.min.js"></script>
<script src="/gonggao/app.js"></script>
</head>
<body>
<noscript><h2 style="color: #ff0000">Seems your browser doesn't support Javascript! Websocket relies on Javascript being
enabled. Please enable
Javascript and reload this page!</h2></noscript>
<div id="main-content" class="container">
<div class="row">
<div class="col-md-6">
<form class="form-inline">
<div class="form-group">
<label for="connect">建立连接通道:</label>
<button id="connect" class="btn btn-default" type="submit">Connect</button>
<button id="disconnect" class="btn btn-default" type="submit" disabled="disabled">Disconnect
</button>
</div>
</form>
</div> </div>
<div class="row">
<div class="col-md-12">
<table id="conversation" class="table table-striped">
<thead>
<tr>
<th>游戏公告内容</th>
</tr>
</thead>
<tbody id="notice">
</tbody>
</table>
</div>
</div>
</div>
</body>
</html>
user2.html
5.app.js
这个是客户端连接websocket的核心，通过html的点击事件来完成。
var stompClient = null; //这个方法仅仅是用来改变样式，不是核心
function setConnected(connected) {
$("#connect").prop("disabled", connected);
$("#disconnect").prop("disabled", !connected);
if (connected) {
$("#conversation").show();
}
else {
$("#conversation").hide();
}
$("#notice").html("");
} //1、建立连接（先连接服务端配置文件中的基站，建立连接，然后订阅服务器目录消息
function connect() {
//1、连接SockJS的endpoint是“endpoint-websocket”，与后台代码中注册的endpoint要一样。
var socket = new SockJS('/endpoint-websocket'); //2、用stom进行包装，规范协议
stompClient = Stomp.over(socket);
stompClient.connect({}, function (frame) { //3、建立通讯
setConnected(true);
console.log('Connected: ' + frame); //4、通过stompClient.subscribe（）订阅服务器的目标是'/topic/game_chat'发送过来的地址，与@SendTo中的地址对应。
stompClient.subscribe('/topic/game_chat', function (result) {
console.info(result)
showContent(JSON.parse(result.body));
});
});
} //2、关闭连接
function disconnect() {
if (stompClient !== null) {
stompClient.disconnect();
}
setConnected(false);
console.log("Disconnected");
} //3、游戏管理员发送公告信息（这个也是游戏用户所没有功能，其它都一样）
function sendName() {
//1、通过stompClient.send 向/app/gonggao/chat 目标 发送消息,这个是在控制器的@messageMapping 中定义的。(/app为前缀，配置里配置）
stompClient.send("/app/gonggao/chat", {}, JSON.stringify({'content': $("#content").val()}));
} //4、订阅的消息显示在客户端指定位置
function showContent(body) {
$("#notice").append("<tr><td>" + body.content + "</td> <td>"+new Date(body.time).toLocaleString()+"</td></tr>");
} $(function () {
$("form").on('submit', function (e) {
e.preventDefault();
});
$( "#connect" ).click(function() { connect(); });
$( "#disconnect" ).click(function() { disconnect(); });
$( "#send" ).click(function() { sendName(); });
});
6、查看运行结果
7、小总结
首先很明显看的出，websocket最大的优点，就是可以服务端主动向客户端发送消息，而此前http只能是客户端向服务端发送请求。
gitHub源码：https://github.com/yudiandemingzi/spring-boot-websocket-study
想太多，做太少，中间的落差就是烦恼。想没有烦恼，要么别想，要么多做。中校【19】