在本章中,将了解和学习如何使用Spring Boot with Web套接字构建交互式Web应用程序。
要使用Web套接字在Spring Boot中构建交互式Web应用程序,需要添加以下依赖项。
Maven用户应在pom.xml 文件中添加以下依赖项。
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-websocket</artifactId> </dependency> <dependency> <groupId>org.webjars</groupId> <artifactId>webjars-locator</artifactId> </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>
Gradle用户可以在build.gradle 文件中添加以下依赖项 -
compile("org.springframework.boot:spring-boot-starter-websocket") compile("org.webjars:webjars-locator") compile("org.webjars:sockjs-client:1.0.2") compile("org.webjars:stomp-websocket:2.3.3") compile("org.webjars:bootstrap:3.3.7") compile("org.webjars:jquery:3.1.0")
创建一个消息处理控制器来处理STOMP消息传递。STOMP消息可以路由到@Controller
类文件。 例如,GreetingController
被映射为处理到目标URL => /hello
的消息。
package com.zyiz.websocketapp; import org.springframework.messaging.handler.annotation.MessageMapping; import org.springframework.messaging.handler.annotation.SendTo; import org.springframework.stereotype.Controller; @Controller public class GreetingController { @MessageMapping("/hello") @SendTo("/topic/greetings") public Greeting greeting(HelloMessage message) throws Exception { Thread.sleep(1000); // simulated delay return new Greeting("Hello, " + message.getName() + "!"); } }
现在,为STOMP消息传递配置Spring。 编写一个扩展AbstractWebSocketMessageBrokerConfigurer
类的WebSocketConfig
类文件,代码如下所示。
package com.zyiz.websocketapp; import org.springframework.context.annotation.Configuration; import org.springframework.messaging.simp.config.MessageBrokerRegistry; import org.springframework.web.socket.config.annotation.AbstractWebSocketMessageBrokerConfigurer; import org.springframework.web.socket.config.annotation.EnableWebSocketMessageBroker; import org.springframework.web.socket.config.annotation.StompEndpointRegistry; @Configuration @EnableWebSocketMessageBroker public class WebSocketConfig extends AbstractWebSocketMessageBrokerConfigurer { @Override public void configureMessageBroker(MessageBrokerRegistry config) { config.enableSimpleBroker("/topic"); config.setApplicationDestinationPrefixes("/app"); } @Override public void registerStompEndpoints(StompEndpointRegistry registry) { registry.addEndpoint("/zyiz-websocket").withSockJS(); } }
@EnableWebSocketMessageBroker
注释用于配置Web套接字消息代理以创建STOMP端点。
可以在src/main/resources/static/index.html
下创建一个浏览器客户端文件,如下所示 -
<!DOCTYPE html> <html> <head> <title>Hello WebSocket</title> <link href = "/webjars/bootstrap/css/bootstrap.min.css" rel = "stylesheet"> <link href = "/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 = "/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">WebSocket connection:</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">What is your name?</label> <input type = "text" id = "name" class = "form-control" placeholder = "Your name here..."> </div> <button id = "send" class = "btn btn-default" type = "submit">Send</button> </form> </div> </div> <div class = "row"> <div class = "col-md-12"> <table id = "conversation" class = "table table-striped"> <thead> <tr> <th>Greetings</th> </tr> </thead> <tbody id = "greetings"></tbody> </table> </div> </div> </div> </body> </html>
创建一个app.js
文件来使用STOMP来消费和生成消息。
var stompClient = null; function setConnected(connected) { $("#connect").prop("disabled", connected); $("#disconnect").prop("disabled", !connected); if (connected) { $("#conversation").show(); } else { $("#conversation").hide(); } $("#greetings").html(""); } function connect() { var socket = new SockJS('/zyiz-websocket'); stompClient = Stomp.over(socket); stompClient.connect({}, function (frame) { setConnected(true); console.log('Connected: ' + frame); stompClient.subscribe('/topic/greetings', function (greeting) { showGreeting(JSON.parse(greeting.body).content); }); }); } function disconnect() { if (stompClient !== null) { stompClient.disconnect(); } setConnected(false); console.log("Disconnected"); } function sendName() { stompClient.send("/app/hello", {}, JSON.stringify({'name': $("#name").val()})); } function showGreeting(message) { $("#greetings").append("<tr><td>" + message + "</td></tr>"); } $(function () { $( "form" ).on('submit', function (e) {e.preventDefault();}); $( "#connect" ).click(function() { connect(); }); $( "#disconnect" ).click(function() { disconnect(); }); $( "#send" ).click(function() { sendName(); }); });
主Spring Boot应用程序的代码如下所示。
package com.zyiz.websocketapp; import org.springframework.boot.SpringApplication; import org.springframework.boot.autoconfigure.SpringBootApplication; @SpringBootApplication public class WebsocketappApplication { public static void main(String[] args) { SpringApplication.run(WebsocketappApplication.class, args); } }
完整的构建配置文件如下所示。
Maven构建文件 - pom.xml
<?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.zyiz</groupId> <artifactId>websocketapp</artifactId> <version>0.0.1-SNAPSHOT</version> <packaging>jar</packaging> <name>websocketapp</name> <description>Demo project for Spring Boot</description> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>1.5.9.RELEASE</version> </parent> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-websocket</artifactId> </dependency> <dependency> <groupId>org.webjars</groupId> <artifactId>webjars-locator</artifactId> </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.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <properties> <java.version>1.8</java.version> </properties> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project>
Gradle构建文件 - build.gradle
buildscript { repositories { mavenCentral() } dependencies { classpath("org.springframework.boot:spring-boot-gradle-plugin:1.5.9.RELEASE") } } apply plugin: 'java' apply plugin: 'eclipse' apply plugin: 'org.springframework.boot' jar { baseName = 'websocketapp' version = '0.1.0' } sourceCompatibility = 1.8 targetCompatibility = 1.8 repositories { mavenCentral() } dependencies { compile("org.springframework.boot:spring-boot-starter-websocket") compile("org.webjars:webjars-locator") compile("org.webjars:sockjs-client:1.0.2") compile("org.webjars:stomp-websocket:2.3.3") compile("org.webjars:bootstrap:3.3.7") compile("org.webjars:jquery:3.1.0") testCompile("org.springframework.boot:spring-boot-starter-test") }
可以创建可执行的JAR文件,并使用以下Maven或Gradle命令运行spring boot应用程序 -
对于Maven,使用如下所示的命令 -
mvn clean install
在“BUILD SUCCESS”之后,可以在target
目录下找到JAR文件。
使用下面给出的命令运行JAR文件 -
java –jar <JARFILE>
在浏览器打开URL => http://localhost:8080/
,得到输出结果如下图所示 -
执行发送和接收消息,如下图所示: