在前面的博客中 SpringBoot中的WebSocket讲述了如何搭建基于Springboot的websocket服务端，但是测试的时候是直接用浏览器中的在线测试工具测试的，如何直接写代码测试呢，本篇文章就讲一下如何搭建websocket客户端。

1. 新建一个maven项目命名为websocket_client

1.1 完善pom文件

<?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.owner</groupId>
    <artifactId>websocket_client</artifactId>
    <version>1.0-SNAPSHOT</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.6.RELEASE</version>
    </parent>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

		<!--WebSocket核心依赖包-->
        <dependency>
            <groupId>org.java-websocket</groupId>
            <artifactId>Java-WebSocket</artifactId>
            <version>1.3.8</version>
        </dependency>
    </dependencies>
</project>

1.2 新增application.yml文件

server:
  port: 8002
#  设置服务名
spring:
  application:
    name: websocket-client

1.3 新增启动类

@SpringBootApplication
public class WebSocketApplication {
    public static void main(String[] args){
        SpringApplication.run(WebSocketApplication.class, args);
    }
}

2. WebSocket客户端核心代码实现

2.1 新增WebSocketClient实现类

public class MyWebSocketClient extends WebSocketClient {
    private static final Logger LOGGER = LoggerFactory.getLogger(MyWebSocketClient.class);

    public MyWebSocketClient(URI serverUri) {
        super(serverUri);
    }

    @Override
    public void onOpen(ServerHandshake arg0) {
        // TODO Auto-generated method stub
        LOGGER.info("------ MyWebSocket onOpen ------");
    }

    @Override
    public void onClose(int arg0, String arg1, boolean arg2) {
        // TODO Auto-generated method stub
        LOGGER.info("------ MyWebSocket onClose ------{}",arg1);
    }

    @Override
    public void onError(Exception arg0) {
        // TODO Auto-generated method stub
        LOGGER.info("------ MyWebSocket onError ------{}",arg0);
    }

    @Override
    public void onMessage(String arg0) {
        // TODO Auto-generated method stub
        LOGGER.info("-------- 接收到服务端数据： " + arg0 + "--------");
    }
}

2.2 启动类中添加初始化MyWebSocketClient代码，将MyWebSocketClient交给Spring容器管理

@Bean
    public WebSocketClient webSocketClient() {
        try {
            MyWebSocketClient webSocketClient = new MyWebSocketClient(new URI("ws://127.0.0.1:8001/websocket/12/owner"));
            webSocketClient.connect();
            return webSocketClient;
        } catch (URISyntaxException e) {
            e.printStackTrace();
        }
        return null;
    }

2.3 添加一个WebSocketController类，用发送请求的方式控制WebSocket客户端与服务端通讯

@RestController
public class WebSocketController {

    @Autowired
    private WebSocketClient webSocketClient;

    @RequestMapping("subscribe")
    public String subscribe() {
       // webSocketClient.connect();
        webSocketClient.send("hello sever，i want subscribe data A");
        return "发送订阅成功！！！";
    }
}

3. 测试

首先启动websocket_server,确定websocket服务端正常运行，然后启动websocket_client。
在浏览器中访问http://127.0.0.1:8002/subscribe

再来看一下客户端的日志

上面一条日志是客户端启动时连接服务端成功的日志，第二条是发送订阅信息的日志，服务端返回订阅成功

服务端日志

可以看到服务端正常收到了订阅请求