SpringBoot--05--整合WebSocket,实现全双工通信

以下是一个使用Spring Boot整合WebSocket的简单示例，实现全双工通讯：

1. 添加依赖到pom.xml：

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

2. 配置WebSocket：

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
@EnableWebSocketMessageBroker
public class WebSocketConfig implements WebSocketMessageBrokerConfigurer {
    
    @Override
    public void registerStompEndpoints(StompEndpointRegistry registry) {
        registry.addEndpoint("/ws").withSockJS();
    }
 
    @Override
    public void configureMessageBroker(MessageBrokerRegistry registry) {
        registry.enableSimpleBroker("/topic");
        registry.setApplicationDestinationPrefixes("/app");
    }
}

3. 创建控制器处理WebSocket请求：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.messaging.handler.annotation.MessageMapping;
import org.springframework.messaging.handler.annotation.SendTo;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.ResponseBody;
 
@Controller
public class WebSocketController {
 
    @Autowired
    private SimpMessagingTemplate simpMessagingTemplate;
 
    @MessageMapping("/chat.sendMessage")
    @SendTo("/topic/public")
    public ChatMessage sendMessage(ChatMessage message) {
        return message;
    }
 
    @MessageMapping("/chat.addUser")
    @SendTo("/topic/public")
    public ChatMessage addUser(Principal principal, ChatMessage message) {
        message.setUsername(principal.getName());
        return message;
    }
}
 
class ChatMessage {
    private String username;
    private String message;
    // getters and setters
}

4. 前端JavaScript代码连接WebSocket并发送接收消息：

var socket = new SockJS('/ws');
stompClient = Stomp.over(socket);
stompClient.connect({}, function(frame) {
    console.log('Connected: ' + frame);
    stompClient.subscribe('/topic/public', function(message) {
        // Handle incoming messages
        showMe