springboot-rabbitMQ-websocket java 注解实现

下面是一个简单的 Spring Boot + RabbitMQ + WebSocket 的实现，以注解方式完成：

1. 首先，需要在 pom.xml 中添加以下依赖：

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

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

2. 在 application.properties 中添加 RabbitMQ 和 WebSocket 的配置：

# RabbitMQ配置
spring.rabbitmq.host=localhost
spring.rabbitmq.port=5672
spring.rabbitmq.username=guest
spring.rabbitmq.password=guest
spring.rabbitmq.virtual-host=/

# WebSocket配置
server.port=8080

3. 创建一个 RabbitMQ 的配置类，用于定义交换机、队列、绑定等：

@Configuration
public class RabbitMQConfig {

    @Bean
    public TopicExchange exchange() {
        return new TopicExchange("websocket-exchange");
    }

    @Bean
    public Queue queue() {
        return new Queue("websocket-queue");
    }

    @Bean
    public Binding binding() {
        return BindingBuilder.bind(queue()).to(exchange()).with("websocket.*");
    }
}

4. 创建一个 RabbitMQ 消息发送者：

@Component
public class RabbitMQSender {

    @Autowired
    private RabbitTemplate rabbitTemplate;

    public void send(String message) {
        rabbitTemplate.convertAndSend("websocket-exchange", "websocket.message", message);
    }
}

5. 创建一个 WebSocket 处理器，用于接收和发送消息：

@Component
public class WebSocketHandler extends TextWebSocketHandler {

    private final List<WebSocketSession> sessions = new CopyOnWriteArrayList<>();

    @Override
    public void afterConnectionEstablished(WebSocketSession session) throws Exception {
        sessions.add(session);
    }

    @Override
    public void afterConnectionClosed(WebSocketSession session, CloseStatus status) throws Exception {
        sessions.remove(session);
    }

    @Override
    protected void handleTextMessage(WebSocketSession session, TextMessage message) throws Exception {
        String payload = message.getPayload();
        sendMessage(payload);
    }

    public void sendMessage(String message) throws IOException {
        for (WebSocketSession session : sessions) {
            session.sendMessage(new TextMessage(message));
        }
    }
}

6. 创建一个 RabbitMQ 消息接收者，用于将消息发送给 WebSocket 处理器：

@Component
public class RabbitMQReceiver {

    @Autowired
    private WebSocketHandler webSocketHandler;

    @RabbitListener(queues = "websocket-queue")
    public void receive(String message) throws IOException {
        webSocketHandler.sendMessage(message);
    }
}

7. 最后，在控制器中定义一个 API，用于发送消息到 RabbitMQ：

@RestController
public class MessageController {

    @Autowired
    private RabbitMQSender rabbitMQSender;

    @PostMapping("/send")
    public String sendMessage(@RequestBody String message) {
        rabbitMQSender.send(message);
        return "OK";
    }
}

以上就是一个简单的 Spring Boot + RabbitMQ + WebSocket 的实现，可以通过发送 POST 请求到 /send 接口来发送消息，WebSocket 处理器会接收到消息并发送给所有连接的客户端。