spring-integration-mqtt 订阅多个主题，并不同主题不同处理方法的完整代码

好的，以下是一个完整的示例代码，其中订阅了两个主题`topic1`和`topic2`，并使用了不同的处理方法来处理不同的主题：

@Configuration
@EnableIntegration
public class MqttConfig {

    @Value("${mqtt.broker.url}")
    private String brokerUrl;

    @Value("${mqtt.broker.username}")
    private String username;

    @Value("${mqtt.broker.password}")
    private String password;

    @Autowired
    private MqttMessageHandler messageHandler;

    @Bean
    public MqttConnectOptions mqttConnectOptions() {
        MqttConnectOptions options = new MqttConnectOptions();
        options.setUserName(username);
        options.setPassword(password.toCharArray());
        return options;
    }

    @Bean
    public MqttPahoClientFactory mqttClientFactory() {
        DefaultMqttPahoClientFactory factory = new DefaultMqttPahoClientFactory();
        factory.setConnectionOptions(mqttConnectOptions());
        return factory;
    }

    @Bean
    public IntegrationFlow mqttInFlow() {
        return IntegrationFlows.from(
                inboundAdapter(),
                e -> e.poller(Pollers.fixedDelay(5000)))
                .route("headers['mqtt_receivedTopic']", router -> router
                        .subFlowMapping("topic1", sf -> sf.handle("topic1Handler", "handleMessage"))
                        .subFlowMapping("topic2", sf -> sf.handle("topic2Handler", "handleMessage")))
                .get();
    }

    @Bean
    public MessageProducerSupport inboundAdapter() {
        MqttPahoMessageDrivenChannelAdapter adapter =
                new MqttPahoMessageDrivenChannelAdapter(
                        "mqttInbound",
                        mqttClientFactory(),
                        "topic1", "topic2");
        adapter.setCompletionTimeout(5000);
        adapter.setConverter(new DefaultPahoMessageConverter());
        adapter.setQos(1);
        return adapter;
    }

    @Bean
    public MessageHandler topic1Handler() {
        return message -> {
            String payload = ((String) message.getPayload());
            // 处理topic1的代码逻辑
            System.out.println("Handling topic1 message: " + payload);
        };
    }

    @Bean
    public MessageHandler topic2Handler() {
        return message -> {
            String payload = ((String) message.getPayload());
            // 处理topic2的代码逻辑
            System.out.println("Handling topic2 message: " + payload);
        };
    }

}

在上面的代码中，我们使用了`MqttPahoMessageDrivenChannelAdapter`来订阅多个主题。在`inboundAdapter()`方法中，我们传入了多个主题。在`mqttInFlow()`方法中，我们使用了`route()`方法来将消息路由到不同的处理器中。在`topic1Handler()`和`topic2Handler()`方法中，我们分别编写了处理`topic1`和`topic2`的代码逻辑。