Spring cloud stream 春天的云溪卡夫卡：“；Dispatcher没有订户”；错误

我正在用kafka binder测试spring cloud stream，但出现了一个错误

原因：org.springframework.messaging.MessageDeliveryException:调度程序没有频道“unknown.channel.name”的订户。

pom.xml

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>1.4.0.RELEASE</version>
</parent>

<dependencies>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-stream</artifactId>
        <version>1.1.2.RELEASE</version>
    </dependency>
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-stream-binder-kafka</artifactId>
        <version>1.1.2.RELEASE</version>
    </dependency>
</dependencies>

boss的界面：

public interface SecretaryServingBoss {   
@Input
SubscribableChannel inbox();

@Output
MessageChannel rejected();

@Output
MessageChannel approved();      
}

应用程序属性

server.port=8080
spring.cloud.stream.bindings.inbox.destination=inbox
spring.cloud.stream.bindings.approved.destination=approved
spring.cloud.stream.bindings.rejected.destination=rejected

Employee.java

@EnableBinding(SecretaryServingEmployee.class)
@Component
public class Employee {
    private static Logger logger = LoggerFactory.getLogger(Employee.class);

    private SecretaryServingEmployee adminAssistent;

    @Autowired
    public Employee(SecretaryServingEmployee adminAssistent) {
        this.adminAssistent = adminAssistent;
    }

    @InboundChannelAdapter(value = "inbox")
    public String messageSource() {
        return "You are handsome!!";  // This is the message sent to boss
    }

    @ServiceActivator(inputChannel="approved")
    public void checkApproved(String message) {
        logger.info(":-)");
    }

    @ServiceActivator(inputChannel="rejected")
    public void checkRejected(RejectionLetter letter) {
        logger.warn(":-(");
    } 
}

java

@EnableBinding(SecretaryServingBoss.class)
@Component
public class Boss {
    private SecretaryServingBoss adminAssistent;

    @Autowired
    public Boss(SecretaryServingBoss adminAssistent) {
        this.adminAssistent = adminAssistent;
    }

    @ServiceActivator(inputChannel="inbox")
    public void sign(String content) {
        if (content.contains("You are handsome")) {
            adminAssistent.approved().send(message("nice work"));
        }
        else {
            adminAssistent.rejected().send(message("Don't send me shit"));
        }       
    }

    private <T> Message<T> message(T content) {
        return MessageBuilder.withPayload(content).build();
    }   

}

---

您的应用程序类似乎未正确扫描组件

如果您以Spring引导应用程序的形式运行此应用程序，那么您可以确保是否正确打包了要扫描的类

---

例如，默认情况下，

@SpringBootApplication

的组件扫描会查看

@SpringBootApplication

注释类所在的同一包下的类。

有人可能会从我的经验中受益，整天都在与这个问题斗争，直到我看到@ILayPerumal的回复

我继承了一个带有声明组件扫描的groovy微服务，我想知道他们为什么这么做

例如，默认情况下@SpringBootApplication的组件扫描查看@SpringBootApplication>注释类所在的同一包下的类

所以我重构了包，没有手动更新组件扫描值，这就是我问题的根源

---

如果遇到相同的问题，请检查包扫描。

是的，这是一个Spring Boot应用程序，所有代码都在一个包中。每个包不需要唯一的目标名称吗？e、 g.

@Input（“bossInbox”）

等。唯一的目的地名称修复了该问题。谢谢你，@GaryRussell

@EnableBinding(SecretaryServingBoss.class)
@Component
public class Boss {
    private SecretaryServingBoss adminAssistent;

    @Autowired
    public Boss(SecretaryServingBoss adminAssistent) {
        this.adminAssistent = adminAssistent;
    }

    @ServiceActivator(inputChannel="inbox")
    public void sign(String content) {
        if (content.contains("You are handsome")) {
            adminAssistent.approved().send(message("nice work"));
        }
        else {
            adminAssistent.rejected().send(message("Don't send me shit"));
        }       
    }

    private <T> Message<T> message(T content) {
        return MessageBuilder.withPayload(content).build();
    }   

}

org.springframework.messaging.MessageDeliveryException: Dispatcher has no subscribers for channel 'unknown.channel.name'.; nested exception is org.springframework.integration.MessageDispatchingException: Dispatcher has no subscribers
    at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:81) ~[spring-integration-core-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:423) ~[spring-integration-core-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.integration.channel.AbstractMessageChannel.send(AbstractMessageChannel.java:373) ~[spring-integration-core-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:115) ~[spring-messaging-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:45) ~[spring-messaging-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.messaging.core.AbstractMessageSendingTemplate.send(AbstractMessageSendingTemplate.java:105) ~[spring-messaging-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.handler.AbstractMessageProducingHandler.sendOutput(AbstractMessageProducingHandler.java:292) ~[spring-integration-core-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.integration.handler.AbstractMessageProducingHandler.produceOutput(AbstractMessageProducingHandler.java:212) ~[spring-integration-core-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.integration.handler.AbstractMessageProducingHandler.sendOutputs(AbstractMessageProducingHandler.java:129) ~[spring-integration-core-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.integration.handler.AbstractReplyProducingMessageHandler.handleMessageInternal(AbstractReplyProducingMessageHandler.java:115) ~[spring-integration-core-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.integration.handler.AbstractMessageHandler.handleMessage(AbstractMessageHandler.java:127) ~[spring-integration-core-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.integration.channel.FixedSubscriberChannel.send(FixedSubscriberChannel.java:70) ~[spring-integration-core-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.integration.channel.FixedSubscriberChannel.send(FixedSubscriberChannel.java:64) ~[spring-integration-core-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:115) ~[spring-messaging-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.messaging.core.GenericMessagingTemplate.doSend(GenericMessagingTemplate.java:45) ~[spring-messaging-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.messaging.core.AbstractMessageSendingTemplate.send(AbstractMessageSendingTemplate.java:105) ~[spring-messaging-4.3.2.RELEASE.jar:4.3.2.RELEASE]
    at org.springframework.integration.endpoint.MessageProducerSupport.sendMessage(MessageProducerSupport.java:171) ~[spring-integration-core-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.integration.kafka.inbound.KafkaMessageDrivenChannelAdapter.access$000(KafkaMessageDrivenChannelAdapter.java:47) ~[spring-integration-kafka-2.0.1.RELEASE.jar:na]
    at org.springframework.integration.kafka.inbound.KafkaMessageDrivenChannelAdapter$IntegrationMessageListener.onMessage(KafkaMessageDrivenChannelAdapter.java:197) ~[spring-integration-kafka-2.0.1.RELEASE.jar:na]
    at org.springframework.kafka.listener.adapter.RetryingAcknowledgingMessageListenerAdapter$1.doWithRetry(RetryingAcknowledgingMessageListenerAdapter.java:76) ~[spring-kafka-1.0.5.RELEASE.jar:na]
    at org.springframework.kafka.listener.adapter.RetryingAcknowledgingMessageListenerAdapter$1.doWithRetry(RetryingAcknowledgingMessageListenerAdapter.java:71) ~[spring-kafka-1.0.5.RELEASE.jar:na]
    at org.springframework.retry.support.RetryTemplate.doExecute(RetryTemplate.java:276) ~[spring-retry-1.1.3.RELEASE.jar:na]
    at org.springframework.retry.support.RetryTemplate.execute(RetryTemplate.java:172) ~[spring-retry-1.1.3.RELEASE.jar:na]
    at org.springframework.kafka.listener.adapter.RetryingAcknowledgingMessageListenerAdapter.onMessage(RetryingAcknowledgingMessageListenerAdapter.java:71) ~[spring-kafka-1.0.5.RELEASE.jar:na]
    at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.invokeListener(KafkaMessageListenerContainer.java:597) [spring-kafka-1.0.5.RELEASE.jar:na]
    at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer.access$1800(KafkaMessageListenerContainer.java:222) [spring-kafka-1.0.5.RELEASE.jar:na]
    at org.springframework.kafka.listener.KafkaMessageListenerContainer$ListenerConsumer$ListenerInvoker.run(KafkaMessageListenerContainer.java:772) [spring-kafka-1.0.5.RELEASE.jar:na]
    at java.util.concurrent.Executors$RunnableAdapter.call(Unknown Source) [na:1.8.0_121]
    at java.util.concurrent.FutureTask.run(Unknown Source) [na:1.8.0_121]
    at java.lang.Thread.run(Unknown Source) [na:1.8.0_121]
Caused by: org.springframework.integration.MessageDispatchingException: Dispatcher has no subscribers
    at org.springframework.integration.dispatcher.UnicastingDispatcher.doDispatch(UnicastingDispatcher.java:154) ~[spring-integration-core-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.integration.dispatcher.UnicastingDispatcher.dispatch(UnicastingDispatcher.java:121) ~[spring-integration-core-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:77) ~[spring-integration-core-4.3.1.RELEASE.jar:4.3.1.RELEASE]
    ... 29 common frames omitted