Spring Integration JMS入站网关回复通道没有订阅者

Question

我已经在Spring Integration 5.1.3中使用JMS入站网关进行了测试

但是我收到如下错误：

Caused by: org.springframework.integration.MessageDispatchingException: Dispatcher has no subscribers
at org.springframework.integration.dispatcher.UnicastingDispatcher.doDispatch(UnicastingDispatcher.java:138) ~[spring-integration-core-5.1.3.RELEASE.jar:5.1.3.RELEASE]
at org.springframework.integration.dispatcher.UnicastingDispatcher.dispatch(UnicastingDispatcher.java:105) ~[spring-integration-core-5.1.3.RELEASE.jar:5.1.3.RELEASE]
at org.springframework.integration.channel.AbstractSubscribableChannel.doSend(AbstractSubscribableChannel.java:73) ~[spring-integration-core-5.1.3.RELEASE.jar:5.1.3.RELEASE]

POM：

<dependencies>
    <dependency>
        <groupId>org.springframework.integration</groupId>
        <artifactId>spring-integration-jms</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-activemq</artifactId>
    </dependency>
</dependencies>

我将入站网关配置如下：

@Bean
JmsInboundGateway jmsInboundGateway(
    MessageChannel errorChannel,
    ConnectionFactory connectionFactory,
    DetailJmsProperties properties) {

    final Listener listener = properties.getListener();

    return Jms
        .inboundGateway(connectionFactory)
        .destination("request-queue")
        .requestChannel("inputChannel")
        .replyChannel("outputChannel")
        .defaultReplyQueueName("response-queue")
        .get();
}

然后，服务激活器：

@ServiceActivator(inputChannel = "inputChannel", outputChannel = "outputChannel")
public String process(String request) {
    String response = null;

    try {
        LOGGER.info("Received message content: [{}]", request);
        response = request + " was processed";
    }
    catch (Exception e) {
        LOGGER.error("Error", e);
    }

    return response;
}

顺便说一句，仅当我在Service Activator中删除outputChannel =“ outputChannel”时，它才有效。

这个问题有什么解释吗，我有什么误会吗？

Answer 1

您不能像这样使用DSL工厂（Jms），它们只能用于DSL流中

@Bean
IntegrationFLow flow()
    return IntegrationFlows.from(jmsInboundGateway())
            .handle("service", "process")
            .get();

DSL处理完成所有接线。

它没有通道就可以工作，因为没有输出通道的组件会将答复路由到replyChannel头。

如果您不想使用DSL，则必须直接将入站网关作为Bean连接起来，而不要使用Jms工厂。