java - 使用 ControlBus 发送消息以打开 Spring Integration 入站适配器时出错

Question

这是我第一次尝试使用 ControlBus 打开/关闭入站 channel 适配器。

为简单起见，我通过将一个空文件写入一个由入站文件适配器监视的目录(这个永远打开)来发送我的控制消息，然后我将其路由到一个将打开的服务激活器/关闭我的其他入站适配器。

<int:channel id="controlBusChannel" />
<int:control-bus input-channel="controlBusChannel" auto-startup="true"/>
<file:inbound-channel-adapter id="controlFilesIn" directory="file:/tmp/control/input" prevent-duplicates="true" auto-startup="true">
    <int:poller id="poller" fixed-delay="500"/>
</file:inbound-channel-adapter>
<int:service-activator input-channel="controlFilesIn" output-channel="controlFilesOut" ref="controlFileHandler" method="handleUpdate"/>
<bean id="controlFileHandler" class="com.myproj.integration.ControlBusController"/>
<file:outbound-channel-adapter id="controlFilesOut" directory="file:/tmp/control/output" delete-source-files="true" />

<file:inbound-channel-adapter id="filesIn" directory="file:/tmp/filesIn/input" prevent-duplicates="true" filter="FileFilterOnLastModifiedTime" auto-startup="false">
    <int:poller id="poller" fixed-delay="500"/>
</file:inbound-channel-adapter>

在我的 ControlBusController bean 中:

@Component
public class ControlBusController implements ApplicationContextAware {
    final static Logger logger = LoggerFactory.getLogger(ControlBusController.class);

    private ApplicationContext ctx;

    public File handleUpdate(File input) throws ParseException, IOException, FileNotFoundException {
        String fileName = input.getName();
        logger.info("===================================");
        logger.info("Triggering control bus update by " + fileName);
        String[] fnArray = fileName.split("_");
        String inputChannel = fnArray[1];
        String inputCommand = fnArray[2];
        if ("FILESIN".equals(inputChannel) && "START".equals(inputCommand)) {
            MessageChannel channel = ctx.getBean("controlBusChannel", MessageChannel.class);
            if (channel != null) {
                String controlMessage = "@filesIn.start()";
                logger.info("Sending control message: " + controlMessage);
                channel.send(new GenericMessage<>(controlMessage));
            } else logger.error("Could not get Message Channel from context or context was null");
        }
        return input;
    }

    @Override
    public void setApplicationContext(ApplicationContext ac) throws BeansException {
        this.ctx = ac;
    }
}

消息被发送到 controlBusChannel，但我收到一条错误消息:

Caused by: org.springframework.expression.EvaluationException: The method 'start' is not supported by this command processor. If using the Control Bus, consider adding @ManagedOperation or @ManagedAttribute.
        at org.springframework.integration.handler.ExpressionCommandMessageProcessor$ExpressionCommandMethodResolver.validateMethod(ExpressionCommandMessageProcessor.java:111)

filesIn 已声明为我的适配器的 ID，如上面的 XML 片段所示。

有什么想法吗？谢谢!

附言我试过只放入 @ManagedOperation/@ManagedAttribute 注释，但它们似乎没有任何积极效果。

Answer 1

因为你没有 channel <int-file:inbound-channel-adapter> 上的属性, 但只是一个 id , 所以 channel 是自动创建的，它与 id 完全一致.适配器本身有一个像 filesIn.adapter 这样的 bean 名称。 .

因此，您必须将 ControlBus 命令表达式更改为:

String controlMessage = "@'filesIn.adapter'.start()";