在Transformer中获取消息标题-Spring集成

Question

I am using control-bus and inbound-channel-adapter to read contents of csv file. Use case is i should be able to retrieve headers used while starting inbound adapter inside Transformer.

1) Spring-config.xml

<int:channel id="channel">
    <int:queue capacity="10" />
</int:channel>

<file:inbound-channel-adapter id="filesIn" 
    auto-startup="false" directory="file:D:/sample" filename-pattern="*.csv" >
    <int:poller id="poller" fixed-delay="500" />
</file:inbound-channel-adapter>

<int:outbound-channel-adapter auto-startup="true" id="dataout" ref="FileToOutputChannel" method="processContent"/>

<int:transformer id="filetoPojoTransformer" 
    input-channel="filesIn" method="processContent"
    ref="FileToPOJOTransformer" output-channel="dataout"/>



<bean id="FileToPOJOTransformer" class="com.process.FileToPOJOTransformer">

</bean>

<bean id="FileToOutputChannel" class="com.process.FileToOutputChannel">

</bean>

2) FileToPOJOTransformer

 public class FileToPOJOTransformer {

public Message<String> processContent(Message<String> msfile)
{
    System.out.println("This is sample"+msfile.getHeaders());
    // Output here..headers={id=541b6b09-0ace-238b-a30d-25d5a347b93e, timestamp=1502100632757}]
    return msfile;
}

 }

3) Invoke class

  public static void main(String[] args) {
         ApplicationContext context = new ClassPathXmlApplicationContext("HelloWorld.xml");


    DirectChannel controlchannel = (DirectChannel) context.getBean("controlchannel");

    Message<String> message = MessageBuilder.withPayload("@'filesIn.adapter'.start()")
            .setHeader("Message_Header1", "Message_Header1_Value")
            .setHeader("Message_Header2", "Message_Header2_Value")
            .build();
    controlchannel.send(message);

}

I need to have Message_Header1 inside FileToPOJOTransformer's ProcessContent method.

Answer 1

The control bus message is simply to start the adapter. It's headers won't be transferred to whatever message(s) are generated by the adapter. You need to add <int:header-enricher/> between the adapter and transformer to add headers to those messages.