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javaapache-camelenterprise-integration

In Camel @Produce produces what, and @Consume consumes what?

As an irrelevant poorly opinionated opinion, I find apache camel docs too presumptuous in presuming the reader has a background in camel already.

In normal terms, a web service provider is a producer, and a client of the service it produces is a consumer.

Let's look at http://camel.apache.org/pojo-producing.html.

Which says, there are two diff ways to send messages to Camel Endpoint.

@EndpointInjecct (uri ..) ProducerTemplate ...

Is it saying

  • Hey I;m an endpoint and this is my uri and a template to hit me with, so hit me

  • Or, hmm ... there is an endpoint with this uri somewhere out there beneath the clear blue skies, and here is the template I presume I'm gonna hit it with

???

Similarly, is @Produce, and ProducerTemplate

  • specifying I'm an endpoint that is going to get hit?
  • or specifying the template of a producer I am going to hit??

Similarly, @Consume,

  • Am I specifying I am a consumer?
  • Or that I am specifying how I am to be consumed?

And BTW, the uri in @Produce(uri) or EndpointInjection (uri)

  • am I sending to this uri?
  • or recceiving under this uri?
Solution

  • As per your doubts, below I'm trying to clarify:

    @EndpointInject (uri=...) ProducerTemplate ...

    This means rather your 2nd option:

    there is an endpoint with this uri somewhere out there beneath the clear blue skies, and here is the template I presume I'm gonna hit it with

    I.e., uses the Camel API, ProducerTemplate, to send the message to another endpoint, defined on the uri.

    Regarding the @Produce and ProducerTemplate, the closest guess here would be

    specifying the template of a producer I am going to hit

    Although technically the endpoint specified to be hit on the uri is not to be mistaken with the producer in Camel terminology, it is simply an endpoint, which in this context would be called a consumer since it receives messages.

    Analogously, regarding @Consume marks the method as a consumer method, i.e. the one that handles the endpoint incomming messages, endpoint specified by the uri.

    Hope this is of some help.