Processor

The Processor interface is used to implement consumers of message exchanges or to implement a Message Translator

Using a processor in a route

Once you have written a class which implements processor like this...

public class MyProcessor implements Processor {
  public void process(Exchange exchange) throws Exception {
    // do something...
  }
}

You can then easily use this inside a route by declaring the bean in Spring, say via the XML (or registering it in JNDI if that is your Registry)

<bean id="myProcessor" class="com.acme.MyProcessor"/>

Then in Camel you can do

from("activemq:myQueue").to("myProcessor");

Using the process DSL

In your route you can also use the process DSL syntax for invoking a processor.

Processor myProcessor = new MyProcessor();
...
from("activemq:myQueue").process(myProcessor);

If you need to lookup the processor in the Registry then you should use the processRef DSL:

from("activemq:myQueue").processRef("myProcessor");

Why use process when you can use to instead?

The process can be used in routes as an anonymous inner class such:

    from("activemq:myQueue").process(new Processor() {
        public void process(Exchange exchange) throws Exception {
            String payload = exchange.getIn().getBody(String.class);
            // do something with the payload and/or exchange here
           exchange.getIn().setBody("Changed body");
       }
    }).to("activemq:myOtherQueue");

This is usable for quickly whirling up some code. If the code in the inner class gets a bit more complicated it is of course advised to refactor it into a separate class.

Turning your processor into a full Component

There is a base class called ProcessorEndpoint which supports the full Endpoint semantics given a Processor instance.

So you just need to create a Component class by deriving from DefaultComponent which returns instances of ProcessorEndpoint. For more details see Writing Components

See Also

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