[[MessageTranslator-MessageTranslator]]
== Message Translator

Camel supports the
http://www.enterpriseintegrationpatterns.com/MessageTranslator.html[Message
Translator] from the link:enterprise-integration-patterns.html[EIP
patterns] by using an arbitrary link:processor.html[Processor] in the
routing logic, by using a link:bean-integration.html[bean] to perform
the transformation, or by using transform() in the DSL. You can also use
a link:data-format.html[Data Format] to marshal and unmarshal messages
in different encodings.

image:http://www.enterpriseintegrationpatterns.com/img/MessageTranslator.gif[image]

=== Samples

You can transform a message using Camel's
link:bean-integration.html[Bean Integration] to call any method on a
bean in your link:registry.html[Registry] such as your
link:spring.html[Spring] XML configuration file as follows

[source,java]
----
from("activemq:SomeQueue")
  .bean("myTransformerBean", "myMethodName")
  .to("mqseries:AnotherQueue");
----

Where the "myTransformerBean" would be defined in a Spring XML file or
defined in JNDI etc. You can omit the method name parameter from
beanRef() and the link:bean-integration.html[Bean Integration] will try
to deduce the method to invoke from the message exchange.

or you can add your own explicit link:processor.html[Processor] to do
the transformation

or you can use the DSL to explicitly configure the transformation

You can also use link:spring-xml-extensions.html[Spring XML Extensions]
to do a transformation. Basically any link:expression.html[Expression]
language can be substituted inside the transform element as shown below

Or you can use the link:bean-integration.html[Bean Integration] to
invoke a bean

[source,xml]
----
<route>
  <from uri="activemq:SomeQueue"/>
  <bean ref="myTransformerBean" method="myMethodName"/>
  <to uri="mqseries:AnotherQueue"/>
</route>
----

You can also use link:templating.html[Templating] to consume a message
from one destination, transform it with something like
<<velocity-component,Velocity>> or <<velocity-component,XQuery>> and then send
it on to another destination. For example using InOnly (one way
messaging)

[source,java]
----
from("activemq:My.Queue")
    .to("velocity:com/acme/MyResponse.vm")
    .to("activemq:Another.Queue");
----

If you want to use InOut (request-reply) semantics to process requests
on the *My.Queue* queue on link:activemq.html[ActiveMQ] with a template
generated response, then sending responses back to the JMSReplyTo
Destination you could use this.

[source,java]
----
from("activemq:My.Queue")
    .to("velocity:com/acme/MyResponse.vm");
----

