Ref Expression Language
Available as of Camel 2.8
The Ref Expression Language is really just a way to lookup a custom Expression from the Registry.
This is particular useable in XML DSLs.
The Splitter in XML DSL can utilize a custom expression using
<bean id="myExpression" class="com.mycompany.MyCustomExpression"/> ... <route> <from uri="seda:a"/> <split> <ref>myExpression</ref> <to uri="mock:b"/> </split> </route>
in this case, the Message coming from the seda:a Endpoint will be splitted using a custom Expression which has the id
myExpression in the Registry.
And the same example using Java DSL:
The Constant language is part of camel-core.