A.4. Content-based Router
Overview
A content-based router enables you to route messages to the appropriate destination, where the routing decision is based on the message contents. This pattern maps to the corresponding content-based router pattern in Apache Camel.
Figure A.1. Content-based Router Pattern
![Content-based router pattern](https://access.redhat.com/webassets/avalon/d/Red_Hat_JBoss_Fuse-6.1-Apache_Camel_Development_Guide-en-US/images/fde359fba72016f65226a95d9a6e163c/content_based_router.gif)
Example ServiceMix EIP route
Example A.1, “ServiceMix EIP Content-based Route” shows how to define a content-based router using the ServicMix EIP component. If a
test:echo
element is present in the message body, the message is routed to the http://test/pipeline/endpoint
endpoint. Otherwise, the message is routed to the test:recipients
endpoint.
Example A.1. ServiceMix EIP Content-based Route
<eip:content-based-router service="test:router" endpoint="endpoint"> <eip:rules> <eip:routing-rule> <eip:predicate> <eip:xpath-predicate xpath="count(/test:echo) = 1" namespaceContext="#nsContext" /> </eip:predicate> <eip:target> <eip:exchange-target uri="endpoint:test:pipeline:endpoint" /> </eip:target> </eip:routing-rule> <eip:routing-rule> <!-- There is no predicate, so this is the default destination --> <eip:target> <eip:exchange-target service="test:recipients" /> </eip:target> </eip:routing-rule> </eip:rules> </eip:content-based-router>
Equivalent Apache Camel XML route
Example A.2, “Apache Camel Content-based Router Using XML Configuration” shows how to define an equivalent route using Apache Camel XML configuration.
Example A.2. Apache Camel Content-based Router Using XML Configuration
<route> <from uri="jbi:endpoint:http://progress.com/demos/test/router/endpoint"/> <choice> <when> <xpath>count(/test:echo) = 1</xpath> <to uri="jbi:endpoint:http://progress.com/demos/test/pipeline/endpoint"/> </when> <otherwise> <!-- This is the default destination --> <to uri="jbi:service:http://progress.com/demos/test/recipients"/> </otherwise> </choice> </route>
Equivalent Apache Camel Java DSL route
Example A.3, “Apache Camel Content-based Router Using Java DSL” shows how to define an equivalent route using the Apache Camel Java DSL.
Example A.3. Apache Camel Content-based Router Using Java DSL
from("jbi:endpoint:http://progress.com/demos/test/router/endpoint"). choice().when(xpath("count(/test:echo) = 1")).to("jbi:endpoint:http://progress.com/demos/test/pipeline/endpoint"). otherwise().to("jbi:service:http://progress.com/demos/test/recipients");