Page History

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• intercept that intercepts each and every processing step while routing an Exchange in the route.
• interceptFrom that intercepts incoming Exchange in the route.
• interceptSendToEndpoint new in Camel 2.0 that intercepts when an Exchange is about to be sent to the given Endpoint.

TODO: Is being reworked in Camel 2.0, so expect some minor changes
These interceptors supports the following features:

• Predicate using when to only trigger the interceptor in certain conditions
• proceed when used with interceptFrom to continue routing from the point of interception when the interceptor is finished. proceed is default and can be omitted.
• stop when used with interceptFrom will stops routing the Exchange completely. Camel will by default not stop.
• skip when used with interceptSendToEndpoint will skip sending the Exchange to the original intended endpoint. Camel will by default not skip.

Intercept

Intercept is like a regular interceptor that is applied each each processing step the Exchange undergo while its being routed. You can think of it as a AOP before that is applied at each DSL keyword you have defined in your route.

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• .to("bean:validateOrder")
• .to("bean:processOrder")

So in this sample we intercept the Exchange twice.TODO: Add support for when predicate
TODO: Add support for stop predicate (proceed is default)

The when predicate is also support on the intercept so we can attach a Predicate to only trigger the interception under certain conditions.
For instance in the sample below we only intercept if the message body contains the string word Hello:

{snippet:id=e1|lang=java|url=camel/trunk/camel-core/src/test/java/org/apache/camel/processor/intercept/InterceptSimpleRouteWhenTest.java}

Using from Spring DSL

The same hello world sample in Spring DSL would be:

<camelContext ...>
    <intercept>
        <to uri="log:hello"/>
    </intercept>

    <route>
        <from uri="jms:queue:order"/>
        <to uri="bean:validateOrder"/>
        <to uri="bean:handleOrder"/>
    </route>
</camelContext>

And the sample for using the when predicate would be:

{snippet:id=e1|lang=xml|url=camel/trunk/components/camel-spring/src/test/resources/org/apache/camel/spring/processor/SpringInterceptSimpleRouteWhenTest.xml}

InterceptFrom

InterceptFrom is for intercepting any incoming Exchange, in any route (it intercepts all the from DSLs). This allows you to do some custom behavior for received Exchanges. You can provide a specific uri for a given Endpoint then it only applies for that particular route.

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