THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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Variable | Type | Description |
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this | Exchange | the Exchange is the root object |
exchange | Exchange | the Exchange object |
exception | Throwable | the Exchange exception (if any) |
exchangeId | String | the exchange id |
fault | Message | the Fault message (if any) |
body | Object | Camel 2.11: The IN message body. |
request | Message | the exchange.in message |
response | Message | the exchange.out message (if any) |
properties | Map | the exchange properties |
property(name) | Object | the property by the given name |
property(name, type) | Type | the property by the given name as the given type |
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SpEL expressions need to be surrounded by #{ }@ delimiters since expression templating is enabled. This allows you to combine SpEL expressions with regular text and use this as extremely lightweight template language.
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from("direct:example").setBody(spel("Hello #{request.body}! What a beautiful #{request.headers['dayOrNight']}")).to("mock:result");
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In the route above, notice spel is a static method which we need to import from org.apache.camel.language.spel.SpelExpression.spel, as we use spel as an Expression passed in as a parameter to the setBody method. Though if we use the fluent API we can do this instead:
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from("direct:example").setBody().spel("Hello #{request.body}! What a beautiful #{request.headers['dayOrNight']}").to("mock:result"); |
Notice we now use the spel method from the setBody() method. And this does not require us to static import the spel method from org.apache.camel.language.spel.SpelExpression.spel.
And sent a message with the string "World" in the body, and a header "dayOrNight" with value "day":
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#{@foo.bar == 'xyz'} |
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SpEL in enterprise integration patterns
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from("direct:foo").filter().spel("#{request.headers['foo'] == 'bar'}").to("direct:bar");
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Loading script from external resource
Available as of Camel 2.11
You can externalize the script and have Camel load it from a resource such as "classpath:", "file:", or "http:".
This is done using the following syntax: "resource:scheme:location", eg to refer to a file on the classpath you can do:
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.setHeader("myHeader").spel("resource:classpath:myspel.txt")
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Dependencies
You need Spring 23.7 0 or higher to use Spring Expression Language. If you use Maven you could just add the following to your pom.xml:
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