Chapter 67. Constant Language
Chapter 67. Constant Language Available as of Camel version 1.5 The Constant Expression Language is really just a way to specify constant strings as a type of expression. Note This is a fixed constant value that is only set once during starting up the route, do not use this if you want dynamic values during routing. 67.1. Constant Options The Constant language supports 1 options, which are listed below. Name Default Java Type Description trim true Boolean Whether to trim the value to remove leading and trailing whitespaces and line breaks 67.2. Example usage The setHeader element of the Spring DSL can utilize a constant expression like: <route> <from uri="seda:a"/> <setHeader headerName="theHeader"> <constant>the value</constant> </setHeader> <to uri="mock:b"/> </route> in this case, the Message coming from the seda:a Endpoint will have 'theHeader' header set to the constant value 'the value'. And the same example using Java DSL: from("seda:a") .setHeader("theHeader", constant("the value")) .to("mock:b"); 67.3. Dependencies The Constant language is part of camel-core .
<route> <from uri="seda:a"/> <setHeader headerName="theHeader"> <constant>the value</constant> </setHeader> <to uri="mock:b"/> </route> from("seda:a") .setHeader("theHeader", constant("the value")) .to("mock:b");