The constant language is a trivial built-in language that is used to specify a plain text string. This makes it possible to provide a plain text string in any context where an expression type is expected.
The code shown in Example 1, “Using the constant language” sets the username
header to the value Jane Doe
.
Example 1. Using the constant language
<camelContext> <route> <from uri="SourceURL
"/> <setHeader headerName="username"> <constant>Jane Doe</constant> </setHeader> <to uri="TargetURL
"/> </route> </camelContext>