Spring Integration Java DSL - Http Outbound Gateway uri 变量表达式

Question

I have a Http Outbound Gateway where I want to set a uri variable with a value from a Message header. I can see that this can be done like so:

            .handle(Http
                    .outboundGateway(serviceUri, restTemplate)
                    .uriVariable("var", expression)
                    .httpMethod(HttpMethod.POST)

The expression is of type org.springframework.expression.Expression . How do I create such an Expression object for say a JmsHeaders.CORRELATION_ID value? I can't find any examples anywhere. I know that the String SPEL would be "headers['correlationId']" but I don't know how to turn that into an Expression object?

I am using spring-integration-java-dsl:1.1.0.RELEASE .

Answer 1

See this answer to a similar question .

Note that JmsHeaders.CORRELATION_ID is actually jms_correlationId . It's safer to use the constant...

PARSER.parseExpression("headers['" + JmsHeaders.CORRELATION_ID + "']");