How can we invoke a Java UDF in XText Grammar?

Question

I am working on a DSL wherein I am supposed to call Java Functions I have written. How can they be called in XText Grammar definition rules ?

Example Sample.xtext Data: 'Data'':' (objectRules += ObjectRule)+ //Call to Java Function here ; I am writng the grammar and I want to invoke Java Function to perform further processing like pasting a block of code when the Rule is encountered.

Answer 1

Please refer to the documentation on Xbase if you want to use Java from your Xtext languages.

The pattern would be something like this:

grammar org.acme.MyDsl with org.eclipse.xtext.xbase.Xbase
generate ..
MyConcept:
  operation=ID '(' ')' body = XBlockExpression
;

This would allow things like

myOperation() {
  System.out.println("")
}