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Problem with Terminal rule INT in generator [message #757679]

Mon, 21 November 2011 04:04

Eclipse User

Hey,

I have a little Problem with my grammar and my generator. Maybe anyone of you knows a solution for this.

In my grammar I defined an optional int property:

Properties:
('weightX' weightX=INT)?

Now I like to check in my generator if the value is set or not. Int is a primitive Java type and cannot be null (only references can be). So the the property gets the default value 0 and I can do the following check in:

«IF (c.properties.weightX != 0)»

My Problem with this check is that my property can't have the value 0 and this should be allowed. Is there any Solution for this? Is there any possibility that my generator uses Integer instead of int?

Best regards,
Simon

Re: Problem with Terminal rule INT in generator [message #757682 is a reply to message #757679]

Mon, 21 November 2011 04:08

Eclipse User

You could also do

(hasWeightX ?= 'weightX' weightX=INT)?

Then you have an additional boolean property "hasWeightX" which you can query if your hole block is present in the model.

«IF (c.properties.hasWeightX)»
«do something with c.properties.weightX ...»

Kind regards,
Ingo

Re: Problem with Terminal rule INT in generator [message #757683 is a reply to message #757679]

Mon, 21 November 2011 04:10

Eclipse User

You can use Ecore's EObject#eIsSet method: c.properties.eIsSet(c.properties.eClass.getEStructuralFeature("weightX"))
(It's fairly easy to wrap this in a nice extension.)

Re: Problem with Terminal rule INT in generator [message #757689 is a reply to message #757679]

Mon, 21 November 2011 04:17

Eclipse User

Thanks for the quick response! Smile