Eclipse Community Forums: TMF (Xtext) » Serialization of Xtext model

Help

Home

Home » Modeling » TMF (Xtext) » Serialization of Xtext model

Show: Today's Messages :: Show Polls :: Message Navigator

Serialization of Xtext model [message #1796185]

Mon, 08 October 2018 06:31

Venkata Chittem

Messages: 13
Registered: October 2018

Junior Member

Hi,
I would like to convert xmi file to myDSL file.

Please help me with some examples and relevant information on classes/methods to be implemented in xtext plugins to achieve this.

Best Regards,
Venkata

Report message to a moderator

Re: Serialization of Xtext model [message #1796186 is a reply to message #1796185]

Mon, 08 October 2018 06:42

Christian Dietrich

Messages: 14665
Registered: July 2009

Senior Member

hi, simply and your root eobject to a mydsl resource and call resource.save

Twitter : @chrdietrich
Blog : https://www.dietrich-it.de

Report message to a moderator

Re: Serialization of Xtext model [message #1796192 is a reply to message #1796186]

Mon, 08 October 2018 08:08

Tamas Miklossy

Messages: 157
Registered: February 2016

Senior Member

Report message to a moderator

Re: Serialization of Xtext model [message #1796226 is a reply to message #1796192]

Mon, 08 October 2018 13:58

Venkata Chittem

Messages: 13
Registered: October 2018

Junior Member

Hi,
Searching on Xtext forum, i found what i was doing wrong: https://www.eclipse.org/forums/index.php/t/794171/
Xtext project nature is missing in the plugin where I call XtextResource.save(null).

However, I am getting a different error now.
java.lang.RuntimeException: A value for feature 'myERefContained' is missing but required.
Semantic Object: myEClass
URI: file:/F:/MyPrj/MyFile.mydsl

I have checked the Emf Object Tree in the DSLResource before calling save and found that myERefContained is set with a instance value of respective EClass EObject.

Report message to a moderator

Re: Serialization of Xtext model [message #1796230 is a reply to message #1796226]

Mon, 08 October 2018 14:22

Christian Dietrich

Messages: 14665
Registered: July 2009

Senior Member

can you provide a minimal resproducing example incl. unit test.

Twitter : @chrdietrich
Blog : https://www.dietrich-it.de

Report message to a moderator

Re: Serialization of Xtext model [message #1796232 is a reply to message #1796226]

Mon, 08 October 2018 14:26

Ed Willink

Messages: 7655
Registered: July 2009

Senior Member

Hi

Familiar problem. In my experience the Xtext serialization failure message is very detailed but difficult to understand. With hindsight I think I usually agree that it is correct. I suspect that you may have a myERefContained where you looked, but probably you do not have it where Xtext complains.

I find that it is usually necessary to set a breakpoint on the Xtext serialization diagnostic, and in some cases to perform an XMI save just beforehand to provide a reference for the Xtext message. But beware, the XMI save should match the Resource you are debugging, but your problem may be due to a bit of magic/lazy code that corrupts what Xtext serializes.

Regards

Ed Willlnk

Report message to a moderator

Re: Serialization of Xtext model [message #1796240 is a reply to message #1796232]

Mon, 08 October 2018 16:25

Venkata Chittem

Messages: 13
Registered: October 2018

Junior Member

I have analyzed further! I found below function in myDSLSemanticSequencer.java which is raising the error i am getting.
Actually it could find the EFeature that it is looking for in the EObject, but in the .ecore this feature is set Transient so it is logging the error in createFeatureValueMissing() and is exiting all the way out of Resource.save() call.

After further searching with keywords "Xtext Serialize Transient", I found this thread https://www.eclipse.org/forums/index.php/t/1079269/, in which Christian Dietrich had answered (in 2009 :-) ) it that one can implement ITransientValueService to tell xtext that what to do with transient values.

Thanks a lot! I will try this tomorrow.

----------------------------

protected void sequence_myEClass(ISerializationContext context, myEClass semanticObject) {
if (errorAcceptor != null) {
if (transientValues.isValueTransient(semanticObject, myXmiPackage.eINSTANCE.getmyEClass_myERefContained()) == ValueTransient.YES)
errorAcceptor.accept(diagnosticProvider.createFeatureValueMissing(semanticObject, myXmiPackage.eINSTANCE.getmyEClass_myERefContained()));
}
SequenceFeeder feeder = createSequencerFeeder(context, semanticObject);
feeder.accept(grammarAccess.getmyEClassAccess().getmyERefContainedmyERefContainedParserRuleCall_1_0(), semanticObject.getmyERefContained());
feeder.finish();
}

SequencerDiagnosticProvider.class

@Override
public ISerializationDiagnostic createFeatureValueMissing(EObject semanticObject, EStructuralFeature feature) {
String msg = "A value for feature '" + feature.getName() + "' is missing but required.";
return new SerializationDiagnostic(FEATURE_VALUE_MISSING, semanticObject, grammarAccess.getGrammar(), msg);
}

Report message to a moderator

Previous Topic:	Using Formatter2
Next Topic:	XText Binding Generators from another Project

Goto Forum:

-=] Back to Top [=-

[ Syndicate this forum (XML) ] [

]

Current Time: Thu Apr 25 04:35:29 GMT 2024

.:: Contact :: Home ::.

Breadcrumbs

Sign up to our Newsletter