Eclipse Community Forums: TMF (Xtext) » Easy way to get cross references?

Help

Home

Home » Modeling » TMF (Xtext) » Easy way to get cross references?

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

Easy way to get cross references? [message #894484]

Mon, 09 July 2012 11:58

Hannes Müller

Messages: 24
Registered: June 2012

Junior Member

Hi everyone,

I am working on the validation of my xtext model. Right now I want to check if "I am an original entity" and if so: I want to check if there are cross references in my actually model which reuse "me" (and check those cross references for identical feature values ...). For better understanding: This could e.g. happen in rules like the following:
Recalculate:
userStates += [SupportedUserState] ...
;

Do I have to iterate through all parts of the model which could contain those cross references and check for identical pointer adresses? Or is their a more easy approach?

I just tried out the method eCrossReferences() because of the name but it seems not to be the right method (the docu isn't that big for this method though)...

I would be greateful for any answer
Hannes

[Updated on: Mon, 09 July 2012 12:11]

Report message to a moderator

Re: Easy way to get cross references? [message #894495 is a reply to message #894484]

Mon, 09 July 2012 12:37

Henrik Lindberg

Messages: 2509
Registered: July 2009

Senior Member

You can get all references from the index maintained by the Xtext "all
state" / builder. This is preferred over getting the references as
pointers as this requires a resolution of the resources (you may end up
with all your resources being in memory).

The index tracks all exported and imported elements.

Regards
- henrik

On 2012-09-07 13:58, Hannes Müller wrote:
> Hi everyone,
>
> I am working on the validation of my xtext model. Right now I want to
> check if "I am an original entity" and if so: I want to check if there
> are cross references in my actually model which reuse "me" (and check
> those cross references for identical feature values ...). For better
> understanding: This could e.g. happen in rules like the following:
> Recalculate:
> userStates += [SupportedUserState] ...
> ;
>
> Do I have to iterate through all parts of the model which could contain
> those cross references and check for identical pointer adressses? Or is
> their a more easy approach?
>
> I just tried out the method eCrossReferences() because of the name but
> it seems not to be the right method (the docu isn't that big for this
> method)...
>
> I would be greateful for any answer
> Hannes

Report message to a moderator

Re: Easy way to get cross references? [message #894510 is a reply to message #894484]

Mon, 09 July 2012 13:44

Hannes Müller

Messages: 24
Registered: June 2012

Junior Member

Thx Hendrik for the answer Smile

,

Where can I find an example how to use this "all state" / builder? If I google this key words or search in the forum or in the xtext documentation - there are no good hits.

Thx for any answer
Hannes

Report message to a moderator

Re: Easy way to get cross references? [message #894557 is a reply to message #894510]

Mon, 09 July 2012 15:14

Henrik Lindberg

Messages: 2509
Registered: July 2009

Senior Member

On 2012-09-07 15:44, Hannes Müller wrote:
> Thx Hendrik for the answer :),
>
> Where can I find an example how to use this "all state" / builder? If I
> google this key words or search in the forum or in the xtext
> documentation - there are no good hits.
>
> Thx for any answer Hannes

It goes something like:

/**
* Access to the global index maintained by Xtext, is made via a
* special (non guice) provider
* that is aware of the context (builder, dirty editors, etc.). It is
* used to obtain the
* index for a particular resource. This special provider is obtained
* here.
*/
@Inject
private org.eclipse.xtext.resource.impl.ResourceDescriptionsProvider
indexProvider;

IResourceDescriptions descriptionIndex =
indexProvider.getResourceDescriptions(scopeDetermeningResource);
IResourceDescription descr =
descriptionIndex.getResourceDescription(scopeDetermeningResource.getURI());

i.e. you will get an instance of IResourceDescriptions that can answer
all sorts of index/resource related questions.

The actual implementation is naturally bound using guice and may be the
"all state" one inside the IDE, or some other provider when using Xtet
stand alone. The logic above stays the same.

The snippet is from the class
org.cloudsmith.geppetto.pp.dsl.linking.PPFinder found in cloudsmith /
geppetto @ github. You may want to look at it to get some inspiration
for how to search for things in the index.

Hope that helps.

- henrik

Report message to a moderator

Re: Easy way to get cross references? [message #894744 is a reply to message #894557]

Tue, 10 July 2012 10:48

Hannes Müller

Messages: 24
Registered: June 2012

Junior Member

Hi Hendrik,

Thanks for the hints Smile

. I looked into the file and try to understand what happens their.

Than I copy and pasted the result and tried to debug through it. It is a little bit hard to get to know what to deliver those methods without tutorial. But ok - right now I collect the things which I need by going through the model with eContainer() calls, but I keep this option in mind if I get performance problems.

So thanks again, the thread can be closed
Hannes

Report message to a moderator