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Class Cast exception thrown for an EMap during model instantiation [message #1053441]

Sun, 05 May 2013 22:20

Greg Mising name

Messages: 47
Registered: July 2009

Member

I have implemented a reference to a class that I've assigned an instance class name of java.util.Map$Entry, thus using it as an EMap. When I start my editor and run through the wizard it instantiates the model and assigns the root object to the xml serialization object. In doing so it iterates through a tree of all the contents of the model from the root object. This is in the method ResourceImpl.attached( EObject ). The code progresses down to EContentsEList.hasNext() where the following code is called.

else
                  {
                    @SuppressWarnings("unchecked") InternalEList<E> newValueList = (InternalEList<E>)value;
                    valueList = valueInternalEList = newValueList;
                  }

Here the value that is being cast as an InternalEList is the EBasicMap implementation of my Map$Entry reference. This is where it is throwing a class cast exception.

Am I doing something wrong in my design or code or is this a bug in EMF?

Thanks.
Greg

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Re: Class Cast exception thrown for an EMap during model instantiation [message #1053457 is a reply to message #1053441]

Mon, 06 May 2013 05:56

Ed Merks

Messages: 33140
Registered: July 2009

Senior Member

Greg,

On 06/05/2013 12:20 AM, Greg Mising name wrote:
> I have implemented a reference to a class that I've assigned an
> instance class name of java.util.Map$Entry, thus using it as an EMap.
What does it's generated implementation look like? Is the reference a
multi-valued containment?
> When I start my editor and run through the wizard it instantiates the
> model and assigns the root object to the xml serialization object. In
> doing so it iterates through a tree of all the contents of the model
> from the root object. This is in the method ResourceImpl.attached(
> EObject ). The code progresses down to EContentsEList.hasNext() where
> the following code is called.
>
>
> else
> {
> @SuppressWarnings("unchecked") InternalEList<E>
> newValueList = (InternalEList<E>)value;
> valueList = valueInternalEList = newValueList;
> }
>
>
> Here the value that is being cast as an InternalEList is the EBasicMap
> implementation of my Map$Entry reference. This is where it is
> throwing a class cast exception.
>
> Am I doing something wrong in my design or code or is this a bug in EMF?
It works for Ecore's EStringToStringMapEntry EClass, so you must have
done something slightly different
>
> Thanks.
> Greg

Ed Merks
Professional Support: https://www.macromodeling.com/

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Re: Class Cast exception thrown for an EMap during model instantiation [message #1053548 is a reply to message #1053457]

Mon, 06 May 2013 13:21

Greg Mising name

Messages: 47
Registered: July 2009

Member

Hi Ed,

Yes, it's a multi-valued containment. I've attached a screenshot of the model objects. LocaleStringMap has an instance class name of java.util.Map$Entry, so the three references are implemented as EMaps.

The three references are initialized as follows:

protected NamedModelObjectImpl() {
		super();
		localeName = new BasicEMap<String,String>();
		localeDescription = new BasicEMap<String,String>();
		localeTooltip = new BasicEMap<String,String>();
	}

Thanks for your help.

Cheers,
Greg

Attachment: Screen Shot 2013-05-06 at 6.15.48 AM.png
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Re: Class Cast exception thrown for an EMap during model instantiation [message #1053563 is a reply to message #1053548]

Mon, 06 May 2013 14:32

Ed Merks

Messages: 33140
Registered: July 2009

Senior Member

Greg,

Comments below.

On 06/05/2013 3:21 PM, Greg Mising name wrote:
> Hi Ed,
>
> Yes, it's a multi-valued containment. I've attached a screenshot of the model objects. LocaleStringMap has an instance class name of java.util.Map$Entry, so the three references are implemented as EMaps.
>
> The three references are initialized as follows:
>
> protected NamedModelObjectImpl() {
> super();
> localeName = new BasicEMap<String,String>();
> localeDescription = new BasicEMap<String,String>();
> localeTooltip = new BasicEMap<String,String>();
You hand wrote this? Generated implementations would use EcoreEMap, so
this doesn't look generated.
> }
>
>
> Thanks for your help.
>
> Cheers,
> Greg

Ed Merks
Professional Support: https://www.macromodeling.com/

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