No instances can be created from abstract classes

Dear SAPGurus,
I have developed a oData Service in my backend system & able to register the service in the gateway hub system. When i try to execute the metadata of the service from gateway system i am able to see the metadata with list of entity types availble in the data model.
But when i try to execute with entity set i am getting the following error.
"The class 'ZCL_ZGRC_DATA_MODEL_DPC' is abstract. No instances can be created from abstract classes."
Where my data model provider class name is 'ZCL_ZGRC_DATA_MODEL_DPC'
Kindly help me.
Thanks & Regards,
Rumeshbabu S

Hello Rumesh,
I do not think the error which u are getting is because of System Alias setting in SPRO.
Its something else which is really strange.
However the below is the setting to be maintained in GW SPRO system alias when u have a environment setup like u have now.
I mean the way u have created service and registered -
In ECC system u have created service using builder.
In GW system u have registered it and trying to access now via an RFC destination.
We have the same setup like u have now and we do not have any issues. We have also maintained the System Alias like i have shared in screen shot.
Check your System Alias config once in SPRO. But i dont think this is causing problem in your case. Still check once.
As per my understanding, from GW its trying to hit the DPC class and hence i feel system alias setting is correct in your case.
Problem is something else which is really strange.
Check error logs and see if it can. Share the error log please.
Regards,
Ashwin

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>
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Regards
Marcin

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Please Help!!
PS: i have seen this kind of code many times. So i feel that I don't understand how its really the abstract methods are made.
PS2: I understand that obviously you don't do something like this: *"obj = new AbstractClass(); "*. I dont understand how it could be: ServerSocketChannel ssc = ServerSocketChannel.open(); and the compiler didn't warn.

molavec wrote:
ServerSocketChannel ssc = ServerSocketChannel.open(); //<--I have never thought do that!! Anyway, how it is static method may work.
The static method creates an instance of a class which extends ServerSocketChannel, but is actually another non-abstract class.I thought that, but reading the documentation I saw that about open() method:
Opens a server-socket channel.
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Ok, I speak Spanish by default (<-- this sounds like "I am a machine", ^_^' ). So, I didn't know how to say that the method would be {}. Is there a way to say that?? I recommendable for me to know, for the future questions o answers.Not sure what you're saying here. But the other respondent was trying to explain to you the difference between an abstract method and an empty method.
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No instances can be created from abstract classes

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