Interface question

[Jacky Luk]

interface IReader<T>
{
     public T GetData();
}

class CSmartCard implements IReader<CTimeRec>
{
    public CTimeRec GetData()
	{
	    return buff;
	}
	
	public getOtherData()
	{
	}
	
	CTimeRec buff;
}

class CMainController
{
     public void MainController()
	 { 
	     List<CTimeRec> rec;
	     CTimeRec rec = cardReader.getData();
		 
		 OtherData otherData = cardReader.getOtherData();
		 
	 }
	 
	 
	 private CSmartCard cardReader;
	 // private IReader<CTimeRec> cardReader;
}

If I define cardReader as CSmartCard, I can make use of getOtherData();
if I define cardReader as IReader<CTimeRec>, can I make use of getOtherData();
If not, What should it be defined it as?
Thanks
Jack

[Winston Gutkowski]

Jack Luk wrote:If I define cardReader as CSmartCard, I can make use of getOtherData();

Yes.

if I define cardReader as IReader<CTimeRec>, can I make use of getOtherData();

No.

If not, What should it be defined it as?

That's entirely up to you; but given your code, I'd say probably a CSmartCard.

BTW: The use of initial 'I' and 'C' for your class/interface names is very old-fashioned. Maybe your course uses this notation, but you won't see it used often in the outside world (except perhaps in the Microsoft miniverse); and personally I find that it affects readability.

Winston

[Matthew Brown]

Winston Gutkowski wrote:(except perhaps in the Microsoft miniverse)

Even there they only use the I prefix for interfaces. They don't use anything for concrete classes. (I found the 'I's a bit jarring at first, but you get used to it. The one that throws me swapping between C# and Java is List, which is an interface in Java and a concrete class in .NET).

[Winston Gutkowski]

Matthew Brown wrote:The one that throws me swapping between C# and Java is List, which is an interface in Java and a concrete class in .NET).

Ooof. Yes, I can imagine.

@Jack: I also notice that your program won't compile. You call cardReader.getData(), but in your entities it's defined as GetData().
Methods in Java should start with a lowercase letter.

Winston