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Has-a relationship

Stary Kapec
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Joined: Dec 04, 2005
Posts: 81
class A {}
class B extends A {}
class C { B b; }

C has-a B, but my doubt is if C has-a A is also true, because B extends A

Thanks
Gavin Tranter
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Joined: Jan 01, 2007
Posts: 333
I would have guessed that C HAS-A A, as B IS-A.
But the reference is actual to a class of type B, therefore I would say C dosnt HAVE-A A.

But that is just my guess, would like to know what others think
[ March 20, 2007: Message edited by: Gavin Tranter ]
Srinivasan thoyyeti
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Joined: Feb 15, 2007
Posts: 557
Yes. C has A through B, would be more proper.

There is difference in saying "C has A" and "C has A through B."

1)C has A: Here A's methods will work on its data.

2)"C has A through B." : when Method overriding takes place, "B method may include its own data too".

Hope its clear.


Thanks & Regards, T.Srinivasan
SCWCD 1.4(89%), SCJP 5.0(75%)
 
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subject: Has-a relationship