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has-a and static variables

Joerg Waldmann

Joined: Mar 14, 2006
Posts: 17
In the K&B Book is the answer of Self Test Questin 1 in Chapter 2:
Has-a relationships always rely on instance variables.

And what is about class (static) variables. Isn't that a has-a relationship, too?

sandeep biradar

Joined: Mar 04, 2006
Posts: 4
please send correct question no.
Joerg Waldmann

Joined: Mar 14, 2006
Posts: 17
It's in the SCJP 310-055, self test chapter 2, Question no 1.
The wright answer ist B, has-a relationship always rely on instance variables.

I think, has-a relationship rely on class variables, too.
Arno Reper
Ranch Hand

Joined: Mar 14, 2006
Posts: 286
The static var exists before an instance is made...what object does have them, then? You can't have a Has-a relationships with the static var.
Im still studying maybe Im wrong but I dont think so.
I hope you understand what I mean...

The man who makes no mistakes does not usually make anything<br /> <br />>>> SCJP 5.0 >> SCJD B&S <<< In progress
Joerg Waldmann

Joined: Mar 14, 2006
Posts: 17
The definition of has-a in the book is: In Instance, that has a reference to the instance of another class.
So, in my opinion, a class variable is a reference to an instance, too. It's just the same instance for all objects of this class.
I agree. Here's the link:
subject: has-a and static variables
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