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Default constructor

Priyanka Chopda
Ranch Hand

Joined: Jul 22, 2003
Posts: 112
Hi,

I think the answer should be d, but correct ans is c??
I was under impression that if you have argumented construtor you "must" also have default construtor defined, since it is provided implicitly.
Any missing part for me?
Advannce Thanx
-PC
Priyanka Chopda
Ranch Hand

Joined: Jul 22, 2003
Posts: 112
sorry...I missed "not" part in sentence
--since it is not provided implicitly if you have any other constructor.
-PC
Kalai Ganesh
Ranch Hand

Joined: Sep 08, 2003
Posts: 32
Hai Priyanka,
The answer is c. Your assumption (answer d) would have been correct if the Bclass constructor did not call super(3).
Say, the Bclass constructor has simply been omitted or has nothing in its body, then a no-argument super class constructor would have been called by default as you said.

The choice would be d for this case :
class AClass {
static int x;
AClass(int x) { this.x = x; }
}
public class BClass extends AClass {
BClass() {} // or if this line has been commented out.
public static void main(String[] args) {
BClass BC = new BClass(); System.out.println(x);
}
}
Hope this helps.
Kalai Ganesh
Ranch Hand

Joined: Sep 08, 2003
Posts: 32
Even for this case you'll get a compile time error because there is no constructor in Aclass that accepts no arguments.
BClass() { super(); }
In your program, you are safe since a matching super class constructor is called in Bclass constructor.
[ October 15, 2003: Message edited by: Kalai Ganesh ]
Vinod Sinha
Ranch Hand

Joined: Oct 16, 2003
Posts: 43
The answer is (c) because there is no default
constructor created for A and B calls the constructor
with argument which is perfectly fine!
Priyanka Chopda
Ranch Hand

Joined: Jul 22, 2003
Posts: 112
thanks buddies!
That helped
-PC
chang Anne
Greenhorn

Joined: Jul 02, 2003
Posts: 29
Hello,
I have a question that is a subclass can extends a static variable
from superclass?
I know a static variable is shared by all object, but it can share by an instance of subclass?

I am really appreciate it.
 
 
subject: Default constructor
 
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