interface

[hemamalini s.]

public class Test6 implements I{
int k = 1;
public static void main(String args[]){
System.out.println(k);
}
}
interface I{
int k = 0;
}
What will be the output?
A1) 0
A2)1
A3)null
A4)Compiler Error
#####################################333
the answer is [4]
How?

[Saurabh Chaubey]

Hi hemamalini s.,
You cannot access a non-static member in a static context.
If you want to access the variable "k" in the interface I then you would have to use this:
System.out.println(I.k);

You can access "k" of interface I in the above manner as member variables of an interface are implicitly public static final.

Regards,
Saurabh

[Joseph Clark]

My compiler, javac 1.4.2, gives an error when asked to "System.out.print(l.k)".
I can comment out the instance variable, in which case "System.out.print(k)" prints "0", or I can create an instance of the class in "main()", call it "I", and "System.out.print(I.k)" prints "1". So, I would say the correct answer, in 1.4, is "Compiler Error".

[Saurabh Chaubey]

Hi Michael,
I am also mentioning that answer to question posted would be "Compile time error". But to access the variable k of the interface the following code will work:

public class Test6 implements I{
int k = 1;
public static void main(String args[]){
System.out.println(I.k);
}
}
interface I{
int k = 0;
}

//Output:0

[Joseph Clark]

Yes, you are right. I mistook the uppercase "I" for a lowercase "l".
"System.out.print(I.k)" prints "0".

[Kishore Dandu]

It sure is a tricky quesion. Thanks for posting.