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Strange question

Gitesh Ramchandani
Ranch Hand

Joined: Feb 28, 2007
Posts: 274
For the following code sample:

interface foo {
int k = 0;
}

public class test implements foo {
public static void main(String args[]) {
int i;
test t = new test();
i= t.k;
i= test.k;
i= foo.k;
}
}

What is the result?

A. Compilation succeeds.
B. An error at line 2 causes compilation to fail.
C. An error at line 9 causes compilation to fail.
D. An error at line 10 causes compilation to fail.
E. An error at line 11 causes compilation to fail.
Ans: A

Doubt: if I modify the code as
int i;
System.out.println(i);

test t = new test();
System.out.println(i);
i= t.k;

it gives compilation error �variable i might not have been initialized�.

Why is this so?

pls help
regards,
gitesh
Abdullah Mamun
Ranch Hand

Joined: Mar 19, 2007
Posts: 99

int i;
System.out.println(i);
...
it gives compilation error �variable i might not have been initialized�.

Why is this so?


You cannot use any local variable before initializing. But you can use instance variables without initializing because they are initialized by the default values.


MooN
Jesper de Jong
Java Cowboy
Saloon Keeper

Joined: Aug 16, 2005
Posts: 14074
    
  16

Note: Please quote your sources


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raghu nagabandi
Ranch Hand

Joined: Aug 14, 2007
Posts: 35
Interface variables are implecitly
public static final
Gitesh Ramchandani
Ranch Hand

Joined: Feb 28, 2007
Posts: 274
thanks for help.

The source of question is unknown, i found it in some materials (txt file) i downloaded from net.
 
 
subject: Strange question
 
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