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Explanation Required

 
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Can anybody explain that why it produce the output 10050 why noy not 10010
?

class Valhold{
public int i=10;
}
public class Obparam {
public static void main(String s[]){
Obparam o=new Obparam();
o.amethod();
}
public void amethod(){
int i =99;
Valhold v=new Valhold();
v.i=30;
another(v,i);

System.out.println(v.i);
}
public void another(Valhold v,int i)
{
i=0;
v.i=50;
Valhold vh=new Valhold();
v=vh;
System.out.println(v.i);
System.out.println(i);
}
}
 
Ranch Hand
Posts: 242
Mac Java Ubuntu
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Hi AtulKumar Gaur

It's because

1.public void amethod(){
2.int i =99;
3.Valhold v=new Valhold();
4.v.i=30;
5.another(v,i);
6.
7.System.out.println(v.i);
8.}

v is still pointing to the object created at line 3

And for that you have chnged value in method another() by using its reference copy.. i.e. in line 4 in below snippet

1.public void another(Valhold v,int i)
2.{
3.i=0;
4.v.i=50;
5.Valhold vh=new Valhold();
6.v=vh;
7.System.out.println(v.i);
8.System.out.println(i);
9.}

That's why you are getting 50 not 10 for line 7 in method amethod()..

Regards..
 
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Because in java even the references are actually passed by value.

"Valhold v" in "amethod()" and Valhold v in "another()" are two different references to the same object, and that "Valhold v" parameter in function "another()" is a reference which remains local to the function.
 
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Hi,

If this link could help:

Pass By Value & Pass By Reference


Thanks,
 
Don't get me started about those stupid light bulbs.
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