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class ValHold{
public int i = 10;}
public class ObParm{
public static void main(String argv[]){
ObParm o = new ObParm();
o.amethod(); }
public void amethod(){
int i = 99;
ValHold v = new ValHold();
v.i=30;
another(v,i);
System.out.print( v.i ); }//End of amethod

public void another(ValHold v, int i){
i=0;
v.i = 20;
ValHold vh = new ValHold();
v = vh;
System.out.print(v.i);
System.out.print(i); }//End of another}
1) 10030
2) 20030
3) 209930
4) 10020

i dont understand how to solve this problem?
 
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Starting from main method:

object of obparm is created and reference is stored in o.
amethod with reference of o is called.

Execution os amethod:
i = 99.
Creates object of ValHold and saves object reference in v.
Sets value of i in v to 30.
calls another method passes parameters as 1. v created as above with value 30 and 2. i (= 90).

Execution os another:
Gets parameters in local variable v and i respectively.
set value of local variable i to 0.
sets value of i in object v to 20.
creates new object of VahHold and assigns it to variable vh.
local variable v is reassigned to new reference of vh.
System.out.print(v.i) will print reassigned value of local variable that is - 10
System.out.print(i) will print local value of i that is 0
System.out.print( v.i ) will print actual value changed by statement "v.i = 20" = 20.
so, it is 10 0 20
 
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