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code has an error please help

Gaurav Pavan Kumar Jain
Ranch Hand

Joined: Mar 19, 2007
Posts: 168
hi

please find the code as below: -

File---> Typ.java

code:-

public class Typ
{
int i=0;
public static void main(String args[])
{
System.out.println(i);
}
}


FIle:----> RefOpt.java

code: -

public class RefOpt
{
int x,y;
public static void main(String args[])
{
RefOpt acc =new RefOpt();
Typ obj=new Typ();

obj.i=100;
acc.x=100;

if(obj==acc) //1
{
System.out.println("Same Object belonging");
}
else
{
System.out.println("NOt Same Object belonging");
}

if (obj.equals(acc)) // 2
{
System.out.println("Equals");
}
else
{
System.out.println("Not Equals");
}
}
}

here //1 genrates the error Incomparible type.
//2 genrates the output "not equals".

Why is it happing.The values are equal & both are from different objects

Please correctthe code.
Barry Gaunt
Ranch Hand

Joined: Aug 03, 2002
Posts: 7729
The values are equal & both are from different objects


What values?
What do you think you are comparing on line 1?


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megha joshi
Ranch Hand

Joined: Feb 20, 2007
Posts: 206
For the == operator to work ... I think the two objects compared must be of same type or must belong to the same hierarchy .

Here your two object reference variables are vastly different and neither reference type extends the other , so theres no way both reference variables can refer to same object(== tests if they refer to same object). Hence == cannot be applied.
Kevin Liu
Greenhorn

Joined: Mar 17, 2007
Posts: 10
File---> Typ.java

code:-

public class Typ
{
int i=0;//static int i = 0;
public static void main(String args[])
{
System.out.println(i); //or System.out.println(new Typ().i);
}
}
 
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