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Calling Overridden methods and overshadowed variables

 
Stephen Joseph
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Why is there difference between calling the overidden methods and overshadowed variables based on the object type(class) and reference (as stated in the book of Khalid )
 
Tanveer Rameez
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hi
I am not sure what you mean.But if you mean something that involves the code:
<code>
class Base{
String str="in Base";
void amethod()
{ system.out.println("in Base");

}
}
clas Sub extends base{
String str="in Sub";
void amethod()
{
System.out.println("In Sub");
}
}
class test{
public static void main(String args[])
{
Base b;
Sub s=new Sub();
b=s;
s.amethod();
System.out.println(s.str);
b.amethod();
System.out.println(b.str);
}

}
}
</code>
the output is: in Sub //amethod of Sub invoked by s
in Sub //varaible str of Sub accessed by s
in Sub //amethod of Sub invoked by b
in Base //varaible str of Base accessed by b
So the method called depends on the object, not on the object reference . Here the object reference of type Base points to an object of type Sub. So method amethod of class Sub is invoked.But variables accessed depends on the object reference.Since the object reference is of type Base, the variable 'str' of the Base class is accessed.
I hope this is what you wanted to know
regards
Tanveer
 
Stephen Joseph
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Thank you Tanveer.You guessed my Q right, but if you can tell me what is the reason for this difference why cant overridden methods and overshadowed variables be called in the same way.
 
Ajith Kallambella
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Since this topic is not concerned with Threads and Synchronization, I am moving it to a more appropriate forum - Java in General(intermediate). Please continue the discussion there.
Thanks!
Ajith
 
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