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why not nullpointer exception?

saikrishna cinux
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Joined: Apr 16, 2005
Posts: 689


hi here getMyClass is returning null but it is not throwing nullpointer exception ?

why?


A = HARDWORK B = LUCK/FATE If C=(A+B) then C=SUCCESSFUL IN LIFE else C=FAILURE IN LIFE
SCJP 1.4
Neelesh Bodas
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Joined: Jul 20, 2006
Posts: 107
because myName is a static member of the class. The fact that java allows you to reference a static member using the instance of the class is simply a syntactic sugar, it doesnot use the instance reference to retrive the value of the member
[ August 23, 2006: Message edited by: Neelesh Bodas ]
Gowher Naik
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Joined: Feb 07, 2005
Posts: 643


Check code above
Run above code as it is and see output
Remove static keyword at line 2 and run above code and see output
Kaush Kane
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Joined: May 22, 2006
Posts: 37
public class returnNull{
static String myName="SCJP"; //line 2
public static void main(String args[]){
returnNull r1=new returnNull();
r1=null;
System.out.println(r1.myName);
}
}


I tried running the above code. I m getting the o/p as "SCJP" and not Null pointer exception. Could you explain me why???
Jon Lee
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Joined: Mar 04, 2005
Posts: 134
Neelesh Bodas has already given the answer......


SCJP 5.0 - 98% (2007)<br />SCWCD 1.4 - 97% (2007)
Gowher Naik
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Joined: Feb 07, 2005
Posts: 643

As we know static variables or static methods can be executed by class
name also so The compiler replaces line System.out.println(r1.myName);
as System.out.println(returnNull.myName); this is why there is no null
point exception.
Check the code above
 
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