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Question on Overriding

 
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Hi,
We know that the private methods are not overridden.
Then how does the following code compile
class R {
private void printS1(){System.out.print("R.printS1 ");}//1
protected void printS2() {System.out.print("R.printS2 ");}
protected void printS1S2(){printS1();printS2();}
}
class S extends R {
private void printS1(){System.out.print("S.printS1 ");}//2
protected void printS2(){System.out.print("S.printS2 ");}
public static void main(String[] args) {
new S().printS1S2();
}}

We say that the method printS1 is not overriden. Then what is happening in the above code?
-Sanjana
 
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S1 is a different method which happens to be the same method name in its superclass.
 
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Private access modifier makes a method implicitly final, which means it cannot be overridden. A private method of a superclass can be redeclared and redefined in its subclasses.
[ December 17, 2003: Message edited by: Vad Fogel ]
 
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I think of overriding as making a method more specific for the subclass.
Think of the subclass taking the method from it's superclass and improving it. But if that method is private in the superclass it does not exist for the subclass, it's totally invlsible.
 
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In javaworld article "Private and final?"
 
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That's a good article.... Thanks surasak...
Private method and final works differently and treated differently by the JVM.... And one more interesting thing is that combination of both keywords "private" and "final" is treated differently again....
I can say that the article is good to read to know details about the "private" and "final" keywords...
 
sanjana narayanan
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Thank u everyone for replying.
I was expecting the same answer but in one of the certification guide by Simon Roberts/Barry Boone(not sure which author it was), they had specified that private methods can be overriden by private/default/protected/public methods. That's why i wanted to reconfirm things.
-Sanjana
 
Ko Ko Naing
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Originally posted by sanjana narayanan:
Thank u everyone for replying.
I was expecting the same answer but in one of the certification guide by Simon Roberts/Barry Boone(not sure which author it was), they had specified that private methods can be overriden by private/default/protected/public methods. That's why i wanted to reconfirm things.
-Sanjana


I used that book, when i took SCJP1.2... I'm not sure whether they said so... Did u read that part carefully? I mean if they r talking about it another context... That kind of mistake is not for authors like them...
 
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