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Constructor

 
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Hi,

A class which has all its constructors declared as private

1. Cannot be instantiated by any other class.
2. Cannot be extended.
3. Both i and ii.
4. has to be declared final.

What should be the correct options? I thought the answer was 1 but it said that it was 3.

Thanks
 
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A subclass constructor by default call no arg constructor of superclass but since superclass constructor is private it wont work.
 
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Yes, You can't extend a class that has declared all its constructors as private.

Because any class extending it should call its super class constructor and this will cause error as sub class cannot access private members of super class.

Look at .Corey Tips for more explanation..

Thanks,
Raja
 
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I think The correct answer is 1 and 3.

How can the subclass call the private member of the super class.
 
Greenhorn
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The correct answer is 2.

you can instaniate the class by having a static method which makes a call to private constructor(just like singleton pattern).
 
Pradeep bhatt
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Originally posted by Surendra Kumar:
The correct answer is 2.

you can instaniate the class by having a static method which makes a call to private constructor(just like singleton pattern).



As per you statment, 1 is also a answer. You forgot to metion it.
[ January 13, 2005: Message edited by: Pradeep Bhat ]
 
Surendra Kumar
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thanks for correcting it
 
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Originally posted by shri mon:
I think The correct answer is 1 and 3.



Um, interesting choice of The correct answer.
 
Puja S
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Thanks to all..... so the answer is 3
 
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You can still have an inner class extends an outer class with all contructor being private. So the answser is 1. Is it a bad question?
 
Barry Gaunt
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Originally posted by Jack Zhou:
You can still have an inner class extends an outer class with all contructor being private. So the answser is 1. Is it a bad question?



That's a counter!


 
Barry Gaunt
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I guess they were not thinking about that possibility.
 
Greenhorn
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who can tell me the putting out ,and tell me exactly?
 
Java Cowboy
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Puja S, please check your private messages. You can see them by clicking My Private Messages.
 
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