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Interface

 
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Hi,
Got a simple doubt!
Can we instantiate a interface?Is'nt it implicitly abstract?
CAN U WRITE LIKE THIS
Runnable a = new Runnable()
Thanx
 
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Hi Rajani,
You are correct that you cannot instantiate an interface or an abstract class.
If you attempt to, you will get a compiler error or an InstantiationError.
--liz
[This message has been edited by Elizabeth Lester (edited August 22, 2001).]
 
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Helo!
Interface must be implemented, in your case the minimal implementation is:
Runnable a = new Runnable() { public void run() { } };

------------------
Antti Barck
It Solutions Consultant -- NSD Oy
Sun Certified Programmer for the Java™ 2 Platform
 
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Originally posted by Antti Barck:
Helo!
Interface must be implemented, in your case the minimal implementation is:
Runnable a = new Runnable() { public void run() { } };


You cannot instantiate an interface
But there is a way to do it using anonymous class.Though its not exactly an instantiation, it is just that the anonymous class will have the name of the interface which it implements
[This message has been edited by Ragu Sivaraman (edited August 22, 2001).]
[This message has been edited by Ragu Sivaraman (edited August 22, 2001).]
 
Anonymous
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Helo Ragu, can't understand a word you say...
------------------
Antti Barck
It Solutions Consultant -- NSD Oy
Sun Certified Programmer for the Java™ 2 Platform
 
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Hi,
You cannot instantiate an interface because they are abstarct. In the code
Runnable r = new Runnable();
its not instantiating. You are simply creating an annonymouse class (new runnable());
Hope this helps,
Vidhya.
 
Anonymous
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Hi guys!
I remember myself saying: "Interface must be implemented"
Implementation is done in child class and the minimal implementation I showed, just happened to be anonymous.
Get it?
------------------
Antti Barck
It Solutions Consultant -- NSD Oy
Sun Certified Programmer for the Java™ 2 Platform
 
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Hi,

We can declare object references for the interface. These
object references can hold any instatnce of the class which
implements that interface. for eg.


Output:
This is from myclass1 10
This is from myclass2 20

The correct version of the method is called thru the obj ref.

Indu

[This message has been edited by INDU, BALA (edited August 23, 2001).]
[This message has been edited by INDU, BALA (edited August 23, 2001).]
 
Ragu Sivaraman
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Originally posted by Antti Barck:
Helo Ragu, can't understand a word you say...


I am sorry antti... I cant be more clearer than that
 
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when exception occer?
 
Don't get me started about those stupid light bulbs.
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