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Connection con;

 
Greenhorn
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Hai members,
First of all thanking you to all of members to sending response to
my previous doubts.

actually Connection is a interface but we can write in this way

Connection con;
interface we cant create object;
 
Ranch Hand
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And the question is?
 
Ranch Hand
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Connection is an interface.With a reference of type Connection you would actually point to an implementation of Connection interface.
 
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Connection con;
interface we cant create object;

You are not creating an object in this statement,
You are declaring a variable con that can later hold an object that implements the interface Connection.

Later in your code, you will not use: con = new Connection(), but something else.
What are you doing: you are asking your database driver to give you an object that implements the Connection interface.

It's a good idea to set a breakpoint in this line of code, and see what class this object actually is.

Regards, Jan

[corrected my typo: Connection class - doh]
[ August 27, 2007: Message edited by: Jan Cumps ]
 
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