Re: Using Interfaces ?

"TonyB" <tonyb@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:dFcEh.6455$ud2.5085@xxxxxxxxxxxxxxxxxxxxxxxxx
I've started java recently and I'm having some problems using interfaces
in real world cases.
Say I have an interface, "exampleinterface" declaring a list of methods. I
write a class, "example1class" which implements the interface methods 1
for 1. I can compile the class ok since all methods required by the
interface are implemented in the class. I could write another class which
also implements interface "exampleinterface" called "example2class".

Now if I want to use an object of type "example1class" in my code, I
create it using "exampleobject = new example1class" where exampleobject is
declared as type "example1class". Similarly I could use "example2class"
also.

But I'm puzzled as to how to create an object that uses the interface
"interfaceexample", and how to specify which of the two possible classes
that implement the interface are actually used in my code ?

Thanks
Tony

I think I've answered my own question. An interface is really declaring a
type for a class's methods , so that when I use a class based on that
interface, it is type checked that it meets the requirements defined in the
interface ?
So I could say
exampleinterface object 1 ;
exampleinterface object 2 ;
....
object1 = new example1class();
object2 = new example2class();

If this compiles I know that both objects implement the required methods.
Do I understand this correctly ?
Tony


.

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