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Implementing interfaces

 
Greenhorn
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Hi there

the first chapter's two-minute drill (SCJP5, page 69) states at Interface Implementation, bullet #2:

"Interfaces can be implemented by any class, from any inheritance tree."

I think this is correct only if interfaces are declared as public. You can have a default interface as well, which is not visible by a class from a different package.

Am I right?

thanks,
Septimiu
 
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Originally posted by septimiu pelau:
Hi there

the first chapter's two-minute drill (SCJP5, page 69) states at Interface Implementation, bullet #2:

"Interfaces can be implemented by any class, from any inheritance tree."

I think this is correct only if interfaces are declared as public. You can have a default interface as well, which is not visible by a class from a different package.

Am I right?

thanks,
Septimiu


Yes. You have to take access privileges into account.
 
Septimiu Pelau
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Then it's a good candidate for the errata, but that post was locked one year ago.
 
Ranch Hand
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Hi,

Interfaces are by dedault public and abstract.

So any where you can implement them even outside the package also
 
Septimiu Pelau
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You are confusing the access modifiers of interface methods with interfaces. While interface methods are indeed public and abstract implicitly the interfaces are only abstract. Therefore an interface can have the default access modifier (for this reason it must be declared within the same file with a public class or interface)
 
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You are right Sepitmul
 
Septimiu Pelau
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Thank you Virtank
 
Vikrant Sahdev
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You got my name wrong. I realized that I did that as well for you.
Hope you get it right now.
 
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