CODEWITHSUNDEEP
javaannotations
Some Guy
Some Guy

Reputation: 13568

Can there be Java interfaces that aren't annotations?

I see that @Interface is used to declare an annotation. Can @Interface be used to declare something other than an annotation as well?

If not, why not just call it @Annotation or something?

Upvotes: 0

Views: 56

Answers (2)

Stephen C
Stephen C

Reputation: 718886

I see that @Interface is used to declare an annotation.

Actually, it is @interface and the distinction is important; see your other Question.

If not, why not just call it @Annotation or something?

  1. Because they didn't.

  2. Because Annotation would violate the style rules (as an identifier)

  3. Because annotation was not reserved as a keyword. Turning it into a keyword would potentially make lots of existing customer Java code non-compilable.

    (That is what they did with enum and it caused problems for some people. It would cause more problems in this case ... because the amount of existing legacy Java code has grown in the last ~15 years.)

Seriously, there is little point asking questions of the form "why didn't they design Java the way that I would have done it?". They won't actually help you in doing your job ... unless your job is designing programming languages. And if it is, then you probably already understand that it is impossible to resolve conflicting PL design requirements in a way that satisfies everyone.

Upvotes: 0

user1803551
user1803551

Reputation: 13427

Can there be Java interfaces that aren't annotations?

Yes, regular interfaces:

public interface MyInterface {...}

Can @Interface be used to declare something other than an annotation as well?

No, @interface defines an annotation. And be careful with the letter case - it's smallcase @interface, not @Interface.

why not just call it @Annotation or something?

Because annotations are a type of interface, see the answer I gave to your other question,

An annotation type declaration specifies a new annotation type, a special kind of interface type.

(bold emphasis is mine) and from the tutorial:

Annotation types are a form of interface

Upvotes: 1

Related Questions