Re: Multiple Annotations of the same type?

From:

Joshua Cranmer <Pidgeot18@verizon.net>

Newsgroups:

comp.lang.java.programmer

Date:

Fri, 10 Aug 2007 22:19:52 GMT

Message-ID:

<cw5vi.2172$2C4.1371@trndny07>

zakmck73@yahoo.it wrote:

Hi all,

I have a question about Java annotations. I find weird I cannot
annotate something multiple times using the same annotation type. For
instance I cannot do this:

@TODO ( type = "urgent", "Fix the bugs!" )
@TODO ( type = "low priority", "Check the comments" )
public class Foo
{
...
}

AFAIK, there is no technical reason why that cannot be true.

I wish that on the reflection side I had something like
getAnnotationsByType ( Class clazz ).

You have getAnnotation(Class<T> annotationType) [see below]

Any chance things will be improved in future?

There's a chance; I don't think it's high on anyone's list of things to
do, though.

> Does anyone know a workaround?

When I ran into this problem, I created a new supra-annotation:

public @interface Option {
  [...]
}

public @interface Options {
   Option[] annotations();
}

And used at as such:

@Options({
    @Option( [...] ),
    @Option( [...] )
})
public class Foobar {
     [ ... ]
}

--
Beware of bugs in the above code; I have only proved it correct, not
tried it. -- Donald E. Knuth