[jboss-user] [JBoss Seam] - Re: Can you merge multiple annotations in one?

[CptnKirk]

Actually I'm pretty sure Java does have limited meta-annotation support.  Look at how Seam implements its DataBinding mechanism.


  | @Target(ANNOTATION_TYPE)
  | @Retention(RUNTIME)
  | @Documented
  | public @interface DataBinderClass
  | {
  |    Class<? extends DataBinder> value();
  | }

Then in whatever your databinder annotation is

  | @Target({FIELD, METHOD})
  | @Retention(RUNTIME)
  | @Documented
  | @DataBinderClass(SelectItemsBinder.class)
  | public @interface SelectItems
  | {...

Code that looks for @DataBinderClass annotated elements will also find elements annotated with @SelectItems.  This is all pretty static, so you won't have the nice macro effect that you're looking for, but could have your own @SeamSLSB annotation that encapsulates some boilerplate code (including imports).  I haven't tried this with any annotation other than @DataBinderClass, and it has a @Target(ANNOTATION_TYPE).  It's possible that other Seam annotations may also work those with @Target(TYPE), it's possible things may fail.  Good luck.

I hope this is useful.

-Jim

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