Question

I want to create a custom annotation (using Java) which would accept other annotations as parameter, something like:

public @interface ExclusiveOr {     Annotation[] value(); } 

But this causes compiler error ‘invalid type for annotation member’.

Object[] also doesn’t work.

Is there a way to do what I want?

Answer 1

I myself hereby propose a workaround for the given problem:

Well, what I wanted to make possible was something like that:

@Contract({     @ExclusiveOr({         @IsType(IAtomicType.class),         @Or({             @IsType(IListType.class),             @IsType(ISetType.class)         })     }) }) 

Proposed workaround:

Define a class with parameter-less constructor (which will be called by your own annotation processor later) in following way:

final class MyContract extends Contract{     // parameter-less ctor will be handeled by annotation processor     public MyContract(){         super(             new ExclusiveOr(                 new IsType(IAtomicType.class),                 new Or(                     new IsType(IListType.class),                     new IsType(ISetType.class)                 )             )         );     } } 

usage:

@Contract(MyContract.class) class MyClass{     // ... }