Well... You don't have to create one java file for each class. You can put all of them on the same file, like:

public final class MyAppRoles {
   private MyAppRoles() {}
   public static final class Admin extends Role {
       private Admin() {}
   }

   public static final class User extends Role {
       private User() {}
   }
}

Note that this is really type-safe, and these classes will never be instantiated. But, I'm not defending that we should change that. I'm just showing a possibility. :-)

I really did't understand why Sun decided to reject Enums as Objects in this context of annotations.

cheers,
Bruno

James Carman wrote:
I don't know about this.  It would work (and break existing code, unless you
use something other than value for the annotation).  I don't know if I would
want to have to create a new class for each role in my project.  Yes, it
would be a small price to pay, but it just feels wrong.

On Thu, Dec 4, 2008 at 10:33 PM, Bruno Borges <[EMAIL PROTECTED]>wrote:

I've found a way to implement a type-safe check for this. Here it goes:

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Inherited;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

@AuthorizeInstantiation(value = { User.class, Admin.class })
public class EnumAnnotation {

}

@Retention(RetentionPolicy.RUNTIME)
@Target( { ElementType.PACKAGE, ElementType.TYPE })
@Documented
@Inherited
@interface AuthorizeInstantiation {

  Class<? extends Role>[] value() default {};

}

class Role {
}

class User extends Role {
}

class Admin extends Role {
}

So, the only thing that must change is the annotation
@AuthorizeInstantiation, to accept classes that extends roles.

Thoughts anyone?

cheers,
Bruno



Bruno Borges wrote:

You simply can't do that because the nature of Annotations.

Even if AuthorizeInstantiation's values were of type Object[] you wouldn't
be able to do that with Enums.

You will have to use Strings.

Although there's some hack you can make using Java 6 to accomplish what
you want. If you are interested, take a look at this link:

http://www.iam.unibe.ch/~akuhn/blog/2008/roman-numerals-in-your-java/<http://www.iam.unibe.ch/%7Eakuhn/blog/2008/roman-numerals-in-your-java/>

Good luck!!

Cheers,
Bruno

miro wrote:

I am using this  @AuthorizeInstantiation   (wicket authetication
annotation)
in my pages , the code for this annotation

@Retention(RetentionPolicy.RUNTIME)
@Target( { ElementType.PACKAGE, ElementType.TYPE })
@Documented
@Inherited
public @interface AuthorizeInstantiation {

   /**
    * Gets the roles that are allowed to take the action.
    *      * @return the roles that are allowed. Returns a zero length
array by
default
    */
   String[] value() default {};
}


I created my enum with representing authorities

public enum  Authorities {
       LIASION_OFFICER,
   GRANTS_OFFICER,
   PROGRAM_ANALYST,
   ADMIN;

}

I am trying to use  AuthorizeInstantiation   in my page  here an example
@AuthorizeInstantiation(value={Authorities.LIASION_OFFICER.name()})
public class HomePage extends BasePage {


this line does not compile, I get the error
The value of annotation attribute AuthorizeInstantiation .value must be a
constant expression  .please help me resolve this .


---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]




---------------------------------------------------------------------
To unsubscribe, e-mail: [EMAIL PROTECTED]
For additional commands, e-mail: [EMAIL PROTECTED]

Reply via email to