http://findbugs.sourceforge.net/: Annotation the FindBugs tool supports 
package javax.annotation.meta;

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


This qualifier is applied to an annotation to denote that the annotation
should be treated as a type qualifier.

/**
 * This qualifier is applied to an annotation to denote that the annotation
 * should be treated as a type qualifier.
 */

@Documented
@Target(ElementType.ANNOTATION_TYPE)
@Retention(RetentionPolicy.RUNTIME)
public @interface TypeQualifier {

    
Describes the kinds of values the qualifier can be applied to. If a
numeric class is provided (e.g., Number.class or Integer.class) then the
annotation can also be applied to the corresponding primitive numeric
types.

/**
     * Describes the kinds of values the qualifier can be applied to. If a
     * numeric class is provided (e.g., Number.class or Integer.class) then the
     * annotation can also be applied to the corresponding primitive numeric
     * types.
     */
    Class<?> applicableTo() default Object.class;

}