This annotation is applied to a annotation, and marks the annotation as being a qualifier nickname. Applying a nickname annotation X to a element Y should be interpreted as having the same meaning as applying all of annotations of X (other than QualifierNickname) to Y.

Thus, you might define a qualifier SocialSecurityNumber as follows:

@Documented
@TypeQualifierNickname @Pattern("[0-9]{3}-[0-9]{2}-[0-9]{4}") 
@Retention(RetentionPolicy.RUNTIME)
public @interface SocialSecurityNumber {
}