question: private void validateNames ( Label label , Parameter parameter ) throws Exception { String [ ] options = label . getNames ( ) ; String name = parameter . getName ( ) ; if ( ! contains ( options , name ) ) { String require = label . getName ( ) ; if ( name != require ) { if ( name == null || require == null ) { throw new ConstructorException ( "Annotation does not match %s for '%s' in %s" , label , name , parameter ) ; } if ( ! name . equals ( require ) ) { throw new ConstructorException ( "Annotation does not match %s for '%s' in %s" , label , name , parameter ) ; } } } }
target:  This is used to validate the names associated with the parameters. Validation is performed by checking that the parameter name is present in the list of names the label is known by. This is used to ensure that the if the label is a union the parameter is one of the names declared within the union.