question: public static String fieldName ( Class < ? > aClass , String regex ) { if ( isNestedMapping ( regex ) ) return regex ; String result = null ; for ( Class < ? > clazz : getAllsuperClasses ( aClass ) ) if ( ! isNull ( result = getFieldName ( clazz , regex ) ) ) return result ; return result ; }
target:  This method returns the name of the field whose name matches with regex.