code: public DateTimeFormatterBuilder appendShortText(DateTimeFieldType fieldType) {
          if (fieldType == null) {
              throw new IllegalArgumentException("Field type must not be null");
          }
          return append0(new TextField(fieldType, true));
      }
docs: Instructs the printer to emit a field value as short text, and the
  parser to expect text.
  
  @param fieldType  type of field to append
  @return this DateTimeFormatterBuilder, for chaining
  @throws IllegalArgumentException if field type is null