docs: public boolean isNull()
      {   // Return true if all non null fields have data in them
          int fieldCount = this.getFieldCount();  // BaseField Count
          for (int fieldSeq = DBConstants.MAIN_FIELD; fieldSeq < fieldCount+DBConstants.MAIN_FIELD; fieldSeq++)
          {
              BaseField field = this.getField(fieldSeq);
              if ((!field.isNullable()) && (field.isNull()))
                  return true;            // This field can't be null!!!
          }
          return false;   // All fields okay
      }