@Override public StringBuffer format(Object        obj,
                                             StringBuffer  toAppendTo,
                                             FieldPosition pos) {
            if (obj != null) {
                toAppendTo.append(obj);
            }

            return toAppendTo;
        }
@Override public StringBuffer format(Object        obj,
                                             StringBuffer  toAppendTo,
                                             FieldPosition pos)