public DateTimeFormatterBuilder appendFixedSignedDecimal(
            DateTimeFieldType fieldType, int numDigits) {
        if (fieldType == null) {
            throw new IllegalArgumentException("Field type must not be null");
        }
        if (numDigits <= 0) {
            throw new IllegalArgumentException("Illegal number of digits: " + numDigits);
        }
        return append0(new FixedNumber(fieldType, numDigits, true));
    }
public DateTimeFormatterBuilder appendFixedSignedDecimal ( DateTimeFieldType fieldType , int numDigits ) { if ( fieldType == null ) { throw new IllegalArgumentException ( "Field type must not be null" ) ; } if ( numDigits <= 0 ) { throw new IllegalArgumentException ( "Illegal number of digits: " + numDigits ) ; } return append0 ( new FixedNumber ( fieldType , numDigits , true ) ) ; }
Instructs the printer to emit a field value as a fixed-width decimal
number (smaller numbers will be left-padded with zeros), and the parser
to expect an signed decimal number with the same fixed width.

@param fieldType  type of field to append
@param numDigits  the exact number of digits to parse or print, except if
printed value requires more digits
@return this DateTimeFormatterBuilder, for chaining
@throws IllegalArgumentException if field type is null or if <code>numDigits <= 0</code>
@since 1.5