code: public final static DateFormat getDateTimeInstance(int dateStyle,
                                                         int timeStyle)
      {
          return get(timeStyle, dateStyle, 3, Locale.getDefault(Locale.Category.FORMAT));
      }
docs: Gets the date/time formatter with the given date and time
  formatting styles for the default locale.
  @param dateStyle the given date formatting style. For example,
  SHORT for "M/d/yy" in the US locale.
  @param timeStyle the given time formatting style. For example,
  SHORT for "h:mm a" in the US locale.
  @return a date/time formatter.