code: public static boolean isDigit(int ch)
     {
        return (0x0030 <= ch && ch <= 0x0039) || (0x0660 <= ch && ch <= 0x0669) || (0x06F0 <= ch && ch <= 0x06F9)
           || (0x0966 <= ch && ch <= 0x096F) || (0x09E6 <= ch && ch <= 0x09EF) || (0x0A66 <= ch && ch <= 0x0A6F)
           || (0x0AE6 <= ch && ch <= 0x0AEF) || (0x0B66 <= ch && ch <= 0x0B6F) || (0x0BE7 <= ch && ch <= 0x0BEF)
           || (0x0C66 <= ch && ch <= 0x0C6F) || (0x0CE6 <= ch && ch <= 0x0CEF) || (0x0D66 <= ch && ch <= 0x0D6F)
           || (0x0E50 <= ch && ch <= 0x0E59) || (0x0ED0 <= ch && ch <= 0x0ED9) || (0x0F20 <= ch && ch <= 0x0F29);
     }
docs: Returns true if the specified character is a digit as defined by production [88] in the XML 1.0
  specification.
  
  @param ch
  The character to check.