How convert a data from Hexa to Byte Array
Problem! Promote the conversion between hex data to byte array and reverse. Sample: Hex 30 = 0 Byte[48] = 0 Java final protected static char [] HEX_ARRAY = "0123456789ABCDEF" .toCharArray(); private static byte [] toByteArray(String hexString) throws HexStringException { int len = hexString.length(); byte [] data = new byte [len / 2]; try { for ( int i = 0; i < len; i += 2) { data[i / 2] = ( byte ) ((Character.digit(hexString.charAt(i), 16) << 4) + Character.digit(hexString.charAt(i + 1), 16)); } } catch (Exception e) { throw new HexStringException(e); } return data; } private static String fromByteArray( byte [] buffer ) { char[] hexChars = new char [buffer. length * 2]; for ( int j = 0; j < buffer. length ; j++) { int v = buffer[j] & 0xFF; hexChars[j * 2] = HE