code: public static byte[] convertFromHex(final char[] toConvert) {
          if (toConvert.length % 2 != 0) {
              throw new IllegalArgumentException("The supplied character array must contain an even number of hex chars.");
          }
  
          byte[] response = new byte[toConvert.length / 2];
  
          for (int i = 0; i < response.length; i++) {
              int posOne = i * 2;
              response[i] =   (byte)(toByte(toConvert, posOne) << 4 | toByte(toConvert, posOne+1));
          }
  
          return response;
      }
docs: Take the incoming character of hex encoded data and convert to the raw byte values.
  <p>
  The characters in the incoming array are processed in pairs with two chars of a pair
  being converted to a single byte.
  
  @param toConvert - the hex encoded String to convert.
  @return the raw byte array.