### Question:
ByteUtils { public static byte[] fromHexString(String hexString) { hexString = hexString.replaceAll("\\s+", ""); int len = hexString.length(); if (!isNumeric(hexString) || len % 2 != 0) { return new byte[]{}; } byte[] data = new byte[len / 2]; 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)); } return data; }  static String bytesToHex(byte[] bytes); static byte[] combineByteArrays(byte[] one, byte[] two); static byte[] fromHexString(String hexString);  }### Answer:
@Test public void testFromHexString() { final byte[] bytes = ByteUtils.fromHexString("636F696E66696E697479"); assertEquals("coinfinity", new String(bytes)); }