### Question:
ByteUtils { public static String bytesToHex(byte[] bytes) { char[] hexChars = new char[bytes.length * 2]; for (int j = 0; j < bytes.length; j++) { int v = bytes[j] & 0xFF; hexChars[j * 2] = hexArray[v >>> 4]; hexChars[j * 2 + 1] = hexArray[v & 0x0F]; } return new String(hexChars); }  static String bytesToHex(byte[] bytes); static byte[] combineByteArrays(byte[] one, byte[] two); static byte[] fromHexString(String hexString);  }### Answer:
@Test public void testBytesToHex() { final String hex = ByteUtils.bytesToHex("coinfinity".getBytes()); assertEquals("636F696E66696E697479", hex); }