### Question:
Hexer { public static String hexify(byte[] data) { StringBuffer hex = new StringBuffer(); for (int i = 0; i < data.length; i++) { int highBits = ((int) data[i] & 0x000000F0) >> 4; int lowBits = ((int) data[i] & 0x0000000F); hex.append(hexChars[highBits]).append(hexChars[lowBits]); } return (hex.toString()); }  static String hexify(byte[] data); static String stringify(byte[] data); static byte[] parse(final String stringOfSpaceSeparatedHex); static byte[] parse(final String[] hexValues); static byte[] dehexify(String data);  }### Answer:
@Test public void hexify() { assertEquals("Representation of a byte array in hex", s, Hexer.hexify(b)); }