### Question:
ByteUtils { public static byte[] combineByteArrays(byte[] one, byte[] two) { byte[] combined = new byte[one.length + two.length]; System.arraycopy(one, 0, combined, 0, one.length); System.arraycopy(two, 0, combined, one.length, two.length); return combined; }  static String bytesToHex(byte[] bytes); static byte[] combineByteArrays(byte[] one, byte[] two); static byte[] fromHexString(String hexString);  }### Answer:
@Test public void testCombineByteArrays() { final byte[] combineByteArrays = ByteUtils.combineByteArrays("coinfinity".getBytes(), "infineon".getBytes()); assertEquals("coinfinityinfineon", new String(combineByteArrays)); }