### Question:
Utils { public static byte[] reverseBytes(byte[] bytes) { byte[] buf = new byte[bytes.length]; for (int i = 0; i < bytes.length; i++) buf[i] = bytes[bytes.length - 1 - i]; return buf; }  static byte[] bigIntegerToBytes(BigInteger b, int numBytes); static void uint16ToByteArrayLE(int val, byte[] out, int offset); static void uint32ToByteArrayLE(long val, byte[] out, int offset); static void uint32ToByteArrayBE(long val, byte[] out, int offset); static void int64ToByteArrayLE(long val, byte[] out, int offset); static void uint16ToByteStreamLE(int val, OutputStream stream); static void uint16ToByteStreamBE(int val, OutputStream stream); static void uint32ToByteStreamLE(long val, OutputStream stream); static void uint32ToByteStreamBE(long val, OutputStream stream); static void int64ToByteStreamLE(long val, OutputStream stream); static void uint64ToByteStreamLE(BigInteger val, OutputStream stream); static int readUint16(byte[] bytes, int offset); static long readUint32(byte[] bytes, int offset); static long readInt64(byte[] bytes, int offset); static long readUint32BE(byte[] bytes, int offset); static int readUint16BE(byte[] bytes, int offset); static int readUint16FromStream(InputStream is); static long readUint32FromStream(InputStream is); static byte[] reverseBytes(byte[] bytes); static byte[] sha256hash160(byte[] input); static BigInteger decodeMPI(byte[] mpi, boolean hasLength); static byte[] encodeMPI(BigInteger value, boolean includeLength); static BigInteger decodeCompactBits(long compact); static long encodeCompactBits(BigInteger value); static Date rollMockClock(int seconds); static Date rollMockClockMillis(long millis); static void setMockClock(); static void setMockClock(long mockClockSeconds); static Date now(); static long currentTimeMillis(); static long currentTimeSeconds(); static String dateTimeFormat(Date dateTime); static String dateTimeFormat(long dateTime); static boolean checkBitLE(byte[] data, int index); static void setBitLE(byte[] data, int index); static void sleep(long millis); static void setMockSleep(boolean isEnable); static void passMockSleep(); static void finishMockSleep(); static int maxOfMostFreq(int... items); static int maxOfMostFreq(List<Integer> items); static boolean isAndroidRuntime(); static boolean isLinux(); static boolean isWindows(); static boolean isMac(); static final Joiner SPACE_JOINER; static final Splitter WHITESPACE_SPLITTER; static final BaseEncoding HEX; static final int MAX_INITIAL_ARRAY_LENGTH; static volatile Date mockTime; }### Answer:
@Test public void testReverseBytes() { assertArrayEquals(new byte[]{1, 2, 3, 4, 5}, Utils.reverseBytes(new byte[]{5, 4, 3, 2, 1})); }