### Question:
Utils { public static void validateArrayAllegedSize(byte[] data, int offset, int allegedSize) { if (data.length < Math.addExact(allegedSize, offset)) { throw new IllegalArgumentException("The specified size exceeds the size of the payload"); } }  static BigInteger unifiedNumericToBigInteger(String number); static String longToDateTime(long timestamp); static String getValueShortString(BigInteger number); static byte[] addressStringToBytes(String hex); static boolean isValidAddress(byte[] addr); static String getAddressShortString(byte[] addr); static SecureRandom getRandom(); static String getHashListShort(List<byte[]> blockHashes); static String getNodeIdShort(String nodeId); static long toUnixTime(long javaTime); static long fromUnixTime(long unixTime); static T[] mergeArrays(T[] ... arr); static String align(String s, char fillChar, int targetLen, boolean alignRight); static String repeat(String s, int n); static boolean contains(List<byte[]> list, byte[] valueToFind); static void validateArrayAllegedSize(byte[] data, int offset, int allegedSize); static byte[] safeCopyOfRange(byte[] data, int from, int size); static boolean isDecimalString(String s); static boolean isHexadecimalString(String s); static long decimalStringToLong(String s); static long hexadecimalStringToLong(String s); static final double JAVA_VERSION; }### Answer:
@Test public void TestValidateArrayWithOffset() { byte[] data = new byte[10]; Utils.validateArrayAllegedSize(data, 1, 0); Utils.validateArrayAllegedSize(data, 8, 1); Utils.validateArrayAllegedSize(data, 0, 10); Utils.validateArrayAllegedSize(data, 8, 2); Utils.validateArrayAllegedSize(data, 11, -1); Utils.validateArrayAllegedSize(data, -2, 12); try { Utils.validateArrayAllegedSize(data, 0, 11); fail("should have failed"); } catch (IllegalArgumentException e) { } try { Utils.validateArrayAllegedSize(data, 2, 9); fail("should have failed"); } catch (IllegalArgumentException e) { } try { Utils.validateArrayAllegedSize(new byte[0], 1, 0); fail("should have failed"); } catch (IllegalArgumentException e) { } byte[] noData = null; try { Utils.validateArrayAllegedSize(noData, 1, 1); fail("should have failed"); } catch (NullPointerException e) { } }