}

  private static void assertChecksum(ImmutableSupplier<Checksum> supplier, String input) {
    byte[] bytes = HashTestUtils.ascii(input);

    Checksum checksum = supplier.get();
    checksum.update(bytes, 0, bytes.length);
    long value = checksum.getValue();

    String toString = "name";
    HashFunction func = new ChecksumHashFunction(supplier, 32, toString);

    }

    @Override
    public byte[] getExpected(byte[] bytes) {
      if (initialBytes == null) {
        return checkNotNull(bytes);
      } else {
        byte[] result = new byte[initialBytes.length + bytes.length];
        System.arraycopy(initialBytes, 0, result, 0, initialBytes.length);
        System.arraycopy(bytes, 0, result, initialBytes.length, bytes.length);
        return result;
      }
    }

      out.write(b);
    }

    @Override
    protected void update(byte[] b, int off, int len) {
      out.write(b, off, len);
    }

    byte[] bytes() {
      return out.toByteArray();
    }

    void assertBytes(byte[] expected) {
      assertArrayEquals(expected, bytes());
    }

    @Override
    public HashCode hash() {
      return HashCode.fromBytesNoCopy(bytes());

                SecureKeyManager.secureWipe(keyCopy);
            }
        }
    }

    private static byte[] longToBytes(final long value) {
        final byte[] bytes = new byte[8];
        for (int i = 0; i < 8; i++) {
            bytes[i] = (byte) (value >>> 8 * (7 - i));
        }
        return bytes;
    }

    /**
     * Check if key rotation is needed based on configurable usage limits
     *

                bytes[byteIndex++] = (byte) (0xC0 | (c >> 6));
                bytes[byteIndex++] = (byte) (0x80 | (c & 0x3F));
            } else {
                bytes[byteIndex++] = (byte) (0xE0 | (c >> 12));
                bytes[byteIndex++] = (byte) (0x80 | ((c >> 6) & 0x3F));
                bytes[byteIndex++] = (byte) (0x80 | (c & 0x3F));
            }
        }

        return Arrays.copyOf(bytes, byteIndex);
    }

    assertFalse(sink.wasStreamClosed());

    out.write(new byte[] {1, 2, 3, 4});
    out.close();

    assertTrue(sink.wasStreamClosed());
    assertArrayEquals(new byte[] {1, 2, 3, 4}, sink.getBytes());
  }

  public void testWrite_bytes() throws IOException {
    assertArrayEquals(new byte[0], sink.getBytes());
    sink.write(bytes);

    assertTrue(sink.wasStreamOpened() && sink.wasStreamClosed());

    assertFalse(sink.wasStreamClosed());

    out.write(new byte[] {1, 2, 3, 4});
    out.close();

    assertTrue(sink.wasStreamClosed());
    assertArrayEquals(new byte[] {1, 2, 3, 4}, sink.getBytes());
  }

  public void testWrite_bytes() throws IOException {
    assertArrayEquals(new byte[0], sink.getBytes());
    sink.write(bytes);

    assertTrue(sink.wasStreamOpened() && sink.wasStreamClosed());

        String name = "TEST            ";
        System.arraycopy(name.getBytes("US-ASCII"), 0, src, srcIndex + 13, 16);
        src[srcIndex + 28] = 0x00; // hex code
        src[srcIndex + 29] = 0x04; // flags
        // MAC address (6 bytes)
        byte[] mac = new byte[6];
        System.arraycopy(mac, 0, src, srcIndex + 31, 6);
        // Stats (6 bytes)
        byte[] stats = new byte[6];

  TestByteSource(byte[] bytes, TestOption... options) {
    this.bytes = checkNotNull(bytes);
    this.options = ImmutableSet.copyOf(options);
  }

  @Override
  public boolean wasStreamOpened() {
    return inputStreamOpened;
  }

  @Override
  public boolean wasStreamClosed() {
    return inputStreamClosed;
  }

  @Override
  public InputStream openStream() throws IOException {

            @Override
            public long bytes() {
                return KILOBYTE.bytes() * KILOBYTE.bytes();
            }

            @Override
            public String symbol() {
                return "MB";
            }
        },
        GIGABYTE {
            @Override
            public long bytes() {
                return MEGABYTE.bytes() * KILOBYTE.bytes();
            }

            @Override