How to use

MD5DigestCalculatingInputStream

in

com.amazonaws.services.s3.internal

@Override
public void mark(int readlimit) {
  if (markSupported()) {
    super.mark(readlimit);
    digestLastMarked = cloneFrom(digest);
  }
}

private void resetDigest() {
  try {
    digest = MessageDigest.getInstance("MD5");
  } catch (NoSuchAlgorithmException e) {
    throw new IllegalStateException("No message digest support for MD5 was found.", e);
  }
  digestCanBeCloned = canBeCloned(digest);
}

/**
 * Resets the wrapped input stream and the in progress message digest.
 */
@Override
public void reset() throws IOException {
  if (markSupported()) {
    super.reset();
    if (digestLastMarked == null) {
      resetDigest();
    } else {
      digest = cloneFrom(digestLastMarked);
    }
  } else {
    throw new IOException("mark/reset not supported");
  }
}

  input = md5DigestStream = new MD5DigestCalculatingInputStream(input);
contentMd5 = Base64.encodeAsString(md5DigestStream.getMd5Digest());

MD5DigestCalculatingInputStream is = new MD5DigestCalculatingInputStream(
    new ByteArrayInputStream(data));
baExpected = IOUtils.toByteArray(is);
byte[] md5 = is.getMd5Digest();
assertTrue(Arrays.equals(md5Expected, md5));
MD5DigestCalculatingInputStream is = new MD5DigestCalculatingInputStream(
    new ByteArrayInputStream(data));
is.mark(-1);
baExpected = IOUtils.toByteArray(is);
byte[] md5 = is.getMd5Digest();
assertTrue(Arrays.equals(md5Expected, md5));
is.reset();
byte[] ba = IOUtils.toByteArray(is);
byte[] md5_2 = is.getMd5Digest();
assertTrue(Arrays.equals(md5Expected, md5_2));
assertTrue(Arrays.equals(baExpected, ba));
MD5DigestCalculatingInputStream is = new MD5DigestCalculatingInputStream(
    new ByteArrayInputStream(data));
is.mark(-1);
is.read(new byte[10]);
is.reset();
byte[] ba = IOUtils.toByteArray(is);
if (DEBUG)
  System.out.println("ba.length: " + ba.length);
assertTrue(Arrays.equals(baExpected, ba));
byte[] md5 = is.getMd5Digest();

/**
 * Resets the wrapped input stream and the in progress message digest.
 */
@Override
public void reset() throws IOException {
  if (markSupported()) {
    super.reset();
    digest = (digestLastMarked == null)
        // This is necessary so that should there be a reset without a
        // preceding mark, the MD5 would still be computed correctly.
        ? newMD5()
        : cloneFrom(digestLastMarked);
  } else {
    throw new IOException("mark/reset not supported");
  }
}

byte[] clientSideHash = md5DigestStream.getMd5Digest();
byte[] serverSideHash = BinaryUtils.fromHex(etag);

isCurr = md5DigestStream = new MD5DigestCalculatingInputStream(isCurr);

public MD5DigestCalculatingInputStream(InputStream in) {
  super(in);
  resetDigest();
  if (in.markSupported() && !digestCanBeCloned) {
    log.debug("Mark-and-reset disabled on MD5 calculation because the digest implementation does not support cloning. "
         + "This will limit the SDK's ability to retry requests that failed. Consider pre-calculating the MD5 "
         + "checksum for the request or switching to a security provider that supports message digest cloning.");
  }
}

/**
 * Constructor.
 * @param in input stream
 */
public MD5DigestCalculatingInputStream(InputStream in) {
  super(in);
  digest = newMD5();
}

inputStream = md5DigestStream = new MD5DigestCalculatingInputStream(inputStream);
  final byte[] clientSideHash = md5DigestStream.getMd5Digest();
  final byte[] serverSideHash = BinaryUtils.fromHex(metadata.getETag());

/**
 * Resets the wrapped input stream and the in progress message digest.
 */
@Override
public void reset() throws IOException {
  if (markSupported()) {
    super.reset();
    digest = (digestLastMarked == null)
        // This is necessary so that should there be a reset without a
        // preceding mark, the MD5 would still be computed correctly.
        ? newMD5()
        : cloneFrom(digestLastMarked);
  } else {
    throw new IOException("mark/reset not supported");
  }
}

byte[] clientSideHash = md5DigestStream.getMd5Digest();
byte[] serverSideHash = BinaryUtils.fromHex(etag);

isCurr = md5DigestStream = new MD5DigestCalculatingInputStream(isCurr);

public MD5DigestCalculatingInputStream(InputStream in) {
  super(in);
  resetDigest();
  if (in.markSupported() && !digestCanBeCloned) {
    log.debug("Mark-and-reset disabled on MD5 calculation because the digest implementation does not support cloning. "
         + "This will limit the SDK's ability to retry requests that failed. Consider pre-calculating the MD5 "
         + "checksum for the request or switching to a security provider that supports message digest cloning.");
  }
}

/**
 * Constructor.
 * @param in input stream
 */
public MD5DigestCalculatingInputStream(InputStream in) {
  super(in);
  digest = newMD5();
}

input = md5DigestStream = new MD5DigestCalculatingInputStream(input);
contentMd5 = BinaryUtils.toBase64(md5DigestStream.getMd5Digest());

@Override
public void mark(int readlimit) {
  if (markSupported()) {
    super.mark(readlimit);
    digestLastMarked = cloneFrom(digest);
  }
}

/**
 * Resets the wrapped input stream and the in progress message digest.
 */
@Override
public void reset() throws IOException {
  if (markSupported()) {
    super.reset();
    if (digestLastMarked == null) {
      resetDigest();
    } else {
      digest = cloneFrom(digestLastMarked);
    }
  } else {
    throw new IOException("mark/reset not supported");
  }
}

private void resetDigest() {
  try {
    digest = MessageDigest.getInstance("MD5");
  } catch (NoSuchAlgorithmException e) {
    throw new IllegalStateException("No message digest support for MD5 was found.", e);
  }
  digestCanBeCloned = canBeCloned(digest);
}