@Override
    protected void processRequestPayload(SignableRequest<?> request, byte[] signature,
            byte[] signingKey, AWS4SignerRequestParams signerRequestParams) {
        if (useChunkEncoding(request)) {
            AwsChunkedEncodingInputStream chunkEncodededStream = new AwsChunkedEncodingInputStream(
                    request.getContent(), signingKey,
                    signerRequestParams.getFormattedSigningDateTime(),
                    signerRequestParams.getScope(),
                    BinaryUtils.toHex(signature), this);
            request.setContent(chunkEncodededStream);
        }
    }
If necessary, creates a chunk-encoding wrapper on the request payload.
aws-java-sdk-s3/src/main/java/com/amazonaws/services/s3/internal/AWSS3V4Signer.java