PUT /testbbucket/caddy HTTP/1.1 1 1 map[X-Amz-Content-Sha256:[STREAMING-AWS4-HMAC-SHA256-PAYLOAD] User-Agent:[aws-sdk-java/1.10.41 Mac_OS_X/10.11.1 Java_HotSpot(TM)_64-Bit_Server_VM/25.25-b02/1.8.0_25] Content-Type:[application/octet-stream] Content-Length:[12241473] Connection:[Keep-Alive] X-Amz-Date:[20151218T164446Z] X-Amz-Decoded-Content-Length:[12232928] Content-Md5:[4uUkMUjnvb+ymFcDSeexUA==] Authorization:[AWS4-HMAC-SHA256 Credential=WLGDGYAQYIGI833EV05A/20151218/us-east-1/s3/aws4_request, SignedHeaders=content-length;content-md5;content-type;host;user-agent;x-amz-content-sha256;x-amz-date;x-amz-decoded-content-length, Signature=6575c62db878f4151357f54b4e7a5c19555afb1a9efc0573dce615850caaf646]] 0xc82017a140 12241473 [] false localhost:9000 map[] map[] <nil> map[] 127.0.0.1:50544 /testbbucket/caddy <nil> <nil>

Following code makes it default - i couldn't find a way to override this, is there any?

/**
     * Determine whether to use aws-chunked for signing
     */
    private static boolean useChunkEncoding(SignableRequest<?> request) {
        // Whether to use chunked encoding for signing the request
        boolean chunkedEncodingEnabled = false;
        if (request.getOriginalRequestObject() instanceof PutObjectRequest
                || request.getOriginalRequestObject() instanceof UploadPartRequest) {
            chunkedEncodingEnabled = true;
        }
        return chunkedEncodingEnabled;
    }

The behavior is entirely different than how aws-sdk-go behaves which does calculate the sha256 during multipart and regular put operation.