Streaming operation differences between 1.x and 2.x of the AWS SDK for Java

Streaming operations, such as Amazon S3 getObject and putObject methods, support non-blocking I/O in version 2.x of the SDK. As a result, the request and response model objects no longer take an InputStream as a parameter. Instead, for synchronous requests the request object accepts RequestBody, which is a stream of bytes. The asynchronous equivalent accepts an AsyncRequestBody.

s3client.putObject(BUCKET, KEY, new File(file_path));

s3client.putObject(PutObjectRequest.builder()
                                 .bucket(BUCKET)
                                 .key(KEY)
                                 .build(),
                 RequestBody.of(Paths.get("myfile.in")));

A streaming response object accepts a ResponseTransformer for synchronous clients and a AsyncResponseTransformer for asynchronous clients in V2.

S3Object o = s3.getObject(bucket, key);
S3ObjectInputStream s3is = o.getObjectContent();
FileOutputStream fos = new FileOutputStream(new File(key));   

s3client.getObject(GetObjectRequest.builder().bucket(bucket).key(key).build(),
		ResponseTransformer.toFile(Paths.get("key")));

In the SDK for Java 2.x, streaming response operations have an AsBytes method to load the response into memory and simplify common type conversions in-memory.