Java: upload file without buffering

I’m using MultipartEntity to upload files. But I find it writes the entire file to a buffer and then does the upload. It takes more time and more memory. Here is a part of my code:

MultipartEntity mulpartEntity = new 
MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE);
FileBody fileBody = new FileBody(file, TYPE_BINARY);
FormBodyPart formBodyPart = new FormBodyPart(fileName, fileBody);
multipartEntity.addPart(formBodyPart);
request.setEntity(multipartEntity);

Does anyone have the idea to upload files without buffering?