title: java how calculate hash of file data without loading file in memory (without read all bytes)
body: <p>Having this problem, you need to somehow calculate the md5 hash of file content without reading into a byte array because:
  1) file can be larger than 2GB
  2) do not have enough memory to download a large file.</p>
  
  <p>what can be done?
  search in Google gave nothing.
  thanks and sorry for my bad english</p>