title: When does BufferedWriter create file?
body: <p>Using BufferedWriter.write() when is a file created?</p>
  
  <p>I know from the docs that when the buffer is filled it will flush to file, does this mean that:</p>
  
  <p>every-time the buffer is filled an incomplete file will appear on my file system?</p>
  
  <p>or that the file is only created when the BufferedWriter is closed?</p>
  
  <p>My concern is that I am writing files to a directory using a BufferedWriter and another process is polling the directory for new files and reading them. I do not want an incomplete file to be created and be read by the other process.</p>