title: Deferring BufferedWriter.write to another thread
body: <p>I have an event processing scheme which should also eventually write to file; I cannot afford to delay the event when the file is being flushed, i.e. waiting to the end of BufferedWriter.write(String).</p>
  
  <p>I'm looking for the easiest way to achieve that (is there's a library doing that? I reckon that I'm not the only one who had this problem)</p>