code: public static void flushQuietly(Flushable flushable) {
      try {
        flush(flushable, true);
      } catch (IOException e) {
        logger.log(Level.SEVERE, "IOException should not have been thrown.", e);
      }
    }
docs: Equivalent to calling {@code flush(flushable, true)}, but with no {@code IOException} in the
  signature.
  
  @param flushable the {@code Flushable} object to be flushed.