public synchronized void flush() throws IOException {
  if (closed) {
    return;
  }
  flushBuffer();
  out.flush();
  lastActivityTime=System.currentTimeMillis();
}

public synchronized void flush ( ) throws IOException { if ( closed ) { return ; } flushBuffer ( ) ; out . flush ( ) ; lastActivityTime = System . currentTimeMillis ( ) ; }
flushes this buffered output stream . this forces any buffered output bytes to be written out to the underlying output stream .
