我编写了一个简单的servlet，如下所示：

public class MyServlet extends HttpServlet {
    public void doGet(HttpServletRequest request, HttpServletResponse response)
           throws ServletException, IOException {
        PrintWriter out = response.getWriter();
        // [do stuff with the PrintWriter]
        out.close();
    }
}

是否需要关闭PrintWriter流？如果我不关闭流，那会进一步影响吗？