Untitled

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
    response.setContentType("text/html");
    PrintWriter out = response.getWriter();
    String title = "Delete Tutorial Subject";
    HttpSession s = request.getSession(true);
    out.print(ServletUtilities.headWithTitle(title) + "<H3 ALIGN=CENTER>" + title + "</H3>");
    if(request.getParameter("btnSubmit")!=null)
    {
        String topictodelete = request.getParameter("subjectToDelete");
        InputStream    input = null;
        BufferedReader filereader = null;
        OutputStream output = null;
        PrintWriter o = null;
        File folder = new File("D:\FileServer\"+topictodelete);
        deleteDirectory(folder);
        File mainfile = new File("D:\FileServer\main.txt");
        File tempfile = new File("D:\FileServer\temp.txt");
        try {
            tempfile.createNewFile();
            input = new FileInputStream("D:\FileServer\main.txt");
            filereader = new BufferedReader(new InputStreamReader(input));
            String lineread = "";
            output = new FileOutputStream("D:\FileServer\temp.txt");
            o = new PrintWriter(new BufferedWriter(new OutputStreamWriter(output)), true);
            while  (((lineread = filereader.readLine()) != null))
            {
                if(!topictodelete.equalsIgnoreCase(lineread))
                {
                    o.println(lineread);
                }
            }
            } catch (IOException e) {
            e.printStackTrace();
        }
        finally
        {
            filereader.close();
            o.close();
            input.close();
            output.close();
        }
        out.println ("<html><body><script>alert('This may take some time. " +
        "Please donot reload or navigate from  this page');</script></body></html>");
        while(mainfile.exists())
        {
            System.out.print("shit");
            mainfile.delete();
        }
        tempfile.renameTo(mainfile);
        out.println ("<html><body><script>alert('Tutorial Deleted');</script></body></html>");
    }
    if(((String)s.getAttribute("User")).equals("Admin"))
    {
        InputStream    inputs = new FileInputStream("D:\FileServer\main.txt");
        BufferedReader inp = new BufferedReader(new InputStreamReader(inputs));
        String l;
        out.println("<form ACTION="/mmm/DeleteSubject" method="post">");
        out.print("<select id="subjectToDelete" name="subjectToDelete">");
        while (((l = inp.readLine()) != null))
        {
            out.print("<option value=""+l+"">"+l+"</option>");
        }
        out.print("</select>");
        out.print("<input type="submit" id="btnSubmit" name="btnSubmit" value="Delete"/>");
        out.print("</form>");
    }
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException
{
    doGet(request, response);
}