download.java~1~

功能描述： 1：管理员和普通用户采用同一页面登陆。 2：普通用户可以查看和修改自己的登陆密码。 3：普通用户可以给系统内的每一为人员发送信息

package inc;

import java.io.*;

import javax.servlet.*;
import javax.servlet.http.*;


public class Download extends HttpServlet {

 public void init() throws ServletException {
 }

 public void destroy() {
  super.destroy();
 }

 protected void doGet(HttpServletRequest request,
   HttpServletResponse response) throws ServletException, IOException {
          request.setCharacterEncoding("utf-8");
        response.setCharacterEncoding("utf-8");
     String root = getServletContext().getRealPath("/");
     String path="uploadFiles\\";
     String name = request.getParameter("name");
      //PrintWriter out=response.getWriter();
      
     HttpSession session = request.getSession();
     String username = (String) session.getAttribute("username");
     String id = (String) session.getAttribute("id");

     response.setContentType("application/x-msdownload");
     response.addHeader("Content-Disposition","attachment; filename=\"" + name + "\"");
     response.setContentLength((int)name.length()); 
         
      if (username == null) {
      response.sendRedirect("index.html");
      return;
         }
     
     try
     {

        


         byte[] b = new byte[1024];
         int    i = 0;
         String downpath=root + path + name;
         FileInputStream fis = new FileInputStream(downpath);
         ServletOutputStream  os  = response.getOutputStream();
         while ( (i = fis.read(b)) != -1 ) 
         {
             os.write(b, 0, i);
         }
         
         fis.close();
         os.flush();
         os.close();
     }
     catch ( Exception e )
     {
      e.printStackTrace();
     }
  }
 
   public void doPost(HttpServletRequest req, HttpServletResponse resp) throws
      ServletException, IOException {
    doGet(req, resp);
  }
 }