servlet怎么转向啊?

Question

首先，你要在被调用的servlet里面加入对自己的标记，类似这样(比如你要调用的servle名叫yourServlet)：getServletContext().setAttribute("yourservlet",this);
然后你可以在需要调用的地方，这样：
yourServlet yourserv = (yourServlet)getServletContext().getAttribute("yourservlet");

Answer 1

我主要是想问目录访问的问题,我用ie访问总得到404错误,就是找不到对应的urlresponse.sendredirect("????");
这个???里这么写?

Answer 2

就是你要指向的URI， 比如/index.jsp还可以用request.getRequestDispatcher("/index.jsp").forward(request, response);

Answer 3

/index.jsp 与index.jsp应该有区别吧,和目录也有区别吧???

Answer 4

package com.tt.genwesite.servlet;import com.tt.genwesite.util.*;
import com.tt.genwesite.bean.SysConfValidator;
import org.apache.log4j.*;//开源的日志管理包
import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;
import java.lang.Integer;
import java.sql.*;/**
 * Title:
 * Description:
 * Copyright:    Copyright (c) 2002
 * Company:
 * @author
 * @version 1.0
 */public class SessionServlet extends HttpServlet {
  private static final String CONTENT_TYPE = "text/html; charset=GBK";
  /**Initialize global variables*/
  public void init() throws ServletException {
  }
  /**Process the HTTP Get request*/
  public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    response.setContentType(CONTENT_TYPE);
       String url="";
        String login_name="";
        String user_pass="";
    ///////
  try {
    HttpSession session = request.getSession(false);    login_name=(String)session.getAttribute("login_name");
    user_pass=(String)session.getAttribute("user_pass");
      }catch(Exception e){
   System.out.println("参数错误：获取SESSION失败");
   response.sendRedirect("/course/login.jsp");
   }
    if (login_name==null||user_pass==null||user_pass.equals("")||login_name.equals(""))
{
response.sendRedirect("/course/login.jsp");
}    ///////
   //String sort = "";   //sort=request.getParameter("sort");
  try {
   url=request.getParameter("url");
   }
   catch(Exception e){
   System.out.println("参数错误：未得到期望的参数");
   response.sendRedirect("/course/login.jsp");
   }
   //得到当前月份如2002-03
         /*
        Calendar cal;
String tTheDate="";
        String month="";
        int year=0;
        int monthT=0;                  //tTheDate=request.getParameter("thedate");
                  //if(tTheDate.equals(null) || tTheDate.equals(""))
                  //{
                   cal=Calendar.getInstance();
         year=cal.get(Calendar.YEAR);
         monthT=cal.get(Calendar.MONTH);
         if(monthT<10)
         {
         month="0"+monthT;
         }         tTheDate=year+"-"+month;
         //}              Cookie[] myCookie=new Cookie[3]; for(int i=0;i<3;i++){
                     if(i==0)
                        myCookie[i]=new Cookie("sort",sort);
                     else if(i==1)
myCookie[i]=new Cookie("Cookie"+i,"Value"+i);
                        ///
myCookie[i].setMaxAge(200);
response.addCookie(myCookie[i]); }
   PrintWriter out = response.getWriter();
   out.println(sort);
   */         if(url== null || url.equals(""))
         {
                response.sendRedirect("/course/login.jsp");
                return;
         }
                else
                {
                //url=url+"?thedate="+tTheDate;
                   //设置页面session
                  //HttpSession sessionURL=request.getSession(true);
                  //sessionURL.setAttribute("url","on");
                  //sessionURL.setMaxInactiveInterval(300);
               ////
               Cookie[] myCookie=new Cookie[1]; for(int i=0;i<1;i++){
                     if(i==0)
                        myCookie[i]=new Cookie("url","on");
              myCookie[i].setMaxAge(3);
response.addCookie(myCookie[i]);
                  }
                response.sendRedirect(url);
                 return;
                }
      /*
         if(sort.equals("MidTop"))
         {
                response.sendRedirect("/course/magazine/mid_top_list.jsp");         }
                if(sort.equals("MidDown"))
         {
                response.sendRedirect("/course/magazine/mid_down_list.jsp");         }
          if(sort.equals("AdvTop"))
         {
                response.sendRedirect("/course/magazine/adv_top_list.jsp");         }
          if(sort.equals("AdvDown"))
         {
                response.sendRedirect("/course/magazine/adv_down_list.jsp");         }
response.setContentType("text/html");
PrintWriter out = response.getWriter();
String title = "Searching the Web";
String heading;
Integer accessCount = new Integer(0);;
if (session.isNew()) {
heading = "Welcome, Newcomer";
} else {
heading = "Welcome Back";
Integer oldAccessCount =
// 在Servlet API 2.2中使用getAttribute而不是getValue
(Integer)session.getValue("accessCount");
if (oldAccessCount != null) {
accessCount =
new Integer(oldAccessCount.intValue() + 1);
}
}                */
  }
  /**Process the HTTP Post request*/
  public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    response.setContentType(CONTENT_TYPE);
    PrintWriter out = response.getWriter();
    out.println("<html>");
    out.println("<head><title>SessionServlet</title></head>");
    out.println("<body>");
    out.println("<p>The servlet has received a POST. This is the reply.</p>");
    out.println("</body></html>");
  }
  /**Process the HTTP Put request*/
  public void doPut(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
  }
  /**Process the HTTP Delete request*/
  public void doDelete(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
  }
  /**Clean up resources*/
  public void destroy() {
  }
}