一，通过session的关闭浏览器销毁，和使用getAttribute设置session对象值来控制页面用户是否有权限进入。
1，以下是登陆页面的代码，使用表单提交数据给一个servlet进行数据的处理
2，创建一个名为User的servlet页面
在doget方法中创建session对象，使用setAttribute方法为其赋值，
package com.in;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
public class User extends HttpServlet {
/**
* Constructor of the object.
*/
public User() {
super();
}
/**
* Destruction of the servlet.
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}
/**
* The doGet method of the servlet.
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
HttpSession session=request.getSession();
session.setAttribute("user","yes");
request.getRequestDispatcher("default.jsp").forward(request, response);
}
/**
* The doPost method of the servlet.
*
* This method is called when a form has its tag value method equals to post.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
}
/**
* Initialization of the servlet.
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
}
}
3，在登陆之后的页面中加入以下代码，以控制页面的访问权限。
放在
的下方，如果session为空或不等于上面赋的值，便跳转到登陆页面，重新为session赋值。<%
String aa=(String)session.getAttribute("user");
if(!"yes".equals(aa)||aa==null){
response.sendRedirect("longin.jsp");
}
%>