代码

package com.good.domain;

public class User {

  private Integer id;

  private String username;

  private String password;

public Integer getId() {

return id;

}

public void setId(Integer id) {

this.id = id;

}

public String getUsername() {

return username;

}

public void setUsername(String username) {

this.username = username;

}

public String getPassword() {

return password;

}

public void setPassword(String password) {

this.password = password;

}

}

package com.good.controller;

import java.io.IOException;

import javax.servlet.ServletException;

import javax.servlet.annotation.WebServlet;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;

import com.good.domain.User;

import com.good.model.UserModel;

/**

* Servlet implementation class UserServlet

*/

@WebServlet("/UserServlet")

public class UserServlet extends HttpServlet {

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

try {

String username = request.getParameter("username");

String password = request.getParameter("password");

User user = new User();

user.setUsername(username);

user.setPassword(password);

UserModel userModel = new UserModel();

User existUser = userModel.login(user);

if(existUser == null) {

request.setAttribute("msg", "用户名或密码错误");

request.getRequestDispatcher("/login.jsp").forward(request, response);

}else {

request.getSession().setAttribute("exisetUser", existUser);

response.sendRedirect(request.getContextPath() + "/jsp/success.jsp");

}

} catch (Exception e) {

e.printStackTrace();

}

}

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

doGet(request, response);

}

}

package com.good.filter;

import java.io.IOException;

import javax.servlet.Filter;

import javax.servlet.FilterChain;

import javax.servlet.FilterConfig;

import javax.servlet.ServletException;

import javax.servlet.ServletRequest;

import javax.servlet.ServletResponse;

import javax.servlet.http.HttpServletRequest;

public class GenericEncodingFilter implements Filter{

@Override

public void destroy() {

// TODO Auto-generated method stub

}

@Override

public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)

throws IOException, ServletException {

HttpServletRequest req = (HttpServletRequest) request;

    MyHttpServletRequest myReq = new MyHttpServletRequest(req);

    chain.doFilter(myReq, response);

}

@Override

public void init(FilterConfig filterConfig) throws ServletException {

// TODO Auto-generated method stub

}

}

package com.good.filter;

import java.io.IOException;

import javax.servlet.Filter;

import javax.servlet.FilterChain;

import javax.servlet.FilterConfig;

import javax.servlet.ServletException;

import javax.servlet.ServletRequest;

import javax.servlet.ServletResponse;

import javax.servlet.http.HttpServletRequest;

import com.good.domain.User;

public class MyPrivilegeFilter implements Filter{

@Override

public void destroy() {

// TODO Auto-generated method stub

}

@Override

public void doFilter(ServletRequest request, ServletResponse response, FilterChain Chain)

throws IOException, ServletException {

  HttpServletRequest req = (HttpServletRequest) request;

  User existUser = (User) req.getSession().getAttribute("existUser");

  if(existUser == null) {

  req.setAttribute("msg", "您还没有登录！没有权限访问！");

  req.getRequestDispatcher("/login.jsp").forward(request, response);

  }else {

  Chain.doFilter(request,response);

  }

}

@Override

public void init(FilterConfig arg0) throws ServletException {

// TODO Auto-generated method stub

}

}