java的类似百度网盘项目

package web.controller; import java.io.IOException; import java.util.ArrayList; import java.util.List; import javax.servlet.ServletException; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import cn.domain.DB; import cn.domain.User; public class LoginServlet extends HttpServlet { public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String username = request.getParameter("username"); String password = request.getParameter("password"); boolean token = false; List<User> list = DB.getAll(); for(User DBuser:list) { if(DBuser.getUsername().equals(username)) { if(DBuser.getPassword().equals(password)) { { User user = (User) request.getSession().getAttribute("user"); if(user == null) { user = new User(username,password); } request.getSession().setAttribute("user", user); if(user.isLogin() == true) { request.setAttribute("message", "此帐号已经有人登录！！"); request.getRequestDispatcher("/message.jsp").forward(request, response); return; } user.setLogin(true); HttpSession session = request.getSession(); request.getSession().setAttribute("user",user ); String id = request.getSession().getId(); request.getSession().setAttribute("sessionid",id ); request.getRequestDispatcher("/welcome.jsp").forward(request, response); return ; } } else { request.setAttribute("message", "您输入的密码错误，请检查后登录！！"); request.getRequestDispatcher("/message.jsp").forward(request, response); return; } } } request.setAttribute("message", "该用户名还未注册，请检查后再登录！！"); request.getRequestDispatcher("/message.jsp").forward(request, response); return; /*for(User DBuser:list) { if(DBuser.getUsername().equals(username) && !DBuser.getPassword().equals(password)) { request.setAttribute("message", "您输入的密码错误，请检查后登录！！"); request.getRequestDispatcher("/message.jsp").forward(request, response); return; } if(DBuser.getUsername().equals(username) && DBuser.getPassword().equals(password)) { User user = new User(username,password); request.getSession().setAttribute("user",user ); request.getRequestDispatcher("/welcome.jsp").forward(request, response); return ; } } request.setAttribute("message", "您的用户名或密码错误！！"); request.getRequestDispatcher("/message.jsp").forward(request, response); return; */ } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request,response); } }