11.18

11.18
用servlet+jsp实现了数据库用户登入，明天搞商品查询案例
servlet数据库链接和jsp页面测试
关于重定向和请求转发的一些测试
login.jsp
<%@ page language=“java” contentType=“text/html; charset=utf-8”
pageEncoding=“utf-8”%>

用户名: 密码: loginServlet.java //关于业务逻辑的处理以及重定向转发的测试 package service;

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.RequestDispatcher;
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 Dao.LoginDao;
import entity.User;

/**

• Servlet implementation class LoginServlet
  */
  @WebServlet("/LoginServlet")
  public class LoginServlet extends HttpServlet {
  private static final long serialVersionUID = 1L;

  /**

  • @see HttpServlet#HttpServlet()
    */
    public LoginServlet() {
    super();
    // TODO Auto-generated constructor stub
    }

  /**

  • @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
    */
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    //response.getWriter().append("Served at: ").append(request.getContextPath());
    request.setCharacterEncoding(“utf-8”);
    response.setCharacterEncoding(“utf-8”);
    response.setContentType(“text/html;charset=utf-8”);
    PrintWriter out =response.getWriter();

    String name = request.getParameter(“username”);
    String password =request.getParameter(“password”);
    out.println(name+"."+password);
    /登陆成功时，关于重定向的测试/
    /*if(“张三”.equals(name)&&“1234”.equals(password))
    response.sendRedirect("/servertext/NewFile.jsp");
    */
    /登陆时，关于请求转发的测试/
    if(“张三”.equals(name)&&“1234”.equals(password)){
    RequestDispatcher dispatcher =request.getRequestDispatcher("/NewFile.jsp");
    dispatcher.forward(request,response);
    }
    LoginDao dao =new LoginDao();
    User user = dao.check(name, password);
    if(user.getName()==null){
    out.print(“登陆失败”);
    }else{
    out.print(“登录成功”);
    }
    }

  /**

  • @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
    */
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    doGet(request, response);
    }

}