登录功能实现
登录功能流程图
1.编写登陆界面并设置为首页
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
<head lang="en">
<meta charset="UTF-8">
<title>系统登录 - 超市订单管理系统</title>
<link type="text/css" rel="stylesheet" href="${pageContext.request.contextPath }/css/style.css" />
<script type="text/javascript">
/* if(top.location!=self.location){
top.location=self.location;
} */
</script>
</head>
<body class="login_bg">
<section class="loginBox">
<header class="loginHeader">
<h1>超市订单管理系统</h1>
</header>
<section class="loginCont">
<form class="loginForm" action="${pageContext.request.contextPath }/login.do" name="actionForm" id="actionForm" method="post" >
<div class="info">${error}</div>
<div class="inputbox">
<label for="userCode">用户名：</label>
<input type="text" class="input-text" id="userCode" name="userCode" placeholder="请输入用户名" required/>
</div>
<div class="inputbox">
<label for="userPassword">密码：</label>
<input type="password" id="userPassword" name="userPassword" placeholder="请输入密码" required/>
</div>
<div class="subBtn">
<input type="submit" value="登录"/>
<input type="reset" value="重置"/>
</div>
</form>
</section>
</section>
</body>
</html>
将login.jsp设置为首页
在web.xml中将其设置为欢迎页
<welcome-file-list>
<welcome-file>login.jsp</welcome-file>
</welcome-file-list>
2.编写Dao层用户登陆的接口
package com.hao.dao.user;
import com.hao.pojo.User;
import java.sql.Connection;
import java.sql.SQLException;
public interface UserDao {
//得到要登陆的用户
public User getLoginUser(Connection connection, String userCode) throws SQLException;
}
3.编写Dao层用户登录接口的实现类
package com.hao.dao.user;
import com.hao.dao.BaseDao;
import com.hao.pojo.User;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
//实现接口的方法
public class UserDaoImpl implements UserDao {
//得到要登陆的用户
public User getLoginUser(Connection connection, String userCode) throws SQLException {
PreparedStatement preparedStatement = null;
ResultSet resultSet = null;
User user = null ;
if (connection!=null){
String sql = "select * from smbms_user where userCode=?";
Object[] params ={
userCode};
resultSet= BaseDao.execute(connection, preparedStatement, resultSet, sql, params);
if (resultSet.next()){
user = new User();
user.setId(resultSet.getInt("id"));
user.setUserCode(resultSet.getString("userCode"));
user.setUserName(resultSet.getString("userName"));
user.setUserPassword(resultSet.getString("userPassword"));
user.setGender(resultSet.getInt("gender"));
user.setBirthday(resultSet.getDate("birthday"));
user.setPhone(resultSet.getString("phone"));
user.setAddress(resultSet.getString("address"));
user.setUserRole(resultSet.getInt("userRole"));
user.setCreateBy(resultSet.getInt("createdBy"));
user.setCreateDate(resultSet.getDate("creationDate"));
user.setModifyBy(resultSet.getInt("modifyBy"));
user.setModifyDate(resultSet.getDate("modifyDate"));
BaseDao.closeResources(null,preparedStatement,resultSet);
}
}
return user;
}
}
4.业务层接口
package com.hao.service.user;
import com.hao.pojo.User;
public interface UserService {
public User login(String userCode,String password);
}
5.业务层接口实现类
package com.hao.service.user;
import com.hao.dao.BaseDao;
import com.hao.dao.user.UserDao;
import com.hao.dao.user.UserDaoImpl;
import com.hao.pojo.User;
import org.junit.Test;
import java.sql.Connection;
import java.sql.SQLException;
public class UserServiceImpl implements UserService{
//业务层都会调用Dao层，所以要引入Dao层;
private UserDao userDao;
public UserServiceImpl(){
userDao=new UserDaoImpl();
}
public User login(String userCode, String password) {
Connection connection = null;
User user = null;
try {
connection = BaseDao.getConnection();
//通过业务层调用对应的具体数据库操作
user=userDao.getLoginUser(connection,userCode);
} catch (SQLException throwables) {
throwables.printStackTrace();
}finally {
BaseDao.closeResources(connection,null,null);
}
return user;
}
6.编写Servlet
package com.hao.servlet.user;
import com.hao.pojo.User;
import com.hao.service.user.UserServiceImpl;
import com.hao.util.Constants;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
public class LoginServlet extends HttpServlet {
//Servlet：控制层，需要调用业务层代码
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//获取用户名和密码
//根据前端的name，输入关键字
String userCode = req.getParameter("userCode");
String userPassword = req.getParameter("userPassword");
UserServiceImpl userService = new UserServiceImpl();
User user = userService.login(userCode,userPassword);//将用户查出，如果数据库中没有，则为null
if (user!=null){
//数据库中有这个人
//把用户信息存入session
req.getSession().setAttribute(Constants.USER_SESSION,user);
//跳转到主页
resp.sendRedirect("jsp/frame.jsp");
}else {
//返回登录界面 数据库中没有该用户 或者账号密码错误
req.setAttribute("error","用户名或密码错误");
req.getRequestDispatcher("login.jsp").forward(req,resp);
}
}
}
在web.xml中注册
<!-- Servlet-->
<servlet>
<servlet-name>ServletLogin</servlet-name>
<servlet-class>com.hao.servlet.user.LoginServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>ServletLogin</servlet-name>
<url-pattern>/login.do</url-pattern>
</servlet-mapping>
测试访问
输入正确账号密码后
时间乱码 后面加个过滤器再处理
输入错误账号密码后
登录框架基本完成