今日内容
1. 综合练习
1. 简单功能
1. 列表查询
2. 登录
3. 添加
4. 删除
5. 修改
2. 复杂功能
1. 删除选中
2. 分页查询
* 好处：
1. 减轻服务器内存的开销
2. 提升用户体验
3. 复杂条件查询
2. 登录
1. 调整页面，加入验证码功能
2. 代码实现
业务逻辑流程
- 设置编码
- 获取数据
- 验证码校验
- 封装user对象
- 调用service查询
- 判断是否登陆成功
LoginServlet
package cn.itcast.web.servlet;
import cn.itcast.domain.User;
import cn.itcast.service.UserService;
import cn.itcast.service.impl.UserServiceImpl;
import org.apache.commons.beanutils.BeanUtils;
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 javax.servlet.http.HttpSession;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.util.Map;
@WebServlet("/loginServlet")
public class LoginServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//1.设置编码
request.setCharacterEncoding("utf-8");
//2.获取数据
//2.1获取用户填写验证码
String verifycode = request.getParameter("verifycode");
//3.验证码校验
HttpSession session = request.getSession();
String checkcode_server = (String) session.getAttribute("CHECKCODE_SERVER");
session.removeAttribute("CHECKCODE_SERVER");//确保验证码一次性
if(!checkcode_server.equalsIgnoreCase(verifycode)){
//验证码不正确
//提示信息
request.setAttribute("login_msg","验证码错误！");
//跳转登录页面
request.getRequestDispatcher("/login.jsp").forward(request,response);
return;
}
Map<String, String[]> map = request.getParameterMap();
//4.封装User对象
User user = new User();
try {
BeanUtils.populate(user,map);
} catch (IllegalAccessException e) {
e.printStackTrace();
} catch (InvocationTargetException e) {
e.printStackTrace();
}
//5.调用Service查询
UserService service = new UserServiceImpl();
User loginUser = service.login(user);
//6.判断是否登录成功
if(loginUser != null){
//登录成功
//将用户存入session
session.setAttribute("user",loginUser);
//跳转页面
response.sendRedirect(request.getContextPath()+"/index.jsp");
}else{
//登录失败
//提示信息
request.setAttribute("login_msg","用户名或密码错误！");
//跳转登录页面
request.getRequestDispatcher("/login.jsp").forward(request,response);
}
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.doPost(request, response);
}
}
service层
UserService抽象接口
/**
* 用户管理的业务接口
*/
public interface UserService {
/**
* 查询所有用户信息
* @return
*/
public List<User> findAll();
/**
* 登录方法
* @param user
* @return
*/
User login(User user);
}
UserServiceImpl 实现service中UserService
public class UserServiceImpl implements UserService {
private UserDao dao = new UserDaoImpl();
@Override
public List<User> findAll() {
//调用Dao完成查询
return dao.findAll();
}
@Override
public User login(User user) {
return dao.findUserByUsernameAndPassword(user.getUsername(),user.getPassword());
}
dao层
UserDaoImpl实现UserDao
UserDao
/**
* 用户操作的DAO
*/
public interface UserDao {
public List<User> findAll();
User findUserByUsernameAndPassword(String username, String password);
}
UserDaoImpl
public class UserDaoImpl implements UserDao {
private JdbcTemplate template = new JdbcTemplate(JDBCUtils.getDataSource());
@Override
public List<User> findAll() {
//使用JDBC操作数据库...
//1.定义sql
String sql = "select * from user";
List<User> users = template.query(sql, new BeanPropertyRowMapper<User>(User.class));
return users;
}
@Override
public User findUserByUsernameAndPassword(String username, String password) {
try {
String sql = "select * from user where username = ? and password = ?";
User user = template.queryForObject(sql, new BeanPropertyRowMapper<User>(User.class), username, password);
return user;
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
}
前端页面login.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset="utf-8"/>
<meta http-equiv="X-UA-Compatible" content="IE=edge"/>
<meta name="viewport" content="width=device-width, initial-scale=1"/>
<title>管理员登录</title>
<!-- 1. 导入CSS的全局样式 -->
<link href="css/bootstrap.min.css" rel="stylesheet">
<!-- 2. jQuery导入，建议使用1.9以上的版本 -->
<script src="js/jquery-2.1.0.min.js"></script>
<!-- 3. 导入bootstrap的js文件 -->
<script src="js/bootstrap.min.js"></script>
<script type="text/javascript">
//切换验证码
function refreshCode(){
//1.获取验证码图片对象
var vcode = document.getElementById("vcode");
//2.设置其src属性，加时间戳
vcode.src = "${pageContext.request.contextPath}/checkCodeServlet?time="+new Date().getTime();
}
</script>
</head>
<body>
<div class="container" style="width: 400px;">
<h3 style="text-align: center;">管理员登录</h3>
<form action="${pageContext.request.contextPath}/loginServlet" method="post">
<div class="form-group">
<label for="user">用户名：</label>
<input type="text" name="username" class="form-control" id="user" placeholder="请输入用户名"/>
</div>
<div class="form-group">
<label for="password">密码：</label>
<input type="password" name="password" class="form-control" id="password" placeholder="请输入密码"/>
</div>
<div class="form-inline">
<label for="vcode">验证码：</label>
<input type="text" name="verifycode" class="form-control" id="verifycode" placeholder="请输入验证码" style="width: 120px;"/>
<a href="javascript:refreshCode();">
<img src="${pageContext.request.contextPath}/checkCodeServlet" title="看不清点击刷新" id="vcode"/>
</a>
</div>
<hr/>
<div class="form-group" style="text-align: center;">
<input class="btn btn btn-primary" type="submit" value="登录">
</div>
</form>
<!-- 出错显示的信息框 -->
<div class="alert alert-warning alert-dismissible" role="alert">
<button type="button" class="close" data-dismiss="alert" >
<span>×</span>
</button>
<strong>${login_msg}</strong>
</div>
</div>
</body>
</html>
