共计 6623 个字符，预计需要花费 17 分钟才能阅读完成。
src 层
cn.itcast.dao
UserDao.java
package cn.itcast.dao;
import cn.itcast.domain.User;
import cn.itcast.util.JDBCUtils;
import org.springframework.dao.DataAccessException;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
/**
- 操作数据库中 User 表的类
*/
public class UserDao {
// 声明 JDBCTemplate 对象共用
private JdbcTemplate template = new JdbcTemplate(JDBCUtils.getDataSource());
/**
* 登录方法
* @param loginUser 只有用户名和密码
* @return user 包含用户全部数据, 没有查询到，返回 null
*/
public User login(User loginUser){
try {
//1. 编写 sql
String sql = "select * from user where username = ? and password = ?";
//2. 调用 query 方法
User user = template.queryForObject(sql,
new BeanPropertyRowMapper<User>(User.class),
loginUser.getUsername(), loginUser.getPassword());
return user;
} catch (DataAccessException e) {e.printStackTrace();// 记录日志
return null;
}
}}
cn.itcast.domain
User.java
package cn.itcast.domain;
/**
- 用户的实体类
*/
public class User {
private int id;
private String username;
private String password;
private String gender;
public void setHehe(String gender){this.gender = gender;}
public String getHehe(){return gender;}
public int getId() {return id;}
public void setId(int 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;}
@Override
public String toString() {
return "User{" +
"id=" + id +
", username='" + username + '\'' +
", password='" + password + '\'' +
", gender='" + gender + '\'' +
'}';
}}
cn.itcast.test(测试类)
UserDaoTest.java
package cn.itcast.test;
import cn.itcast.dao.UserDao;
import cn.itcast.domain.User;
import org.junit.Test;
public class UserDaoTest {
@Test
public void testLogin(){User loginuser = new User();
loginuser.setUsername("superbaby");
loginuser.setPassword("123111");
UserDao dao = new UserDao();
User user = dao.login(loginuser);
System.out.println(user);
}}
BeanUtils.java
package cn.itcast.test;
import cn.itcast.domain.User;
import org.apache.commons.beanutils.BeanUtils;
import org.junit.Test;
import java.lang.reflect.InvocationTargetException;
public class BeanUtilsTest {
@Test
public void test(){User user = new User();
try {BeanUtils.setProperty(user,"hehe","male");
System.out.println(user);
String gender = BeanUtils.getProperty(user, "hehe");
System.out.println(gender);
} catch (IllegalAccessException e) {e.printStackTrace();
} catch (InvocationTargetException e) {e.printStackTrace();
} catch (NoSuchMethodException e) {e.printStackTrace();
}
}}
cn.itcast.until(工具类)
JDBCUtil.java
package cn.itcast.util;
import com.alibaba.druid.pool.DruidDataSourceFactory;
import javax.sql.DataSource;
import javax.xml.crypto.Data;
import java.io.IOException;
import java.io.InputStream;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Properties;
/**
- JDBC 工具类 使用 Durid 连接池
*/
public class JDBCUtils {
private static DataSource ds ;
static {
try {
//1. 加载配置文件
Properties pro = new Properties();
// 使用 ClassLoader 加载配置文件，获取字节输入流
InputStream is = JDBCUtils.class.getClassLoader().getResourceAsStream("druid.properties");
pro.load(is);
//2. 初始化连接池对象
ds = DruidDataSourceFactory.createDataSource(pro);
} catch (IOException e) {e.printStackTrace();
} catch (Exception e) {e.printStackTrace();
}
}
/**
* 获取连接池对象
*/
public static DataSource getDataSource(){return ds;}
/**
* 获取连接 Connection 对象
*/
public static Connection getConnection() throws SQLException {return ds.getConnection();
}}
cn.itcast.web(servlet 层)
servlet
LoginServlet.java
package cn.itcast.web.servlet;
import cn.itcast.dao.UserDao;
import cn.itcast.domain.User;
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 java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.util.Map;
@WebServlet(“/loginServlet”)
public class LoginServlet extends HttpServlet {
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
//1. 设置编码
req.setCharacterEncoding("utf-8");
/* //2. 获取请求参数
String username = req.getParameter("username");
String password = req.getParameter("password");
//3. 封装 user 对象
User loginUser = new User();
loginUser.setUsername(username);
loginUser.setPassword(password);*/
//2. 获取所有请求参数
Map<String, String[]> map = req.getParameterMap();
//3. 创建 User 对象
User loginUser = new User();
//3.2 使用 BeanUtils 封装
try {BeanUtils.populate(loginUser,map);
} catch (IllegalAccessException e) {e.printStackTrace();
} catch (InvocationTargetException e) {e.printStackTrace();
}
//4. 调用 UserDao 的 login 方法
UserDao dao = new UserDao();
User user = dao.login(loginUser);
//5. 判断 user
if(user == null){
// 登录失败
req.getRequestDispatcher("/failServlet").forward(req,resp);
}else{
// 登录成功
// 存储数据
req.setAttribute("user",user);
// 转发
req.getRequestDispatcher("/successServlet").forward(req,resp);
}
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {this.doGet(req,resp);
}}
SuccessServlet.java
package cn.itcast.web.servlet;
import cn.itcast.domain.User;
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 java.io.IOException;
@WebServlet(“/successServlet”)
public class SuccessServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// 获取 request 域中共享的 user 对象
User user = (User) request.getAttribute("user");
if(user != null){
// 给页面写一句话
// 设置编码
response.setContentType("text/html;charset=utf-8");
// 输出
response.getWriter().write("登录成功！"+user.getUsername()+", 欢迎您");
}
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {this.doPost(request,response);
}}
FailServlet.java
package cn.itcast.web.servlet;
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 java.io.IOException;
@WebServlet(“/failServlet”)
public class FailServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// 给页面写一句话
// 设置编码
response.setContentType("text/html;charset=utf-8");
// 输出
response.getWriter().write("登录失败，用户名或密码错误");
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {this.doPost(request,response);
}}
web 层
WEN-INF
lib
login.html
<!DOCTYPE html>
<html lang=”en”>
<head>
<meta charset="UTF-8">
<title>Title</title></head>
<body>
<form action="/day14_test/loginServlet" method="post">
用户名:<input type="text" name="username"> <br>
密码:<input type="password" name="password"><br>
<input type="submit" value="登录">
</form></body>
</html>