package Jdbc;
import JdbcUtil.JDBCUtils;
import domain.user;
import java.sql.*;
import java.util.ArrayList;
import java.util.List;
public class JdbcUtilDemo1 {
public static void main(String[] args) {
List<user> list = new JdbcUtilDemo1().findAll2();
System.out.println(list);
System.out.println(list.size());
}
/*
演示JDBC工具类
*/
public List<user> findAll2() {
Connection connection = null;
Statement statement = null;
ResultSet resultSet = null;
List<user> list = null;
try {/*//1.注册驱动
Class.forName("com.mysql.cj.jdbc.Driver");
//2.获取连接
connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/eesy_mybatis?useSSL=false&serverTimezone=CTT","root","1799510625hgj");*/
connection = JDBCUtils.getConnection();
//3.定义sql
String sql = "select * from user";
//4.获取执行sql的对象
statement = connection.createStatement();
//5.执行sql
resultSet = statement.executeQuery(sql);
//6.遍历结果集,封装对象,装载集合
user user = null;
list = new ArrayList<user>();
while (resultSet.next()) {
int id = resultSet.getInt("id");
String username = resultSet.getString("username");
Date birthday = resultSet.getDate("birthday");
String sex = resultSet.getString("sex");
String address = resultSet.getString("address");
//创建user对象,并赋值
user = new user();
user.setId(id);
user.setUsername(username);
user.setBirthday(birthday);
user.setSex(sex);
user.setAddress(address);
//装载集合
list.add(user);
}
}catch (SQLException e){
e.printStackTrace();
}finally {
//释放资源
/* if(resultSet != null){
resultSet.close();
}
if(statement != null){
statement.close();
}
if(connection != null){
connection.close();
}*/
JDBCUtils.close(resultSet, statement, connection);
}
return list;
}
}