Specific Implementation and Analysis Dao layer

dao level code

package com.dao.Impl;
import com.dao.IUserDao;
import com.domain.User;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import java.util.List;
public class UserDaoImpl implements IUserDao{
    private SqlSessionFactory factory;
    public UserDaoImpl(SqlSessionFactory factory){
        this.factory = factory;
    }
    public List<User> findAll() {
        //1.使用工厂创建SqlSession对象
        SqlSession session = factory.openSession();
        //2.使用session执行查询所有方法
        List<User> users = session.selectList("com.dao.IUserDao.findAll");
        session.close();
        //3.返回查询结果
        return users;
    }
}

package com.dao;
import com.domain.User;
import org.apache.ibatis.session.SqlSession;
import java.util.List;
public interface IUserDao {
    //查询所有操作
    List<User> findAll();
}

Diagram