上一篇文章
https://www.nasuiyile.cn/70.html
上一篇文章实现了hibernate的配置
现在来看看hibernate的基本使用吧,将上篇文章的一些常用方法封装了工具类
HibernateUtil
package com.myxq.utils;

import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;

public class HibernateUtil {
    public static final SessionFactory sessionFactory;
    static{
        //加载配置文件,如果不传参的话默认是传这个参数
        Configuration configure = new Configuration().configure("hibernate.cfg.xml");
        //创建seessionFactory jdbc连接池
        //创建session,session并不是轻量级的,一般情况下,一个项目用一个sessionFactory就够了
        // ,需要操作多个数据库,可以为每个数据库指定一个SessionFactory
        //内部维护了Hibernate的连接池和二级缓存
        sessionFactory =configure.buildSessionFactory();
    }
    public static Session openSession(){
        Session session=sessionFactory.openSession();
        return session;
    }
}

接下来是增删改查(curd的实现方法)
package com.myxq.test;

import com.myxq.domain.Customer;
        import com.myxq.utils.HibernateUtil;
        import org.hibernate.Session;
        import org.hibernate.SessionFactory;
        import org.hibernate.Transaction;
        import org.hibernate.cfg.Configuration;
        import org.hibernate.query.Query;
        import org.junit.Test;

        import java.util.List;


public class HibernateTest {
    @Test
    public void test1(){//增
        Session session= HibernateUtil.openSession();

        Customer customer=new Customer();
        customer.setCust_name("myxq");
        customer.setCust_level("2");
        //保存,设置了id就是修改操作,没有设置id就是添加操作
        session.save(customer);
        //释放资源
        session.close();
    }
    @Test
    public void test2(){//查
        Session session= HibernateUtil.openSession();
        //查询id为1的数据
        Customer customer = session.get(Customer.class, 1L);
        System.out.println(customer);
        session.close();
    }
    @Test
    public void test3(){//改
        Session session= HibernateUtil.openSession();
        Transaction transaction=session.beginTransaction();
        //查询id为1的数据
        Customer customer = new Customer();
        customer.setCust_id(1L);
        customer.setCust_name("myxq_update2");
        session.update(customer);
        //提交事务
        transaction.commit();
        session.close();
    }
    @Test
    public void test4(){//删
        Session session= HibernateUtil.openSession();
        Transaction transaction=session.beginTransaction();
        //查询id为1的数据
        Customer customer = new Customer();
        customer.setCust_id(3L);
        session.delete(customer);

        //提交事务
        transaction.commit();
        session.close();
    }
    @Test
    public void test6(){//查询全部的记录
        Session session=HibernateUtil.openSession();
        Transaction transaction=session.beginTransaction();

        //查询所有的hql,后面的参数为类的全路径
        Query query = session.createQuery("from com.myxq.domain.Customer");
        List<Customer> list = query.list();
        for (Customer customer:list) {
            System.out.println(customer);
        }
        transaction.commit();
        session.close();
    }
}