Hibernate简单使用

创建数据库

CREATE DATABASE IF NOT EXISTS `hibernate_day1` /*!40100 DEFAULT CHARACTER SET utf8 */ /*!80016 DEFAULT ENCRYPTION='N' */;
USE `hibernate_day1`;
-- 导出  表 hibernate_day1.t_user 结构
CREATE TABLE IF NOT EXISTS `t_user` (
  `id` int NOT NULL AUTO_INCREMENT,
  `username` varchar(50) NOT NULL DEFAULT '0',
  `password` varchar(30) NOT NULL DEFAULT '0',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8;

编写实体类

package org.ccit.com.domain;

/**
 * @program: Hibernate_01
 * @description
 * @author: LIANG
 * @create: 2021-02-06 12:22
 **/
public class User {
    private int uid;
    private String username;
    private String password;

    public int getUid() {
        return uid;
    }

    public void setUid(int uid) {
        this.uid = uid;
    }

    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;
    }
}

在实体类同级目录下创建实体类名.hbm.xml映射配置文件

<!DOCTYPE hibernate-mapping PUBLIC
        "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
<!--    name: 模型全名称
        table: 对应表名-->
    <class name="org.ccit.com.domain.User" table="t_user">
<!--        name:模型类属性名  column:表中的字段名-->
        <id name="uid" column="id">
<!--            generator：id的生成策略 native：如果是mysql数据库 id会自动增长-->
            <generator class="native"></generator>
        </id>
<!--        如果模型的属性和数据库的列明相同 可省略不写-->
        <property name="username"></property>
        <property name="password"></property>
    </class>
</hibernate-mapping>

创建hibernate.cfg.xml核心配置文件

<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
    <session-factory>
        <!-- 1、配置数据库连接的4个参数 -->
        <property name="hibernate.connection.driver_class">com.mysql.cj.jdbc.Driver</property>
<!--        <property name="hibernate.connection.url">jdbc:mysql://localhost:3306/hibernate_day1</property>-->
        <property name="hibernate.connection.url">jdbc:mysql:///hibernate_day1?serverTimezone=UTC&useSSL=false</property>
        <property name="hibernate.connection.username">root</property>
        <property name="hibernate.connection.password">123456</property>

        <!--  是否显示sql语句 -->
        <property name="show_sql">true</property>
        <!--  是否格式化sql语句 -->
        <property name="format_sql">true</property>
        <!--  是否自动提交事务 -->
        <property name="hibernate.connection.autocommit">true</property>

        <!-- 2、配置JavaBean与表的映射文件 -->
        <mapping resource="org/ccit/com/domain/User.hbm.xml"/>
    </session-factory>
</hibernate-configuration>

编写Test类测试

import org.ccit.com.domain.User;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import org.hibernate.classic.Session;
import org.junit.Test;

import java.sql.Connection;

/**
 * @program: Hibernate_01
 * @description
 * @author: LIANG
 * @create: 2021-02-06 13:09
 **/
public class HibernateTest01 {
    @Test
    public void test01() {
        //保存用户数据
        //1 获取核心配置文件对象 默认是加载src下的hibernate.cfg.xml文件
        Configuration configure = new Configuration().configure();
        //2 创建会话工厂
        SessionFactory sessionFactory = configure.buildSessionFactory();
        //创建会话
        Session session = sessionFactory.openSession();
        //开启事务
        Transaction transaction = session.getTransaction();
        transaction.begin();
        //保存 直接把对象保存到数据库
        User user = new User();
        user.setUsername("LIANG");
        user.setPassword("2233");
        session.save(user);
        //4 提交事务
        transaction.commit();
        //5 关闭会话
        session.close();
        //6 关闭工厂
        sessionFactory.close();
    }
}