对象创建，表结构就会自动生成

1.目录

2.User.java

package com.itheima.domain;

public class User {

    private Integer id;
    private String name;
    private Integer age;
    public Integer getId() {
        return id;
    }
    public void setId(Integer id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public Integer getAge() {
        return age;
    }
    public void setAge(Integer age) {
        this.age = age;
    }
    
}

3.User.hbm.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-mapping PUBLIC 
    "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
    "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
    <class name="com.itheima.domain.User" table="t_user">
        <id name="id" column="id">
            <!--  
                increment：获取主键的最大值，进行+1，做为主键
            -->
            <generator class="native"/>
        </id>
        <property name="name" column="name" length="30"/>
        <property name="age" column="age"/>
    </class>
</hibernate-mapping>    

 

4.Hibernate.cfg.xml配置文件

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE hibernate-configuration PUBLIC
    "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
    "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd">

<hibernate-configuration>
    <!-- 记住:先配置sessionFactoryy -->
    
    <session-factory>
        <!-- 必须的配置 -->
        <!-- 配置连接数据库的基本的信息: -->
        <property name="hibernate.connection.driver_class">com.mysql.jdbc.Driver</property>
        <property name="hibernate.connection.url">jdbc:mysql:///hibernate_day02</property>
        <property name="hibernate.connection.username">root</property>
        <property name="hibernate.connection.password">123456</property>
        
        <!-- 数据库的方言: -->
        <property name="hibernate.dialect">org.hibernate.dialect.MySQLDialect</property>
        <!-- 可选配置 -->
        <!-- 显示SQL语句，在控制台显示 -->
        <property name="hibernate.show_sql">true</property>
        <!-- 格式化SQL语句 -->
        <property name="hibernate.format_sql">true</property>
        <!-- 生成数据库的表结构 
            update：如果没有表结构，创建表结构。如果存在，不会创建，添加数据
        -->
        <property name="hibernate.hbm2ddl.auto">update</property>
        
        <!-- 设置数据库的隔离级别，就使用默认值就OK 
        <property name="hibernate.connection.isolation">4</property>
        -->
        
        <!-- 开启绑定本地的session -->
        <property name="hibernate.current_session_context_class">thread</property>
        
        <!-- 映射配置文件，需要引入映射的配置文件 -->
        <mapping resource="com/itheima/domain/User.hbm.xml"/>
        

    </session-factory>
</hibernate-configuration>

5.运行HibernateUtils.java的主方法，就可以直接通过对象在数据库中简历数据表

package com.itheima.utils;

import javax.servlet.jsp.jstl.core.Config;

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

/*
 * Hibernate框架的工具
 * @author chenyanlong
 */
public class HibernateUtils {

    //Curl+shift+x
    private static final Configuration CONFIG;
    private static final SessionFactory FACTORY;
    
    //编写静态代码
    static {
        //加载配置文件
        CONFIG =new Configuration().configure();
        //构造工厂
        FACTORY=CONFIG.buildSessionFactory();
    }
    
    /*
     * 从工厂获取Session对象
     * @return
     */
    public static Session getSession() {
        return FACTORY.openSession();
        
    }
    
    
    /**
     * // 从ThreadLocal类中获取到session的对象
     * @return
     */
    public static Session getCurrentSession(){
        return FACTORY.getCurrentSession();
    }
    public static  void main(String[] args) {
        //调用获取session的方法
        getSession();
    }
}

 

6.显示效果