Hibernate教程(1) -配置文件

Hibernate 使得数据库访问变得轻松而简单，代码也更加易于维护。刚开始使用Hibernate时配置文件非常重要。

1. 创建数据库和表：

create database test;use test;create table product (    id int not null auto_increment,    name varchar(30),    price float,    primary key (id)) default charset=utf8;

2.创建实体类：

public class Product {    int id;    String name;    float price;    public int getId() {        return id;    }    public void setId(int id) {        this.id = id;    }    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public float getPrice() {        return price;    }    public void setPrice(float price) {        this.price = price;    }}

3.配置Product.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.jinlei.wang.bean.Product" table="product">        <id name="id" column="id">            <generator class="native"></generator>        </id>        <property name="name"></property>        <property name="price"></property>    </class></hibernate-mapping>

注：配置文件要放在resources文件夹内否则会在项目启动时提示错误：org.hibernate.boot.MappingNotFoundException: Mapping (RESOURCE) not found : .hbm.xml : origin(.hbm.xml)

4.配置hibernate.cfg.xml

<?xml version='1.0' encoding='utf-8'?><!DOCTYPE hibernate-configuration PUBLIC        "-//Hibernate/Hibernate Configuration DTD//EN"        "http://www.hibernate.org/dtd/hibernate-configuration-3.0.dtd"><hibernate-configuration>    <session-factory>        <!--显示执行的sql语句-->        <property name="show_sql">true</property>        <!--自动更新数据库的表结构，不需要手动创建表，hibernate会自动创建-->        <property name="hbm2ddl.auto">update</property>        <!--指定数据库连接串-->        <property name="connection.url">jdbc:mysql://localhost:3306/test</property>        <!--数据库驱动-->        <property name="connection.driver_class">com.mysql.jdbc.Driver</property>        <!--连接数据库用户名-->        <property name="connection.username">root</property>        <!--连接数据库用户密码-->        <property name="connection.password">pasword</property>        <!--映射文件-->        <mapping resource="Product.hbm.xml"></mapping>    </session-factory></hibernate-configuration>

5.测试结果

public class TestHibernate {    public static void main(String[] args) {        Configuration configuration = new Configuration();        configuration.configure();        SessionFactory sessionFactory = configuration.buildSessionFactory();        Session session = sessionFactory.openSession();        session.beginTransaction();        Product product = new Product();        product.setName("iphone8");        product.setPrice(7000);        session.save(product);        session.getTransaction().commit();        session.close();        sessionFactory.close();    }}