一个简单的 Hibernate 配置例子

大家学习Hibernate 的时候肯定会对它的配置文件感到困惑,首先,我们之所以需要使用到Hibernate,是因为它是一种数据库面向对象的方法,而非传统JDBC的面向关系,使用Hibernate技术,一般需要一个Pojo类(即普通的java类),这里就简单介绍一个单类User

import java.io.Serializable;

public class User implements Serializable
{
	//标识属性
	private int id;
	//用户名属性
	private String userName;
	//密码属性
	private String password;
	//电子邮件属性
	private String email;

	public void setId(int id)
	{
		this.id = id;
	}
	public int getId()
	{
		 return this.id;
	}

	public void setUserName(String user)
	{
		this.userName = user;
	}
	public String getUserName()
	{
		 return this.userName;
	}

	public void setPassword(String pass)
	{
		this.password = pass;
	}
	public String getPassword()
	{
		 return this.password;
	}

	public void setEmail(String email)
	{
		this.email = email;
	}
	public String getEmail()
	{
		 return this.email;
	}

}

然后,要实现ORM(Object Relational Mapping )需要一个 以 ".hbm.xml"后缀的映射文件,这样就可以实现对象映射关系.这里我的数据库使用的是Orale
User.hbm.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC 
	"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
	"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping 
	package="com.chen.model">
	<class name="User" table="user_table">
		<id name="id" column="user_id">
			<generator class="increment"/>
		</id>
		<property name="userName"
		         column="user_name"
		         not-null="true"
		         length="100"/>
		
		<property name="password" 
			not-null="true"
			length="100"
			column="user_pwd"/>
		
		<property name="email" 
			column="user_mail"
			length="100"/>		
	</class>	
</hibernate-mapping>

很自然的,要连接数据库,要一些数据库的配置 "Hibernate.cfg.xml" 在配置文件中需要配置一些用户名,密码,数据库驱动,连接串,映射文件

<?xml version='1.0' encoding='utf-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<hibernate-configuration>

<session-factory>
	<property name="show_sql">true</property>

	<!-- Drop and re-create the database schema on startup -->
	<property name="hbm2ddl.auto">update</property>
	<property name="connection.driver_class">
		oracle.jdbc.driver.OracleDriver
	</property>
	<property name="connection.url">
		jdbc:oracle:thin:@localhost:1521:ORA
	</property>
	<property name="connection.username">chenlei</property>
	<property name="connection.password"></property>
	<property name="dialect">
		org.hibernate.dialect.Oracle9Dialect
	</property>
	<mapping resource="com/test/hbm/User.hbm.xml" />
	
</session-factory>
</hibernate-configuration>

这样子,基本的配置就已经完成了