Hibernate3之Hello, Word程序


这个板块太冷清了，记得范智曾经转贴过一个网上的“史上最简单的Hibernate入门”，内容却是乱起八糟。

现在Falcon要开始使用Hibernate了，我就勉为其难，出个cauchy版本的“Hibernate3之Hello, Word程序”吧！

Hibernate运行时依赖于以下软件包：
cglib-full-2.0.2.jar
commons-collections-2.1.1.jar
commons-logging-1.0.4.jar
dom4j-1.5.jar
ehcache-0.9.jar
hibernate3.jar
jta.jar

使用Hibernate首先要定义主配置文件hibernate.cfg.xml，再定义数据库映射文件*.hbm.xml，编写或产生DAO类，最后使用DAO类。

其中数据库映射文件和DAO类在实践中有3种使用方法：
1. 全部手工编写
2. 编写数据库映射文件，使用Hibernate工具，产生DAO类
3. 编写DAO类，使用类似XDoclet的标签技术，产生数据库映射文件

为了简化流程，下面以第一种方法为例说明：

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

  <session-factory>
    <!--
    <property name="connection.datasource">java:comp/env/jdbc/mydb</property> 
    -->
    
    <property name="generate_statistics">true</property>
    
    <property name="dialect">org.hibernate.dialect.SQLServerDialect</property>      
    <property name="connection.driver_class">com.inet.tds.TdsDriver</property>  
    <property name="connection.pool_size">150</property>
    <property name="connection.url">jdbc:inetdae7:127.0.0.1:1433?database=pubs</property>    
    <property name="connection.username">Falcon </property>
    <property name="connection.password">Falcon</property>    
    
    <property name="show_sql">false</property>    
    
    <mapping resource="cauchy/Region.hbm.xml"/>
  </session-factory>
  
</hibernate-configuration>
[/code]

2. 数据库映射定义

[code]
< ? 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>
  
  <!-- table created by:
  	CREATE TABLE REGION ( RECORD_ID VARCHAR(64) PRIMARY KEY, NAME VARCHAR(64) NOT NULL, CODE VARCHAR(12) NOT NULL );
  -->
  <class name="cauchy.Region" table="REGION"> 
	  <id type="string" name="ID" column="RECORD_ID" length="64">
      <generator class="uuid.hex"/>
    </id>  
    
    <property type="string" name="name" column="NAME" length="64" not-null="true" unique="false"/>
    <property type="string" name="code" column="CODE" length="12" not-null="true" unique="true"/>
  </class>
  
</hibernate-mapping>
[/code]

3. 自动产生或者手工编写DAO对象
[code]
package cauchy;

import java.io.Serializable;

public class Region implements Serializable {
	
	private String id;
	private String code;
	private String name;
	
	/**
	 * @param id The id to set.
	 */
	public void setID(String id) {
		this.id = id;
	}
	
	/**
	 * @return Returns the id.
	 */
	public String getID() {
		return id;
	}
	
	/**
	 * @param code The code to set.
	 */
	public void setCode(String code) {
		this.code = code;
	}
	
	/**
	 * @return Returns the code.
	 */
	public String getCode() {
		return code;
	}
	
	/**
	 * @param name The name to set.
	 */
	public void setName(String name) {
		this.name = name;
	}
	
	/**
	 * @return Returns the name.
	 */
	public String getName() {
		return name;
	}
}
[/code]

4. 运行测试

[code]
package cauchy;

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

public class TestRegion {

	public static void main(String[] args) {
		SessionFactory sf = new Configuration().configure().buildSessionFactory();
		Session session = sf.openSession();

		long t = System.currentTimeMillis();
		
		Transaction tx = session.beginTransaction();		
		for(int i = 1000; i <= 9999; i++) {
			Region region = new Region();
			region.setCode("CODE_" + i);
			region.setName("NAME_" + i);		
			session.save(region);
		}		
		tx.commit();
		
		t = System.currentTimeMillis() - t;
		
		System.out.println("\nTotal Use " + t + " ms\n");

		session.close();
		sf.close();
	}
}
[/code]

5. 程序代码
它是用Hibernate3和Eclipse3开发的，打包为<a href="Hibernate3Test.zip">Hibernate3Test.zip</a>