在hibernate使用Oracle的序列 hibernate orderby

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一、实体类

package com.po;

import java.math.BigDecimal;

/**

* Goods entity. @author MyEclipse Persistence Tools

*/

public class Goods implements java.io.Serializable {

// Fields

private String gid;

private String gname;

private BigDecimal gprice;

// Constructors

/** default constructor */

public Goods() {

}

/** minimal constructor */

public Goods(String gid) {

this.gid = gid;

}

/** full constructor */

public Goods(String gid, String gname, BigDecimal gprice) {

this.gid = gid;

this.gname = gname;

this.gprice = gprice;

}

// Property accessors

public String getGid() {

return this.gid;

}

public void setGid(String gid) {

this.gid = gid;

}

public String getGname() {

return this.gname;

}

public void setGname(String gname) {

this.gname = gname;

}

public BigDecimal getGprice() {

return this.gprice;

}

public void setGprice(BigDecimal gprice) {

this.gprice = gprice;

}

}

二、映射文件
关键看映射文件如何配置

<?xml version="1.0" encoding="utf-8"?>

<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"

"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<!--

Mapping file autogenerated by MyEclipse Persistence Tools

-->

<hibernate-mapping>

<class name="com.po.Goods" table="GOODS" schema="LILY">

<id name="gid" type="java.lang.String">

<column name="GID" length="30" />

<generator class="sequence" >

<param name="sequence">goods_seq</param>

</generator>

</id>

<property name="gname" type="java.lang.String">

<column name="GNAME" length="30" />

</property>

<property name="gprice" type="java.math.BigDecimal">

<column name="GPRICE" precision="22" scale="0" />

</property>

</class>

</hibernate-mapping>

三、配置文件

<?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">

<!-- Generated by MyEclipse Hibernate Tools. -->

<hibernate-configuration>

<session-factory>

<property name="dialect">

org.hibernate.dialect.Oracle9Dialect

</property>

<property name="connection.url">

jdbc:oracle:thin:@127.0.0.1:1521:orcl

</property>

<property name="connection.username">lily</property>

<property name="connection.password">m123</property>

<property name="connection.driver_class">

oracle.jdbc.driver.OracleDriver

</property>

<property name="myeclipse.connection.profile">

oracle.jdbc.driver.OracleDriver

</property>

<property name="show_sql">true</property>

<mapping resource="com/po/Goods.hbm.xml" />

</session-factory>

</hibernate-configuration>

四、hibernate自动生成的获取Session工具类

package com.test;

import org.hibernate.HibernateException;

import org.hibernate.Session;

import org.hibernate.cfg.Configuration;

/**

* Configures and provides access to Hibernate sessions, tied to the

* current thread of execution. Follows the Thread Local Session

* pattern, see {@link http://hibernate.org/42.html }.

*/

public class HibernateSessionFactory {

/**

* Location of hibernate.cfg.xml file.

* Location should be on the classpath as Hibernate uses

* #resourceAsStream style lookup for its configuration file.

* The default classpath location of the hibernate config file is

* in the default package. Use #setConfigFile() to update

* the location of the configuration file for the current session.

*/

private static String CONFIG_FILE_LOCATION = "/hibernate.cfg.xml";

private static final ThreadLocal<Session> threadLocal = new ThreadLocal<Session>();

private static Configuration configuration = new Configuration();

private static org.hibernate.SessionFactory sessionFactory;

private static String configFile = CONFIG_FILE_LOCATION;

static {

try {

configuration.configure(configFile);

sessionFactory = configuration.buildSessionFactory();

} catch (Exception e) {

System.err

.println("%%%% Error Creating SessionFactory %%%%");

e.printStackTrace();

}

}

private HibernateSessionFactory() {

}

/**

* Returns the ThreadLocal Session instance. Lazy initialize

* the <code>SessionFactory</code> if needed.

*

* @return Session

* @throws HibernateException

*/

public static Session getSession() throws HibernateException {

Session session = (Session) threadLocal.get();

if (session == null || !session.isOpen()) {

if (sessionFactory == null) {

rebuildSessionFactory();

}

session = (sessionFactory != null) ? sessionFactory.openSession()

: null;

threadLocal.set(session);

}

return session;

}

/**

* Rebuild hibernate session factory

*

*/

public static void rebuildSessionFactory() {

try {

configuration.configure(configFile);

sessionFactory = configuration.buildSessionFactory();

} catch (Exception e) {

System.err

.println("%%%% Error Creating SessionFactory %%%%");

e.printStackTrace();

}

}

/**

* Close the single hibernate session instance.

*

* @throws HibernateException

*/

public static void closeSession() throws HibernateException {

Session session = (Session) threadLocal.get();

threadLocal.set(null);

if (session != null) {

session.close();

}

}

/**

* return session factory

*

*/

public static org.hibernate.SessionFactory getSessionFactory() {

return sessionFactory;

}

/**

* return session factory

*

*session factory will be rebuilded in the next call

*/

public static void setConfigFile(String configFile) {

HibernateSessionFactory.configFile = configFile;

sessionFactory = null;

}

/**

* return hibernate configuration

*

*/

public static Configuration getConfiguration() {

return configuration;

}

}

五、测试

package com.test;

import java.math.BigDecimal;

import org.hibernate.Session;

import org.hibernate.Transaction;

import com.po.Goods;

public class Test {

/**

* @param args

*/

public static void main(String[] args) {

// TODO Auto-generated method stub

Session s=HibernateSessionFactory.getSession();

Transaction tx = s.beginTransaction();

tx.begin();

Goods g=new Goods();

g.setGname("bbb");

g.setGprice(new BigDecimal(2000));

s.save(g);

tx.commit();

}

}