Hibernate简单例子

Hibernate是一个比较流行的持久层框架，它对JDBC进行轻量级的封装，Hibernate可以在应用EJB的J2EE架构中取代CMP，完成数据持久化的重任。

我们写一个简单的Demo,Hibernate操作Access数据库。

1、首先建立工程导入hibernate3.0的Jar包。

2、编写Hibernate工具类和配置文件

package persistence;

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

public class HibernateUtil {
	private static final SessionFactory sessionFactory;
	static {
		try {
			sessionFactory = new Configuration().configure()
					.buildSessionFactory();
		} catch (HibernateException ex) {
			throw new RuntimeException("Exception building SessionFactory:"
					+ ex.getMessage(), ex);
		}
	}

	public static Session currentSession() throws HibernateException {
		Session s = sessionFactory.openSession();
		return s;
	}

	public static void closeSession(Session s) {
		if (s != null) {
			s.close();
		}
	}

}

hibernate.cfg.xml

<?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="show_sql">true</property>
        <property name="connection.driver_class">
            sun.jdbc.odbc.JdbcOdbcDriver
        </property>
        <property name="connection.url">
	    <!--连接数据库的URL，-->
	    jdbc:odbc:driver={Microsoft Access Driver (*.mdb)};DBQ=D:\student.mdb
        </property>
        <property name="dialect">              <!--指定连接的语言-->
            org.hibernate.dialect.SQLServerDialect
        </property>
        <mapping resource="Student.hbm.xml" /><!--映射Student这个资源-->
        
        </session-factory>
        
</hibernate-configuration>

Student.hbm.xml

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping
    PUBLIC "-//Hibernate/Hibernate Mapping DTD//EN"
    "http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<hibernate-mapping>
    <class name="model.Student" table="student"><!--把类和数表关联起来-->
        <id name="id" unsaved-value="null">    <!--id的产生方式是uuid.hex-->
            <generator class="uuid.hex" />
		</id>
		<property name="cardId"  type="string"  /><!--映射学号-->
		<property name="name"   type="string" /><!--映射名字-->
		<property name="age" type="int" />     <!--映射学生岁数-->
		
    </class>
</hibernate-mapping>

模型Student.java

package model;

public class Student {
	private String id;
	private String name;
	private String cardId;
	private int age;

	public String getId() {
		return id;
	}

	public void setId(String id) {
		this.id = id;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public String getCardId() {
		return cardId;
	}

	public void setCardId(String cardId) {
		this.cardId = cardId;
	}

	public int getAge() {
		return age;
	}

	public void setAge(int age) {
		this.age = age;
	}
}

dao StudentDao接口

package dao;

import java.util.List;

import model.Student;

public interface StudentDao {
	/*  创建新的学生对象   */
	public void createStudent(Student stu);
	/*  删除学生对象  */
	public void delStudent(String id);
	/*  更新学生对象   */
	public void modifyStudent(Student stu);
	/*  获得所有的学生列表 */
	public List<Student> getAllStudent();
	
}

dao实现类StudentDaoImpl

package dao.imp;

import java.util.List;

import model.Student;

import org.hibernate.HibernateException;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;

import persistence.HibernateUtil;
import dao.StudentDao;

public class StudentDaoImpl implements StudentDao {
	private Session session;

	@Override
	public void createStudent(Student stu) {
		try {
			session = HibernateUtil.currentSession();//开启连接
			Transaction tx = session.beginTransaction();//开启事务
			session.save(stu);
			tx.commit();//关闭事务
		} catch (HibernateException e) {
			e.printStackTrace();
		} finally {
			HibernateUtil.closeSession(session);//关闭连接
		}
	}

	@Override
	public void delStudent(String id) {
		try {
			session = HibernateUtil.currentSession();
			Transaction tx = session.beginTransaction();
			Student stu = (Student) session.get(Student.class, id);
			session.delete(stu);
			tx.commit();
		} catch (HibernateException e) {
			e.printStackTrace();
		} finally {
			HibernateUtil.closeSession(session);
		}
	}

	@Override
	public void modifyStudent(Student stu) {
		try {
			session = HibernateUtil.currentSession();
			Transaction tx = session.beginTransaction();
			session.update(stu);
			tx.commit();
		} catch (HibernateException e) {
			e.printStackTrace();
		} finally {
			HibernateUtil.closeSession(session);
		}
	}

	@Override
	public List<Student> getAllStudent() {
		List<Student> list = null;
		try {
			session = HibernateUtil.currentSession();
			Transaction tx = session.beginTransaction();
			Query q = session.createQuery("from Student");
			list = q.list();
			tx.commit();
		} catch (HibernateException e) {
			e.printStackTrace();
		} finally {
			HibernateUtil.closeSession(session);
		}
		return list;
	}

}

HibernateTest测试类:

package persistence;

import java.util.List;

import model.Student;
import dao.StudentDao;
import dao.imp.StudentDaoImpl;

public class HibernateTest {
	public static void main(String[] args) {
		StudentDao dao = new StudentDaoImpl();
		Student stu = new Student();
		stu.setAge(30);
		stu.setCardId("111111111");
		stu.setName("小明");
		/*-------------新增学生信息-------------------*/
		//dao.createStudent(stu);
		
	    List<Student> list = dao.getAllStudent();
		for(Student s:list){
			System.out.println(s.getId() + "" + s.getName() + "," + s.getCardId() + "," + s.getAge());
		}
		Student stu2 = (Student) list.get(0);
		stu2.setName("测试修改名称");
		stu2.setAge(600);
		//dao.modifyStudent(stu2);
		//dao.delStudent(stu2.getId());
	}
}

源码下载地址：http://download.csdn.net/detail/sydica/7035427