create database if not exists `sampledb`;
use `sampledb`;
/*table structure for table `sampledb`.`personinfo` */
drop table if exists `sampledb`.`room`;
create table room (
room_id int not null auto_increment,
address varchar(32) not null default '',
primary key (room_id)
) type=innodb;
create database if not exists `sampledb`;
use `sampledb`;
/*table structure for table `sampledb`.`personinfo` */
drop table if exists `sampledb`.`user`;
create table user (
user_id int not null auto_increment,
name varchar(16) not null default '',
room_id int not null,
index (room_id),
foreign key (room_id) references room(room_id),
primary key (user_id)
) type=innodb;
二、User.java
package com.tanm.test;
publicclass User {
privatelongid;
private String name;
private Room room;
publiclong getId() {
returnid;
}
publicvoid setId(long id) {
this.id = id;
}
public String getName() {
returnname;
}
publicvoid setName(String name) {
this.name = name;
}
public Room getRoom() {
returnroom;
}
publicvoid setRoom(Room room) {
this.room = room;
}
}
三?span style="font-size: 10pt">User.hbm.xml
<?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">
<hibernate-mapping>
<class name="com.tanm.test.User" table="user">
<id name="id" column="user_id" type="long">
<generator class="increment"/>
</id>
<property name="name" column="name" type="string" not-null="true" />
<many-to-one name="room" column="room_id" class="com.tanm.test.Room" />
</class>
</hibernate-mapping>
四、Room.java
package com.tanm.test;
import java.util.HashSet;
import java.util.Set;
publicclass Room {
privatelongid;
private String address;
private Set users = new HashSet();
public String getAddress() {
returnaddress;
}
publicvoid setAddress(String address) {
this.address = address;
}
publiclong getId() {
returnid;
}
publicvoid setId(long id) {
this.id = id;
}
public Set getUsers() {
returnusers;
}
publicvoid setUsers(Set users) {
this.users = users;
}
}
五、Room.hbm.xml
<?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">
<hibernate-mapping>
<class name="com.tanm.test.Room" table="room">
<id name="id" column="room_id" unsaved-value="0">
<generator class="increment"/>
</id>
<property name="address" column="address" type="string" not-null="true" />
<set name="users" table="user" inverse="true" cascade="all">
<key column="room_id"/>
<one-to-many class="com.tanm.test.User"/>
</set>
</class>
</hibernate-mapping>
六、Test.java
package com.tanm.test;
import org.hibernate.*;
import org.hibernate.cfg.*;
publicclass Test {
publicstaticvoid main(String[] args) throws HibernateException {
SessionFactory sessionFactory = new Configuration().configure()
.buildSessionFactory();
Room room = new Room();
room.setAddress("China_xi'an");
User user1 = new User();
user1.setName("111");
User user2 = new User();
user2.setName("222");
user1.setRoom(room);
user2.setRoom(room);
room.getUsers().add(user1);
room.getUsers().add(user2);
Session session = sessionFactory.openSession();
Transaction tx = session.beginTransaction();
session.save(room);
tx.commit();
session.close();
sessionFactory.close();
}
}
成功q行后的l果Q?/span>
Hibernate: insert into room (address, room_id) values (?, ?)
Hibernate: insert into user (name, room_id, user_id) values (?, ?, ?)
Hibernate: insert into user (name, room_id, user_id) values (?, ?, ?)]]>
Database:mysql
drop database if exists SAMPLEDB;
create database hello;
use hello;
create table CUSTOMERS (
ID int not null primary key,
NAME varchar(15) not null,
PASSWORD varchar(8) not null
);
2。在eclipse 中新建工E?/span>hbtest
3。在src中新?/span>package hbm
4。新?/span>pojoc?/span>Customer
package hbm;
public class Customer {
private int id;
private String name;
private String password;
/**
* @return Returns the id.
*/
public int getId() {
return id;
}
/**
* @param id
* The id to set.
*/
public void setId(int id) {
this.id = id;
}
/**
* @return Returns the name.
*/
public String getName() {
return name;
}
/**
* @param name
* The name to set.
*/
public void setName(String name) {
this.name = name;
}
/**
* @return Returns the password.
*/
public String getPassword() {
return password;
}
/**
* @param password
* The password to set.
*/
public void setPassword(String password) {
this.password = password;
}
//constructor
public Customer() {
}
}
5。?/span>myeclipse插g建立hibernate.cfg.xml 位于src目录?/span>
<?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.MySQLDialect</property>
<property name="connection.driver_class">com.mysql.jdbc.Driver</property>
<property name="connection.url">jdbc:mysql://127.0.0.1:3306/hello</property>
<property name="myeclipse.connection.profile">hbmysql</property>
<property name="connection.username">root</property>
<property name="connection.password">123</property>
<mapping resource="hbm/Customer.hbm.xml" />
</session-factory>
</hibernate-configuration>
6。在hbm package内新?/span>Customer.hbm.xml
<?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">
<!-- Generated by MyEclipse Hibernate Tools. -->
<hibernate-mapping>
<class name="hbm.Customer" table="CUSTOMERS">
<id name="id" column="ID" type="int">
<generator class="increment"/>
</id>
<property name="name" column="NAME" type="string" not-null="true"/>
<property name="password" column="PASSWORD" type="string" not-null="true"/>
</class>
</hibernate-mapping>
7。?/span>hibernate操作数据?/span>
package hbm;
import org.hibernate.*;
import org.hibernate.cfg.*;
import java.util.Iterator;
import java.util.List;
public class Hbmain {
public static SessionFactory sessionFactory;//数据存储?/span>
static {
try {
Configuration config = new Configuration().configure();
sessionFactory = config.buildSessionFactory();
} catch (Exception e) {
e.printStackTrace();
}
}
/*
* 一?/span>customer对象存入database
* @Customer customer Object
*/
public void saveCustomer(Customer ct) {
Session session = sessionFactory.openSession();
Transaction tx = null;
try {
tx = session.beginTransaction();
session.save(ct);
tx.commit();
} catch (Exception e) {
tx.rollback();
e.printStackTrace();
} finally {
session.close();
}
}
/*
* 查找所有的customer object
*/
public void findAll() {
Session session = sessionFactory.openSession();
Transaction tx = null;
try {
tx = session.beginTransaction();
List customers = session.createQuery(
"from Customer as c order by c.name asc").list();
Iterator it = customers.iterator();
System.out.println("append:"+customers.size());
while(it.hasNext())
{
Customer c = (Customer)it.next();
System.out.println("ID:" + c.getId());
System.out.println("Name:" + c.getName());
System.out.println("Pass:" + c.getPassword());
}
tx.commit();
} catch (Exception e) {
tx.rollback();
} finally {
session.close();
}
}
/*
* 修改customer Name
* @name
*/
public void loadUpdate(int customer_id, String name) {
Session session = sessionFactory.openSession();
Transaction tx = null;
try {
tx = session.beginTransaction();
Customer c = (Customer) session.load(Customer.class, customer_id);
c.setName(name);
tx.commit();
} catch (Exception e) {
if (tx != null) {
tx.rollback();
}
e.printStackTrace();
} finally {
session.close();
}
}
/*
* 试以上的方?/span>
* save() find() update()
*/
public void test()
{
Customer ct = new Customer();
//ct.setId(5);
ct.setName("buaa");
ct.setPassword("5768");
this.saveCustomer(ct);
this.findAll();
this.loadUpdate(ct.getId(),"phop");
}
public static void main(String[] args) {
// TODO Auto-generated method stub
Hbmain hb = new Hbmain();
hb.test();
sessionFactory.close();
}
}
参考书是孙卫琴?lt;_NHibernate>
hibernate 3 + mysql 5.0
1 书上的例子第2?初始?hibernate Configuration实例
代码如下Q?/span>
Configuration config = new Configuration();
config.addClass("Customer.class");
SessionFactory sessionfactory = config.buildSessionFactory();
配置文g?hibernate.properties
q行出错 Q提CZؓ
org.hibernate.HibernateException: database product name cannot be null
昄是配|文件的问题
我用的配|文件是 hibernate.cfg.xml
修改Z下代?成功q行
Configuration config = new Configuration().configure();
SessionFactory sessionFactory = config.buildSessionFactory();
原因:使用了xm作ؓ配置文gQ而没有选择properties文g,应该使用new Configuration().config();
2 书上例子W六章一对多映射
customer.hbm.xml ?/span>
原代码ؓ
<hibernate-mapping>
<class name="demo1.Customer" table="CUSTOMERS">
<id name="id" type="long" column="ID">
<generator class="increment" />
</id>
<property name="name" type="string">
<column name="NAME" length="15" />
</property>
</class>
</hibernate-mapping>
此时执行其Business.java?/span>
Customer customer = (Customer) session.load(Customer.class,
new Long(customer_id));
出现如下错误
1 Exception in thread "main" java.lang.NullPointerException
2 at org.hibernate.tuple.AbstractTuplizer.createProxy(AbstractTuplizer.java:249)
3 at org.hibernate.persister.entity.BasicEntityPersister.createProxy(BasicEntityPersister.java:2831)
4 at org.hibernate.event.def.DefaultLoadEventListener.createProxyIfNecessary(DefaultLoadEventListener.java:218)
5 at org.hibernate.event.def.DefaultLoadEventListener.proxyOrLoad(DefaultLoadEventListener.java:163)
6 at org.hibernate.event.def.DefaultLoadEventListener.onLoad(DefaultLoadEventListener.java:79)
7 at org.hibernate.impl.SessionImpl.load(SessionImpl.java:603)
8 at org.hibernate.impl.SessionImpl.load(SessionImpl.java:596)
修改?/span>
<hibernate-mapping default-lazy="false">
<class name="demo1.Customer" table="CUSTOMERS">
<id name="id" type="long" column="ID">
<generator class="increment" />
</id>
<property name="name" type="string">
<column name="NAME" length="15" />
</property>
</class>
</hibernate-mapping>
问题解决
原因在于Q?Hibernate 3.0 与Hibernate2.1的源代码是不兼容?br /> 在Hibernate2.1中，lazy属性的默认gؓ“false”Q而在Hibernate3.0中，lazy属性的默认gؓ“true”?/span>
]]>