单向一对多关系映射：
一个房间对应多个使用者，也就是Room實例知道User實例的存在，而User實例則沒有意識到Room實例。
用户表：
package onlyfun.caterpillar;
public class User {
private Long id;
private String name;
public User() {}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
在room类中，是直接把用户作为一个对象直接存进room表中，其中user对象的类型是Set
room类：
package onlyfun.caterpillar;
import java.util.Set;
public class Room {
private Long id;
private String address;
private Set users;
public Room() {}
public Long getId() {
return id;
}
public void setId(Long id) {
this.id = id;
}
public String getAddress() {
return address;
}
public void setAddress(String address) {
this.address = address;
}
public Set getUsers() {
return users;
}
public void setUsers(Set users) {
this.users = users;
}
public void addUser(User user) {
users.add(user);
}
public void removeUser(User user) {
users.remove(user);
}
}
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="onlyfun.caterpillar.User" table="user">
<id name="id" column="id">
<generator class="native"/>
</id>
<property name="name" column="name"/>
</class>
</hibernate-mapping>
使用<one-to- many>标签配置一对多：
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="onlyfun.caterpillar.Room" table="room">
<id name="id" column="id">
<generator class="native"/>
</id>
<property name="address"
column="address"
type="java.lang.String"/>
<set name="users" table="user" cascade="all">
<key column="room_id"/>
<one-to-many class="onlyfun.caterpillar.User"/>
</set>
</class>
</hibernate-mapping>
接著您可以如下儲存物件：
原文：http://www.cnblogs.com/liaoyanglong/p/6606148.html