使用Map和Set的集合映射，都可以配合1对多，但是其中还是有细微的差别，主要体现在一方的inverse属性上
数据库结构如下：
其中member表的team字段对应team的id
CREATE
TABLE
`member1` (
`id`
varchar
(
50
)
NOT
NULL
,
`name`
varchar
(
50
)
default
NULL
,
`age`
varchar
(
50
)
default
NULL
,
`teamRole`
varchar
(
50
)
default
NULL
,
`team`
varchar
(
50
)
default
NULL
,
PRIMARY
KEY
(`id`)
) ENGINE
=
InnoDB
DEFAULT
CHARSET
=
gb2312;
CREATE
TABLE
`team1` (
`id`
varchar
(
50
)
NOT
NULL
,
`name`
varchar
(
50
)
default
NULL
,
PRIMARY
KEY
(`id`)
) ENGINE
=
InnoDB
DEFAULT
CHARSET
=
gb2312;
持久话类（使用Set方式）
package
maponetomany;
public
class
Member
{
private
String id;
private
String name;
private
String teamRole;
private
Team team;
private
String age;
public
String getAge()
{
return
age;
}
public
void
setAge(String age)
{
this
.age
=
age;
}
public
String getName()
{
return
name;
}
public
void
setName(String name)
{
this
.name
=
name;
}
public
String getTeamRole()
{
return
teamRole;
}
public
void
setTeamRole(String teamRole)
{
this
.teamRole
=
teamRole;
}
public
String getId()
{
return
id;
}
public
void
setId(String id)
{
this
.id
=
id;
}
public
Team getTeam()
{
return
team;
}
public
void
setTeam(Team team)
{
this
.team
=
team;
}
}
package
maponetomany;
import
java.util.HashSet;
import
java.util.Map;
import
java.util.Set;
public
class
Team
{
private
String id;
private
String name;
private
Set members
=
new
HashSet();
public
String getId()
{
return
id;
}
public
void
setId(String id)
{
this
.id
=
id;
}
public
Set getMembers()
{
return
members;
}
public
void
setMembers(Set members)
{
this
.members
=
members;
}
public
String getName()
{
return
name;
}
public
void
setName(String name)
{
this
.name
=
name;
}
}
这是相应的HBM映射文件
<?
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 - Hibernate Tools
-->
<
hibernate-mapping
package
="maponetomany"
>
<
class
name
="Member"
table
="member1"
>
<
id
name
="id"
column
="id"
>
<
generator
class
="uuid.hex"
></
generator
>
</
id
>
<
property
name
="name"
column
="name"
/>
<
property
name
="age"
column
="age"
/>
<
property
name
="teamRole"
column
="teamRole"
/>
<
many-to-one
name
="team"
column
="team"
/>
</
class
>
</
hibernate-mapping
>
<?
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 - Hibernate Tools
-->
<
hibernate-mapping
package
="maponetomany"
>
<
class
name
="Team"
table
="team1"
>
<
id
name
="id"
column
="id"
>
<
generator
class
="uuid.hex"
></
generator
>
</
id
>
<
property
name
="name"
column
="name"
/>
<
set
name
="members"
inverse
="true"
cascade
="save-update"
>
<
key
column
="team"
/>
<
one-to-many
class
="Member"
/>
</
set
>
</
class
>
</
hibernate-mapping
>
以下是测试代码：
这里要注意的是，member的teamRole属性是通过javabean的set方式注入的，用Map实现时，则是作为map的index属性去注入，没有在代码中显示的调用set方法，这也是本文讨论的重点
public
static
void
main(String[] args)
{
Configuration cfg
=
new
Configuration();
cfg.configure();
SessionFactory sf
=
cfg.buildSessionFactory();
Session session
=
sf.openSession();
Transaction t
=
session.beginTransaction();
Team team
=
new
Team();
team.setName(
"
足球队-01
"
);
Member m1
=
new
Member();
m1.setName(
"
01队01号
"
);
m1.setAge(
"
22
"
);
m1.setTeam(team);
m1.setTeamRole(
"
中后卫
"
);
Member m2
=
new
Member();
m2.setName(
"
01队02号
"
);
m2.setAge(
"
33
"
);
m2.setTeam(team);
m2.setTeamRole(
"
守门员
"
);
team.getMembers().add(m1);
team.getMembers().add(m2);
session.save(team);
t.commit();
System.out.println(
"
success
"
);
}
运行结果如下：
Hibernate: insert into team1 (name, id) values (?, ?)
Hibernate: insert into member1 (name, age, teamRole, team, id) values (?, ?, ?, ?, ?)
Hibernate: insert into member1 (name, age, teamRole, team, id) values (?, ?, ?, ?, ?)
可以看到，两个表的数据都插入了，而且关联正确（member的team值为team表的id）
如果我们改成Map方式，则需要改变持久话类的代码和映射文件，如下：
持久话类变化不大，只不过是把Set换成Map,但映射文件变化较大
package
maponetomany;
