这种数据库结果如何用hibernate实现?

[lxf9501]

表一：plu : storeID,itemNumber是key
表二：ord : storeID,itemNumber,requestNumber是key
其中 前两个key可以关联
如何用hibernate来描述这个结构？？

[lxf9501]

哪位能帮帮忙？？？

[thriller75]

用comsite-id来表示。不过都不太推崇这种设计.

<composite-id name="comp_id" class="pK">
<meta attribute="class-description" inherit="false">
@hibernate.id
generator-class="assigned"
</meta>
<key-property
name="examId"
column="iExamId"
type="java.lang.Integer"
length="4"
>
<meta attribute="field-description">
@hibernate.property
column="iExamId"
length="4"
</meta>
</key-property>
<key-property
name="studentId"
column="iStudentId"
type="java.lang.Integer"
length="4"
>
<meta attribute="field-description">
@hibernate.property
column="iStudentId"
length="4"
</meta>
</key-property>
<key-property
name="courseId"
type="int"
column="iCourseId"

length="1" >
<meta attribute="field-description">
@hibernate.property
column="iCourseId"
length="1"

</meta>
</key-property>
</composite-id>

<property
name="gradeId"
type="int"
column="iGradeId"
not-null="true"
length="1"
>
<meta attribute="field-description">
@hibernate.property
column="iGradeId"
length="1"
not-null="true"
</meta>
</property>
<property
name="classid"
type="int"
column="iClassid"
not-null="true"
length="4"
>
<meta attribute="field-description">
@hibernate.property
column="iClassid"
length="4"
not-null="true"
</meta>
</property>

[lxf9501]

如何写many-to-one等等的关联呢？？