带有额外列的多对多休眠映射？答案

【问题标题】：Many to many hibernate mapping with extra columns?带有额外列的多对多休眠映射？
【发布时间】：2012-05-12 01:49:09
【问题描述】：

您好，我在连接表中有多对多的映射和额外的列。表结构如下所示。

table vendor{vendor_id, vendor_name, vendor_password, etc...}
table student{student_id, student_name, student_password, etc..}
table test{test_id, test_subject, test_price,test_level, etc..}

关系如下

vendor to test --> many-to-many
student to test --> many-to-many

链接

table vendor_student_test{vendor_id, student_id, test_id, purchasedDate, assignedDate, writtenDate, result}

我按如下方式创建了 POJO 类

Vendor.java

public class Vendor {
Long vendorId;
Set<VendorStudentTest> tests;
//set and get
}

Student.java

public class Student{
Long studentId;
Set<VendorStudentTest> tests;
//set and get
}

Test.java

public class Test{
Long test_id;
double test_price;
//set and get and remaining fields
}

VendorStudentTest.java

public class VendorStudentTest{
public VendorStudentTestPK vendorStudentTestPK;
Date purchasedDate;
Date assignDate;
Date writtenDate;
double result;
//set and get accordingly
}

VendorStudentTestPK.java

public class VendorStudentTestPK{
Long vendor_id;
Long student_id;
Long test_id;
}

Hibernate 映射文件如下

vendor.hbm.xml

<set name="tests" table="vendor_student_test"
                inverse="true" lazy="true" fetch="select">
            <key>
                <column name="vendor_id" not-null="true" />
            </key>
            <one-to-many class="VendorStudentTest" />
        </set>

vendor_student_test.hbm.xml

    <composite-id name="vendorStudentTestPK"
        class="com.onlineexam.model.VendorStudentTestPK">

        <key-property name="vendor" column="vendor_id"
            type="java.lang.Long" />
        <key-property name="student" column="student_id"
            type="java.lang.Long" />
        <key-property name="test" column="test_id" type="java.lang.Long" />

    </composite-id>

学生.hbm.xml

<set name="tests" table="vendor_student_test"
                inverse="true" lazy="true" fetch="select">
            <key>
                <column name="student_id" not-null="true" />
            </key>
            <one-to-many class="VendorStudentTest" />
        </set>

test.hbm.xml

//this is mapped to other table

我是 hibernate 新手，这是正确的映射吗？

【问题讨论】：

标签： hibernate hibernate-mapping

【解决方案1】：

可以在这里找到带有注释案例的解决方案

How Do I Create Many to Many Hibernate Mapping for Additional Property from the Join Table?

使用 xml 文件的解决方案可以在这里找到： Mapping same class relation

这里：

Mapping same class relation - continuation

【讨论】：

所以，请参考最后两个链接。它解释了您需要知道的一切。
嗨，我已经更新了映射，你能告诉我是不是正确的。