Question

我是Hibernate的新手。我有两个班级“quotation”和“quotation_item” 他们的数据库结构是这样的

create table quotation
(
        quotation_id  int primary key auto_increment,
        code varchar(20),
        client_name varchar(20)
);
create table quotation_item
(
    id int primary key auto_increment,
    quotation_id int,
    item_name varchar(20),
    rate int,
    qty int,
FOREIGN KEY (quotation_id) REFERENCES quotation(quotation_id)
);

Quotation.hbm.xml是这样的，



    <hibernate-mapping>
    <class name="com.paramatrix.pojo.Quotation" table="quotation">
    <id name="quotationId" type="int" column="quotation_id">
    <generator class="native" />
    </id>
        <property name="code" column="code" type="string" />
        <property name="clientName" column="client_name" type="string" />
        <set name="quotationItem" table="quotation_item" fetch="select" cascade="all">
        <key>
                <column name="quotation_id" not-null="true" />
            </key>
            <one-to-many class="com.paramatrix.pojo.QuotationItem" />
        </set>
        </class>
</hibernate-mapping>


QuotationItem.hbm.xml is like this,

<hibernate-mapping>
    <class name="com.paramatrix.pojo.QuotationItem" table="quotation_item">

        <id name="id" type="int" column="id">
            <generator class="native" />
        </id>
        <many-to-one name="quotation" class="com.paramatrix.pojo.Quotation"  cascade="save-update">
            <column name="quotation_id"  not-null="true" />        
        </many-to-one>

        <property name="itemName" column="item_name" type="string" />
        <property name="rate" column="rate" type="int" />
        <property name="qty" column="qty" type="int" />
    </class>

</hibernate-mapping>

<hibernate-mapping> <class name="com.paramatrix.pojo.Quotation" table="quotation"> <id name="quotationId" type="int" column="quotation_id"> <generator class="native" /> </id> <property name="code" column="code" type="string" /> <property name="clientName" column="client_name" type="string" /> <set name="quotationItem" table="quotation_item" fetch="select" cascade="all"> <key> <column name="quotation_id" not-null="true" /> </key> <one-to-many class="com.paramatrix.pojo.QuotationItem" /> </set> </class> </hibernate-mapping>

POJO是 1 GT; Quotation.java

<hibernate-mapping>
    <class name="com.paramatrix.pojo.QuotationItem" table="quotation_item">

        <id name="id" type="int" column="id">
            <generator class="native" />
        </id>
        <many-to-one name="quotation" class="com.paramatrix.pojo.Quotation"  cascade="save-update">
            <column name="quotation_id"  not-null="true" />        
        </many-to-one>

        <property name="itemName" column="item_name" type="string" />
        <property name="rate" column="rate" type="int" />
        <property name="qty" column="qty" type="int" />
    </class>

</hibernate-mapping>

2 - ; QuotationItem.java

主要方法是

public class Quotation {
    int quotationId;
    String code;
    String clientName;
    Set<QuotationItem> quotationItem=new HashSet<QuotationItem>();
//getter& setter    
}

Answer 1

尝试quotationItem.setQuotation(quotation)

Hibernate：获取not-null属性引用null或transient值

1 个答案: