冬眠单向的一对多,我有点困惑

你好,伙计们,如果你觉得这个问题很愚蠢,很抱歉。 我有3个表:货币(ID名称)语言(ID名称描述)交易(ID金额语言ID货币ID)

因此,我希望插入到事务中,但要确保它不会插入未知的语言或货币(这意味着如果没有现有的父语言和货币,则不应插入到messagetemplate)

这是我的映射文件

<?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">
<hibernate-mapping package="com.myproject.model">
 <class name="Transaction" table="transaction">
  <id name="id">
    <generator class="native"/>
  </id>
  <property column="amount" name="amount" type="String"/>
  <many-to-one class="CurrencyImpl" column="currency" name="currency"/>
  <many-to-one class="LanguageImpl" column="language" name="language"/>
 </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">
<hibernate-mapping package="com.myproject.model">
  <class name="Currency" table="currency">
   <id name="id">
    <generator class="native"/>
   </id>
   <property column="currency_name" name="name" type="String"/>
  </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">
<hibernate-mapping package="com.myproject.model">
 <class name="Language" table="language">
  <id name="id">
    <generator class="native"/>
  </id>
  <property column="language_name" name="name" type="String"/>
  <property column="language_description" name="description" type="String"/>
 </class>
</hibernate-mapping>

在当前的映射中,情况似乎并非如此。如何实现这一点?谢谢你的阅读