Hibernate单向一对多。我有点困惑

Question

大家好，如果这个问题在你们看来很愚蠢，我很抱歉。我有3个表currency (id| name) language (id | name | description) transaction (id|amount|languageId | currencyid)

所以我想插入到事务中，但要确保它没有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，它就不应该插入到messagetemplate中)

以下是我的映射文件

<?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>

在目前的映射中，似乎不是case.how可以做到这一点？感谢您的阅读

Answer 1

您可以对CurrencyImpl和LanguageImpl进行多对一的引用，但这些类并没有映射，只有(可能对应的)接口被映射。我建议您从创建和映射具体的类开始，并在尝试与映射接口打乱之前使其正常工作。