Question

我有一个包含3列作为主键的表。代码和映射如下：

复合键的类

public class CIDResultCurrentState implements Serializable
{
    private static final long serialVersionUID = -4346801004559840730L;

    private String mID = "";
    private String sNo = "";
    private String date = "";
    // getters, setters, equals(), hashCode() omitted for brevity 
}

表的类

public class ResultCurrentState implements IBaseModel, Serializable
{
    private static final long serialVersionUID = 5707101766665188676L;

    private CIDResultCurrentState ID;
    private byte[] rData;
    private byte[] pData;
    // getters, setters, equals(), hashCode() omitted for brevity 
}

hibernate xml map

<hibernate-mapping>

<class name="org.irvas.amrregina.backend.model.ResultCurrentState" table="RESULT_CURRENT_STATE">

    <composite-id name="ID" class="org.irvas.amrregina.backend.model.CIDResultCurrentState">
        <key-property name="mID" column="M_ID" type="java.lang.String"/>
        <key-property name="sNo" column="S_NO" type="java.lang.String"/>
        <key-property name="date" column="S_DATE" type="java.lang.String"/>
    </composite-id>

    <property name="rData" column="R_DATA" not-null="false" type="binary"/>
    <property name="pData" column="P_DATA" not-null="false" type="binary"/>

</class>

</hibernate-mapping>

所有这一切都很好。现在，我需要编写DetachedCriteria查询以获取特定的ResultCurrentState对象/记录。我试过这样的东西，但它不起作用（我不知道是否将此复合ID视为嵌套属性）：

//...
DetachedCriteria criteria = DetachedCriteria.forClass(ResultCurrentState.class);
DetachedCriteria criteriaID = criteria.createCriteria("ID");
criteriaID.add(Restrictions.eq("mID", arg.getType().getMID()));
criteriaID.add(Restrictions.eq("sNo", arg.getSN()));
criteriaID.add(Restrictions.eq("date", date));
return (ResultCurrentState)DataAccessUtils.uniqueResult(getHibernateTemplate().findByCriteria(criteriaID));

如果有人可以帮我写出正确的标准，我真的很感激感谢。

Answer 1

对于使用复合主键的标准，这应该足够了：

DetachedCriteria criteria = DetachedCriteria.forClass(ResultCurrentState.class);
criteria.add(Restrictions.eq("ID.mID", arg.getType().getMID()));
criteria.add(Restrictions.eq("ID.sNo", arg.getSN()));
criteria.add(Restrictions.eq("ID.date", date));

请注意，ID用作前缀，因为您已在类ResultCurrentState中使用该名称在POJO中声明了复合键：

private CIDResultCurrentState ID;

至于查询执行，我认为它是这样的（我的不同 - 不一定更好）：

return (ResultCurrentState)DataAccessUtils.uniqueResult(getHibernateTemplate().findByCriteria(criteria));

使用我的看起来像这样：

List<ResultCurrentState> result = DataAccessUtils.find(criteria);

Answer 2

Criteria criteria = session.forClass(ResultCurrentState.class);
DetachedCriteria criteriaID = DetachedCriteria.forClass(CIDResultCurrentState.class);
criteriaID.add(Restrictions.eq("mID", arg.getType().getMID()));
criteriaID.add(Restrictions.eq("sNo", arg.getSN()));
criteriaID.add(Restrictions.eq("date", date));
criteria.add(Subqueries.propertyIn("ID", criteriaID));
return criteria.list();

复合PK字段的分离标准？

2 个答案: