當使用休眠

Question

hql = "select rm.* from remoteunit rm inner join mo m on rm.MOID = m.ID left join  
orgmomapping o on rm.MOID = o.MOID join organization org on org.ID = o.ORGANIZATIONID 
where m.DOMAINID = :id"; 

query = session.createSQLQuery(hql); 

該查詢返回的對象列表使用

remoteUnitList = (ArrayList<RemoteUnitDetails>)query.list(); 

查詢時，但得到類轉換異常當我試圖得到一個對象

RemoteUnitDetails details = (RemoteUnitDetails)remoteUnitsList.get(i); 

蔭得到類轉換異常。

Iam使用MySQL數據庫。當在hibernate中使用條件時，Iam無法匹配orgmomapping和remoteunit表。因爲

orgmomapping -> id, organizationId, remoteUnitId 
remoteunit -> id 

此遠程單元ID可能會或可能不會在orgmomapping中。

請sugguest解決

感謝

UPDATE

RemoteUnitDetails.hbm.xml

<hibernate-mapping> 
<class name="---.RemoteUnitDetails" table="remoteunit" 
    lazy="false"> 
    <id name="id" column="ID"> 
     <generator class="increment" /> 
    </id> 
    <many-to-one name="remoteUnit" column="MOID" 
     class="---.RemoteUnit" not-null="true"></many-to-one> 
    <property name="address" column="ADDRESS" /> 
    <property name="postalCode" column="POSTALCODE" /> 
    <property name="city" column="CITY" /> 
    <property name="region" column="REGION" /> 
    <property name="visible" column="VISIBLE" /> 
    <property name="lowPowerMode" column="LOWPOWERMODE" /> 
    <property name="wakeUpInterval" column="WAKEUPINTERVAL" /> 
    <property name="awakeInterval" column="AWAKEINTERVAL" /> 
    <property name="resetAtNextInterval" column="RESETATNEXTINTERVAL" /> 
    <property name="logInterval" column="LOGINTERVAL" /> 
    <property name="sendIntervalLogData" column="SENDINTERVALLOGDATA" /> 
    <property name="sendIntervalAttr1" column="SENDINTERVALATTR1" /> 
    <property name="sendIntervalAttr2" column="SENDINTERVALATTR2" /> 

    </class> 
</hibernate-mapping> 

RemoteUnit.hbm.xml

<hibernate-mapping> 
<class name="---.RemoteUnit" table="mo" lazy="false"> 
    <id name="id" column="ID"> 
     <generator class="increment" /> 
    </id> 

    <property name="name" /> 
    <property name="aliasName" column="SCREENNAME" /> 
    <property name="description" column="DESCRIPTION" /> 
    <property name="isActive" column="ISLIVE" /> 

    <many-to-one name="domain" column="DOMAINID" 
     class="---.Domain" not-null="true" /> 
    <!-- Foreign key --> 
    <many-to-one name="moType" column="MOTYPEID" 
     class="---.MoType" not-null="true" /> 
</class> 
</hibernate-mapping> 

OrgMoMapping.hbm.xml

<hibernate-mapping> 
<class name="---.OrgRemoteUnitMapping" table="orgmomapping" 
    lazy="false"> 
    <id name="id" column="ID"> 
     <generator class="identity" /> 
    </id> 

    <many-to-one name="organization" column="ORGANIZATIONID" 
     class="---.Organization" not-null="true"></many-to-one> 
    <many-to-one name="remoteUnit" column="MOID" 
     class="---.RemoteUnit" not-null="true"></many-to-one> 
</class> 
</hibernate-mapping> 

Answer 1

我不建議你使用本地SQL爲了這個目的，你可以很容易地做到這一點使用標準的API。你可以做這樣的事情。它可能會幫助你。

ProjectionList projections = Projections.projectionList(); 
projections.add(Projections.property("column.columnName"), "columnName"); 

Criteria criteria = getCurrentSession().createCriteria(<<remoteunit>>.class, "remoteunit"); 
criteria.createAlias("remoteunit.<<remoteunit_to_mo_joinfield>>", "mo", JoinType.INNER_JOIN); 
criteria.createAlias("mo.<<mo_to_orgmomapping_join_field>>", "orgmomapping", JoinType.LEFT_OUTER_JOIN); 
criteria.setProjection(projections); 
criteria.setResultTransformer(Criteria.ALIAS_TO_ENTITY_MAP); 
List<Map<String,? extends Object>> list = criteria.list();