雪山飛鵠

Exception in thread "main" org.hibernate.PropertyAccessException: exception setting property value with CGLIB (set hibernate.cglib.use_reflection_optimizer=false for more info) setter of com.dl.bean.Employee.setDepartment

    at org.hibernate.tuple.PojoEntityTuplizer.setPropertyValuesWithOptimizer(PojoEntityTuplizer.java:215)

    at org.hibernate.tuple.PojoEntityTuplizer.setPropertyValues(PojoEntityTuplizer.java:185)

    at org.hibernate.persister.entity.AbstractEntityPersister.setPropertyValues(AbstractEntityPersister.java:3232)

    at org.hibernate.engine.TwoPhaseLoad.initializeEntity(TwoPhaseLoad.java:129)

    at org.hibernate.loader.Loader.initializeEntitiesAndCollections(Loader.java:842)

    at org.hibernate.loader.Loader.doQuery(Loader.java:717)

    at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:224)

    at org.hibernate.loader.Loader.doList(Loader.java:2145)

    at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2029)

    at org.hibernate.loader.Loader.list(Loader.java:2024)

    at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:375)

    at org.hibernate.hql.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:308)

    at org.hibernate.engine.query.HQLQueryPlan.performList(HQLQueryPlan.java:153)

    at org.hibernate.impl.SessionImpl.list(SessionImpl.java:1106)

    at org.hibernate.impl.QueryImpl.list(QueryImpl.java:79)

    at com.dl.test.EmployeeTest.main(EmployeeTest.java:26)

Caused by: net.sf.cglib.beans.BulkBeanException: com.dl.bean.Employee cannot be cast to com.dl.bean.Department

    at com.dl.bean.Employee$$BulkBeanByCGLIB$$a415f505.setPropertyValues(<generated>)

    at org.hibernate.tuple.PojoEntityTuplizer.setPropertyValuesWithOptimizer(PojoEntityTuplizer.java:212)

    ... 15 more

Caused by: java.lang.ClassCastException: com.dl.bean.Employee cannot be cast to com.dl.bean.Department

    ... 17 more

查詢結果中包含null的值，對于一些數字或boolean包含null，定義該項時必須使用wrapper類型，而不能是primitive類型，例如使用Integer而不能是int,Boolean而不能是boolean否則會拋出exception

結論是：對于屬性在set/get時,屬性值為null而出現該異常

publicclass Employee {

    private Integer id;

    private String empname;

    private Integer empage;

    private String context;

    private Integer deptid;

    private Department department=new Department();

     //省略set()、get()方法

}

<hibernate-mapping package="com.dl.bean">

    <class name="Employee" table="employee">

         <id name="id" >

             <generator class="native"/>

         </id>

         <property name="empname"/>

         <property name="empage"/>

         <property name="context" />

         <property name="deptid" insert="false" update="false"/>

         <many-to-one name="department" column="deptid" cascade="all" class="Employee" /> //此處為錯誤的根源，這個錯誤很隱蔽，不仔細檢查很難發現

    </class>

    </hibernate-mapping>