class cast exception occurs while type casting the list object which is return from the hibernate to the entity class type.


Hibernate version: 3.1

Mapping documents:

accountgroup.hbm.xml

<?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">
<!--
Mapping file autogenerated by MyEclipse - Hibernate Tools
-->
<hibernate-mapping>
<class name="com.DAO.account.Accountgroup" table="accountgroup" catalog="pao">
<id name="accgrpid" type="java.lang.String">
<column name="ACCGRPID" length="4" />
<generator class="native" />
</id>
<property name="accgrpdesc" type="java.lang.String">
<column name="ACCGRPDESC" length="30" />
</property>
<property name="standard" type="java.lang.Short">
<column name="STANDARD" />
</property>
</class>
</hibernate-mapping>


Code between sessionFactory.openSession() and session.close():

public Account find(String query ,HttpServletRequest request)

{
Session session;
Account result;

ServletContext context=request.getSession().getServletContext();
SessionFactory _factory = (SessionFactory) context.getAttribute("SESSION_FACTORY_KEY_CRM");
session=_factory.openSession();

result = (Account) (session.createSQLQuery(query)).list(); // class cast exception occurs here

return result;



}





Full stack trace of any exception that occurs:

type Exception report

message

description The server encountered an internal error () that prevented it from fulfilling this request.

exception

javax.servlet.ServletException: [Ljava.lang.Object;
org.apache.struts.action.RequestProcessor.processException(RequestProcessor.java:545)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:486)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:274)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1482)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:525)
javax.servlet.http.HttpServlet.service(HttpServlet.java:763)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)


root cause

java.lang.ClassCastException: [Ljava.lang.Object;
com.BO.account.AccountActionBo.loadGroup(AccountActionBo.java:29)
com.action.account.AccountAction.loadGroup(AccountAction.java:54)
com.action.account.AccountAction.handleAction(AccountAction.java:42)
com.common.ChallengeAction.execute(ChallengeAction.java:39)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:484)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:274)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1482)
org.apache.struts.action.ActionServlet.doPost(ActionServlet.java:525)
javax.servlet.http.HttpServlet.service(HttpServlet.java:763)
javax.servlet.http.HttpServlet.service(HttpServlet.java:856)


note The full stack trace of the root cause is available in the Tomcat logs.



Name and version of the database you are using: mysql 5

Hi

What is the query that you passed.


Amila

This is the query i have passed to the hibernate

Pls help me .


"select accgrpid,accgrpdesc from account"

Hi



query = "select * from accountgroup"

SQLQuery query=session.createSQLQuery(query).addEntity(Account.class);
List list=query.list();
if(list.size()>0)
account=(Account) list.get(0);

You are trying to cast a List object to Account type . that is cause to ClassCastException


Amila

(Don't forget to rate)

i am getting the sql grammer exception now

org.hibernate.exception.SQLGrammarException: could not execute query
org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:67)
org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:43)
org.hibernate.loader.Loader.doList(Loader.java:2148)
org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2029)
org.hibernate.loader.Loader.list(Loader.java:2024)
org.hibernate.loader.custom.CustomLoader.list(CustomLoader.java:111)
org.hibernate.impl.SessionImpl.listCustomQuery(SessionImpl.java:1655)
org.hibernate.impl.AbstractSessionImpl.list(AbstractSessionImpl.java:142)
org.hibernate.impl.SQLQueryImpl.list(SQLQueryImpl.java:164)
com.DAO.ChallengeDAO.find(ChallengeDAO.java:34)
com.DAO.account.Accountgroup.loadGroup(Accountgroup.java:45)

Hi


You must select * fields from table. otherwise you should mention it as null

like this

"select accgrpid,accgrpdesc, null as standardfrom accountgroup"

Amila

(Don't forget to rate if helps)

still i am having this exception
i dont know y
then tell me where i need to add credit for u

org.hibernate.PropertyAccessException: exception setting property value with CGLIB (set hibernate.cglib.use_reflection_optimizer=false for more info) setter of com.DAO.account.Accountgroup.setStandard
org.hibernate.tuple.PojoEntityTuplizer.setPropertyValuesWithOptimizer(PojoEntityTuplizer.java:215)
org.hibernate.tuple.PojoEntityTuplizer.setPropertyValues(PojoEntityTuplizer.java:185)
org.hibernate.persister.entity.AbstractEntityPersister.setPropertyValues(AbstractEntityPersister.java:3232)
org.hibernate.engine.TwoPhaseLoad.initializeEntity(TwoPhaseLoad.java:129)
org.hibernate.loader.Loader.initializeEntitiesAndCollections(Loader.java:842)
org.hibernate.loader.Loader.doQuery(Loader.java:717)
org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:224)
org.hibernate.loader.Loader.doList(Loader.java:2145)
org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2029)
org.hibernate.loader.Loader.list(Loader.java:2024)
org.hibernate.loader.custom.CustomLoader.list(CustomLoader.java:111)

Hi

Can tou send code of setStandard() method

Amila

i am getting the same error

<?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">
<!--
Mapping file autogenerated by MyEclipse - Hibernate Tools
-->
<hibernate-mapping>
<class name="com.DAO.account.Accountgroup" table="accountgroup" catalog="pao">
<id name="accgrpid" type="java.lang.Integer">
<column name="accgrpid" />
</id>
<property name="accgrpdesc" type="java.lang.String">
<column name="accgrpdesc" length="30" not-null="true" />
</property>
<property name="standard" type="java.lang.String">
<column name="standard" length="30" not-null="true" />
</property>
</class>
</hibernate-mapping>


public String getAccgrpid() {
return accgrpid;
}

public void setAccgrpid(String accgrpid) {
this.accgrpid = accgrpid;
}

public String getAccgrpdesc() {
return accgrpdesc;
}

public void setAccgrpdesc(String accgrpdesc) {
this.accgrpdesc = accgrpdesc;
}

public String getStandard() {
return standard;
}

public void setStandard(String standard) {
this.standard = standard;
}

thank you amaila finally i have solved all the error

thank you very much amaila

Hi

error is:
<property name="standard" type="java.lang.String">
<column name="standard" length="30" not-null="true" />
</property>

when we select null as standard . hibernate try to set null into statdard property. but it is not allowed. so you can do two things.

1. change not-null="false"
2. change query to "select * from accountgroup"

Amila
(Don't forget to rate)

amila will u pls explain me whats happening while specifying

(session.createSQLQuery(query).addEntity(Accountgroup.class)).list();

addEntity of the particular class name whats happening there

is there any other possibility available without specifying that addEntity.

directly type casting the object.

pls help me

Hi

when using session.createSQLQuery(query) it will return a java.lang.Object array. we can't cast it to our mapped object. using addEntity() hibernate will fill a mapped object with appropriate value. so we can use that mapped object other than using a java.lang.Object array.


Amila

suppose if i am using

(session.createQuery(query)).list

then what should be done

now also i am getting the class cast exception is there any thing available to solve.

if i use createquery only it will be helpful for me because it automatically generates the hql.

Hi

Query query=session.createQuery(query);
List list=query.list();
if(list.size()>0)
account=(Account) list.get(0);