RE: [JBoss-user] java.lang.ClassCastException: $Proxy339

[Sternagel Annegret (PN-SYS/DAS)]

The findBy... method should return a reference to the remote interface of
the entitybean (the ejbFindBy... the primarykey), on that remote interface
you can call a method to get the Collection.

interface MyEBHome extends javax.ejb.EJBHome
{
        public MyEB findByCompanyId(long companyId) throws ....;
}

class MyEBBean implements javax.ejb.EntityBean
{
        public long ejbFindByCompanyId(long companyId) throws ....
        {
                // check if primary key is in db and return it
                ...
        }
}

interface MyEB extends javax.ejb.EJBObject
{
        public Collection getCompanyStakeholders(long companyId) throws
....;
}


Annegret

> -----Original Message-----
> From: Nicolai P Guba [SMTP:[EMAIL PROTECTED]]
> Sent: Dienstag, 31. Juli 2001 12:23
> To:   [EMAIL PROTECTED]
> Subject:      [JBoss-user] java.lang.ClassCastException: $Proxy339
> 
> A small problem with BMP.  I need some methods to return large amounts
> of data.  I noticed that initializing a new entity bean for every single
> data item (there are more than 50,000 rows), is very time consuming and
> not really required in this scenario.  So I switched to BMP and defined
> the following finder method:
> 
>     public Collection ejbFindByCompanyId (long companyId)
>       throws FinderException, RemoteException
>     {
>       Connection connection      = null;
>       PreparedStatement prepStmt = null;
>       ResultSet result           = null;
>       ArrayList list             = new ArrayList();
> 
>       try {
>           connection = this.dataSource.getConnection();
>           prepStmt = connection.prepareStatement (companyIdQuery);
>           prepStmt.setLong (1, companyId);
>           
>           result = prepStmt.executeQuery();
> 
>           while (result.next()){              
>               loadStakeholderData (result);
>               if (this.id > 0) {
>                   StakeholderData data = new StakeholderData();
>                   data.id                  = this.id;
>                   data.companyId           = this.companyId;
>                   data.firstName           = this.firstName;
>                   data.lastName            = this.lastName;
>                   data.email               = this.email;
>                   data.createdBy           = this.createdBy;
>                   data.dateCreated         = this.dateCreated;
>                   data.mimeTypePreference  = this.mimeTypePreference;
>                   data.modifiedBy          = this.modifiedBy;
>                   data.neverContact        = this.neverContact;
>                   data.optInType           = this.optInType;
>                   data.optInVerification   = this.optInVerification;
>                   data.source              = this.source;
>                   data.validEmail          = this.validEmail;
>                   data.lastModified        = this.lastModified;
>                   
>                   list.add (data);
> 
>                   System.out.println ("ejbFindByCompanyId: Adding " +
>                                       data.email);
>               }
>               else {
>                   System.out.println ("Invalid Stakehodler.id" +
>                                       this.id);
>               }
>           }
>           return list;
>       }
>       catch (SQLException e){
>           throw new EJBException (e.getMessage());
>       }
>       finally {
>           JDBCHelper.close (connection, prepStmt, result);
>       }        
>     }
> 
> Note that StakeholderData is a class implementing Serializable.  Now,
> when I call this finder from a session bean like:
> 
>     public ArrayList getCompanyStakeholders (StakeholderData data)
>       throws RemoteException, FinderException, EntityDataException
>     {
>       this.verifyLongId ("StakeholderData", data.companyId);
>       
>       try {
>           Collection c = this.stakeholderHome.findByCompanyId 
>                                                       (data.companyId);
>           ArrayList list = new ArrayList (c);
>           int size = list.size();
> 
>           System.out.println ("list size = " + size);
>           for (int i = 0; i < size; i++ ){
>               StakeholderData o = (StakeholderData)list.get(i);
>               System.out.println (o.email);
>           }
>           return list;
>       }
>       catch (FinderException e){
>           throw new EJBException (e.getMessage());
>       }
>     }
> 
> I get the following:
> 
> [ClientController] list size = 20
> [ClientController] TRANSACTION ROLLBACK EXCEPTION:null; nested exception
> is: 
>       javax.ejb.EJBException
> [ClientController] java.lang.ClassCastException: $Proxy339
> [ClientController]    at
> com.frontwire.cams.session.clientcontroller.ClientControllerEJB.getCompany
> Stakeholders(ClientControllerEJB.java)
> [ClientController]    at java.lang.reflect.Method.invoke(Native Method)
> [ClientController]    at
> org.jboss.ejb.StatelessSessionContainer$ContainerInterceptor.invoke(Statel
> essSessionContainer.java:472)
> [ClientController]    at
> org.jboss.ejb.plugins.StatelessSessionInstanceInterceptor.invoke(Stateless
> SessionInstanceInterceptor.java:87)
> [ClientController]    at
> org.jboss.ejb.plugins.TxInterceptorCMT.invokeNext(TxInterceptorCMT.java:13
> 3)
> [ClientController]    at
> org.jboss.ejb.plugins.TxInterceptorCMT.runWithTransactions(TxInterceptorCM
> T.java:263)
> [ClientController]    at
> org.jboss.ejb.plugins.TxInterceptorCMT.invoke(TxInterceptorCMT.java:99)
> [ClientController]    at
> org.jboss.ejb.plugins.SecurityInterceptor.invoke(SecurityInterceptor.java:
> 190)
> [ClientController]    at
> org.jboss.ejb.plugins.LogInterceptor.invoke(LogInterceptor.java:195)
> 
> ... 8<
> 
> Hmmm,  I've tried this with the finder returning an ArrayList but had no
> luck either
> 
> What did I do wrong or didn't do?
> 
> --
>   Nicolai P Guba    http://www.gnu.org         http://www.frontwire.com
>                     mailto:[EMAIL PROTECTED]     mailto:[EMAIL PROTECTED]
>                     GSM: +44 (0)7909 960 751   DDI: +44 (0)20 7368 9708
> 
> _______________________________________________
> JBoss-user mailing list
> [EMAIL PROTECTED]
> http://lists.sourceforge.net/lists/listinfo/jboss-user

_______________________________________________
JBoss-user mailing list
[EMAIL PROTECTED]
http://lists.sourceforge.net/lists/listinfo/jboss-user