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Bookmark "NullPointerException" Watch "NullPointerException" New topic


krishna prasad gunasekaran
Ranch Hand

Joined: Jul 25, 2006
Posts: 158
when i call a remote method on ejb, it throws a NullPointerException.
i am passing a VO as an argument.

in Action

somewhere in my Action code...
ArrayList al = (ArrayList);

in Remote Interface
public collection throws RemoteException;

in Session Bean
public collection{

Error code :
java.rmi.ServerException: RemoteException occurred in server thread; nested exception is:
java.rmi.ServerException: RuntimeException; nested exception is:

I have checked the code in DAO, there is no way it is going to throw NullPointerException. what could be the reason for NullPointerException?

have a great day,
krishna prasad
Dilip Viswanath

Joined: Aug 03, 2007
Posts: 1
is your VO serializable?
Jeanne Boyarsky
internet detective

Joined: May 26, 2003
Posts: 30136

Let's start by trying to narrow down the problem. Does it work if you comment out the call to the DAO? If not, we can rule out the DAO. Does it work if you pass null as the VO? If not, the problem is in the VO.

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krishna prasad gunasekaran
Ranch Hand

Joined: Jul 25, 2006
Posts: 158
Jeanne, i did not comment out the call to DAO, instead i used the codes in DAO in my Action. It worked perfectly. when i passed null, instead of VO, no exception was thrown out. the code exection was back on track. so can we rule out the parts of DAO and VO.

what could be the reason
I agree. Here's the link:
subject: NullPointerException
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