ClassCastException, and we *are* using "-Djbo.server.in_oc4j=true "

Question

Hi,
We have several applications using the same BC4J objects running on the same AppSer (Oracle9iAS Containers for J2EE 9.0.2.0.0, running on Ibm AIX 4.3.3).
Each time we deploy a specific application, all OTHER applications get ClassCastExceptions, like
"java.lang.ClassCastException: <myPackage>.<myTable>ViewRowImpl"
We DO start OC4J with the -Djbo.server.in_oc4j=true option.
Any ideas?
Regards,
Jaime Conejo/ Martijn Hinten

Answer 1

Hi,
I already tried this, but the getClass() method reports exactly the class as I am expecting! To be more precise:
I am executing the following code:
ApplicationModule am;
ViewObject vo;
VCboLookupArtFeViewRow titelRow; // This is an interface, which is implemented by
// VCboLookupArtFeViewRowImpl
vo = am.findViewObject("VCboLookupArtFeView");
Sytem.out.println("rowtype:"+vo.first().getClass()); // (1)
titelRow = (VCboLookupArtFeViewRow) = vo.first(); // (2)
Now, at line (1) the console reports that the object type is is 'com.centraalboekhuis.cbonline.model.VCboLookupArtFeViewRowImpl'. Note this is the "impl" class that implements my VCboLookupArtFeViewRow-interface. I am not casting to the "impl" class, as the Bc4j manual tells me I should use the interface instead (which makes sense). So, I am casting to an interface reference type, which my class implements. Should work.
However at line (2) the following ClassCastException is thrown (see below). It tells me my object is not a VCboLookupArtFeViewRowImpl. But I now it is, as my debug statement tells me it is. Again, I am casting to an interface type, but VCboLookupArtFeViewRowImpl implements this interface type, so this should work. As a proof that it indeed works I can demonstrate that when I deploy my application all works fine, but when another project member deploys his application, my application fails with the ominous ClassCastException.
So, what is happening here?
java.lang.ClassCastException: com.centraalboekhuis.cbonline.model.VCboLookupArtFeViewRowImpl     at com.centraalboekhuis.cbonline.bestellen.ModelGetBestelTitelDetails.perform(ModelGetBestelTitelDetails.java:55)     at com.cumquatit.j2ee.controller.web.HttpController.doAction(HttpController.java:139)     at com.centraalboekhuis.cbonline.CBOnline.doAction(CBOnline.java:124)     at com.cumquatit.j2ee.controller.web.HttpController.doPost(HttpController.java:163)     at javax.servlet.http.HttpServlet.service(HttpServlet.java(Compiled Code))     at javax.servlet.http.HttpServlet.service(HttpServlet.java(Compiled Code))     at javax.servlet.http.HttpServlet.service(HttpServlet.java(Compiled Code))     at com.evermind[Oracle9iAS (2.0.0.0) Containers for J2EE].server.http.ServletRequestDispatcher.invoke(ServletRequestDispatcher.java(Compiled Code))     at com.evermind[Oracle9iAS (2.0.0.0) Containers for J2EE].server.http.ServletRequestDispatcher.forwardInternal(ServletRequestDispatcher.java(Compiled Code))     at com.evermind[Oracle9iAS (2.0.0.0) Containers for J2EE].server.http.HttpRequestHandler.processRequest(HttpRequestHandler.java(Compiled Code))     at com.evermind[Oracle9iAS (2.0.0.0) Containers for J2EE].server.http.HttpRequestHandler.run(HttpRequestHandler.java(Compiled Code))     at com.evermind[Oracle9iAS (2.0.0.0) Containers for J2EE].util.ThreadPoolThread.run(ThreadPoolThread.java(Compiled Code))
Thanks