Is it possible access local ejb in the web dynpro? Only remotly works.

[Former Member]

When I try create an EJB by the localHome it throws a ClassCastException.

Context jndi = new InitialContext();

MainSessionLocalHome beanLocalHome = (MainSessionLocalHome) jndi.lookup("localejbs/weg.net/atrapp/MainSessionBean");

MainSession session = (MainSession) beanLocalHome.create();

However if I invoke it remotely then It’s working perfectly.

Context jndi = new InitialContext();

Object obj = (Object) jndi.lookup("weg.net/atrapp/MainSessionBean");

MainSessionHome beanHome = (MainSessionHome) PortableRemoteObject.narrow(obj, MainSessionHome.class);

MainSession session = (MainSession) beanHome.create();

Follow the detailed information about the exception.

java.lang.ClassCastException

at net.weg.atr.wd.MainView.onActiononActiveLocal(MainView.java:171)

at net.weg.atr.wd.wdp.InternalMainView.wdInvokeEventHandler(InternalMainView.java:148)

at com.sap.tc.webdynpro.progmodel.generation.DelegatingView.invokeEventHandler(DelegatingView.java:87)

at com.sap.tc.webdynpro.progmodel.controller.Action.fire(Action.java:67)

at com.sap.tc.webdynpro.clientserver.window.WindowPhaseModel.doHandleActionEvent(WindowPhaseModel.java:420)

at com.sap.tc.webdynpro.clientserver.window.WindowPhaseModel.processRequest(WindowPhaseModel.java:132)

at com.sap.tc.webdynpro.clientserver.window.WebDynproWindow.processRequest(WebDynproWindow.java:335)

at com.sap.tc.webdynpro.clientserver.cal.AbstractClient.executeTasks(AbstractClient.java:143)

at com.sap.tc.webdynpro.clientserver.session.ApplicationSession.doProcessing(ApplicationSession.java:313)

at com.sap.tc.webdynpro.clientserver.session.ClientSession.doApplicationProcessingStandalone(ClientSession.java:759)

at com.sap.tc.webdynpro.clientserver.session.ClientSession.doApplicationProcessing(ClientSession.java:712)

at com.sap.tc.webdynpro.clientserver.session.ClientSession.doProcessing(ClientSession.java:261)

at com.sap.tc.webdynpro.clientserver.session.RequestManager.doProcessing(RequestManager.java:149)

at com.sap.tc.webdynpro.serverimpl.defaultimpl.DispatcherServlet.doContent(DispatcherServlet.java:62)

at com.sap.tc.webdynpro.serverimpl.defaultimpl.DispatcherServlet.doPost(DispatcherServlet.java:53)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:760)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)

at com.sap.engine.services.servlets_jsp.server.HttpHandlerImpl.runServlet(HttpHandlerImpl.java:401)

at com.sap.engine.services.servlets_jsp.server.HttpHandlerImpl.handleRequest(HttpHandlerImpl.java:266)

at com.sap.engine.services.httpserver.server.RequestAnalizer.startServlet(RequestAnalizer.java:387)

at com.sap.engine.services.httpserver.server.RequestAnalizer.startServlet(RequestAnalizer.java:365)

at com.sap.engine.services.httpserver.server.RequestAnalizer.invokeWebContainer(RequestAnalizer.java:944)

at com.sap.engine.services.httpserver.server.RequestAnalizer.handle(RequestAnalizer.java:266)

at com.sap.engine.services.httpserver.server.Client.handle(Client.java:95)

at com.sap.engine.services.httpserver.server.Processor.request(Processor.java:175)

at com.sap.engine.core.service630.context.cluster.session.ApplicationSessionMessageListener.process(ApplicationSessionMessageListener.java:33)

at com.sap.engine.core.cluster.impl6.session.MessageRunner.run(MessageRunner.java:41)

at com.sap.engine.core.thread.impl3.ActionObject.run(ActionObject.java:37)

at java.security.AccessController.doPrivileged(Native Method)

at com.sap.engine.core.thread.impl3.SingleThread.execute(SingleThread.java:100)

at com.sap.engine.core.thread.impl3.SingleThread.run(SingleThread.java:170)

[Former Member · Accepted solution]

Hi

Try this if you can see <b>MainSessionLocal</b> interface and declare all your methods in that

Context jndi = new InitialContext();

MainSessionLocalHome beanLocalHome = (MainSessionLocalHome) jndi.lookup("localejbs/weg.net/atrapp/MainSessionBean");

MainSessionLocal session = (MainSessionLocal) beanLocalHome.create();

Regards

Abhijith YS

[Former Member · Accepted solution]

Abhijith YS, I didn't undertand your post, your sugested code is exactly equals as I put before in my problem...

[Former Member]

Hello

maybe there is something wrong with the ejb-refs in the deployment descriptor, looks like the jndi lookup returns a wrong EJB Home Object

try this:

Context jndi = new InitialContext();
Object beanLocalHome = jndi.lookup("localejbs/weg.net/atrapp/MainSessionBean");
System.out.println (beanLocalHome.getClass().getName());

(or replace System.out by something you can have a look at)

Then you will see the type of Object returned by jndi lookup for further error research.

I think the object returned by the jndi lookup is a wrapper generated by the ejb container, maybe you need a call to getInterfaces() too, to see which Interfaces are implemented by the returned BeanHome Object. (hava a look <a href="http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Class.html#getInterfaces()">here</a> )

regards

franz

reward points if useful

[Former Member]

I checked it but I didn't identify any problem, except by the strange name of the implementation...

beanLocalHome.getClass().getName()

net.weg.atr.model.session.MainSessionLocalHomeImpl0_0

beanLocalHome.getClass().getInterfaces()

[0]

interface net.weg.atr.model.session.MainSessionLocalHome

[1]

interface com.sap.engine.services.ejb.exceptions.SessionExceptionConstants

[2]

interface com.sap.engine.interfaces.ejb.serialization.EJBSerializable

[Former Member]

Hello

try the solution from Abhijith YS (reply above, I think this is correct solution)

check line with MainSessionLocal - your code uses the class MainSession

Context jndi = new InitialContext();
MainSessionLocalHome beanLocalHome = (MainSessionLocalHome) jndi.lookup("localejbs/weg.net/atrapp/MainSessionBean");
MainSessionLocal session = (MainSessionLocal) beanLocalHome.create();

if this also doesn't work, check which class/interfaces are implemented by the Object returned from beanLocalHome.create.

And check your deployment descriptor, maybe there is something wrong with the declaration of the ejb interfaces

Regards

franz

Message was edited by:

Franz Ferner

[Former Member]

My code was using the tip of the Abhijith YS and the same problem are hapening.

The descriptor is with default values, build by the plugin... <home>net.weg.atr.model.session.MainSessionHome</home>

<remote>net.weg.atr.model.session.MainSession</remote>

<local-home>net.weg.atr.model.session.MainSessionLocalHome</local-home>

<local>net.weg.atr.model.session.MainSessionLocal</local>

<ejb-class>net.weg.atr.model.session.MainSessionBean</ejb-class>

[Former Member]

I think that I was with problems in my deploy tool. Now it's working.

[Former Member]

Hi,

Could you please share your solution with us on how to fix this problem? What's the problem with your deploy tool?

Thanks very much in advance.

Regards,

Van

[Former Member]

Hi,

It is possible! Have a look at the WebDynpro Java Tutorials, how to use EJBs in Web Dynpro Java (<a href="https://www.sdn.sap.comhttp://www.sdn.sap.comhttp://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/com.sap.km.cm.docs/library/uuid/1f5f3366-0401-0010-d6b0-e85a49e93a5c">Using EJBs in Web Dynpro Applications</a>).

Regards,

Daniel

[Former Member]

I've already seem this tutorial and others about using web dynpro with jsp and jndi... My application doesn't have a java project to implement the command design patterns, then the code that I put in the first post is from the web dynpro mainController.