RMI server object lookup in a session bean

Hi all,
I am getting MarshalException when I call java.rmi.Naming.lookup() in a session
bean. Following is the code and exception. Please note that I am using java.rmi
package instead of weblogic.rmi and that both the session bean and RMI server
object (a startup class) is deployed on the same machine.
Thanks for your help in advance.
// a simple, replica-aware session bean method
// some code here
try {
MediatorInterface mediator = (MediatorInterface) java.rmi.Naming.lookup("rmi://localhost:7001/TestMediator);
catch (Exception e) {
// log the exception
The exception:
java.rmi.MarshalException: Error marshaling transport header; nested exception
i
s:
java.io.EOFException
java.io.EOFException
at java.io.DataInputStream.readByte(DataInputStream.java:224)
at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:206
at sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:174)
at sun.rmi.server.UnicastRef.newCall(UnicastRef.java:318)
at sun.rmi.registry.RegistryImpl_Stub.lookup(Unknown Source)
at java.rmi.Naming.lookup(Naming.java:84)
at test.mgmtop.CreateNetworkOpHandler.execute(CreateNetworkOpHandler.jav
a:88)
at test.mgmtop.CreateNetworkOpHandler.perform(CreateNetworkOpHandler.jav
a:28)
at test.ejb.MgmtServiceBean.create(MgmtServiceBean.java:57)
at test.ejb.MgmtServiceSession_idi8yo_EOImpl.create(MgmtServiceSession_i
di8yo_EOImpl.java:46)
at test.ejb.MgmtServiceSession_idi8yo_EOImpl_WLSkel.invoke(Unknown Sourc
e)
at weblogic.rmi.internal.BasicServerRef.invoke(BasicServerRef.java:346)
at weblogic.rmi.cluster.ReplicaAwareServerRef.invoke(ReplicaAwareServerR
ef.java:114)
at weblogic.rmi.internal.BasicServerRef$1.run(BasicServerRef.java:300)
at weblogic.security.service.SecurityServiceManager.runAs(SecurityServic
eManager.java:762)
at weblogic.rmi.internal.BasicServerRef.handleRequest(BasicServerRef.jav
a:295)
at weblogic.rmi.internal.BasicExecuteRequest.execute(BasicExecuteRequest
.java:30)
at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:152)
at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:133)

Hi Pyung,
How about trying this instead:
InitialContext ctx = new InitialContext();
MediatorInterface mediator = (MediatorInterface) ctx.lookup("TestMediator");
This assumes your startup class binds the Mediator to the JNDI name "TestMediator".
- Matt
Pyung Yoon wrote:
Hi all,
I am getting MarshalException when I call java.rmi.Naming.lookup() in a session
bean. Following is the code and exception. Please note that I am using java.rmi
package instead of weblogic.rmi and that both the session bean and RMI server
object (a startup class) is deployed on the same machine.
Thanks for your help in advance.
// a simple, replica-aware session bean method
// some code here
try {
MediatorInterface mediator = (MediatorInterface) java.rmi.Naming.lookup("rmi://localhost:7001/TestMediator);
catch (Exception e) {
// log the exception
The exception:
java.rmi.MarshalException: Error marshaling transport header; nested exception
i
s:
java.io.EOFException
java.io.EOFException
at java.io.DataInputStream.readByte(DataInputStream.java:224)
at sun.rmi.transport.tcp.TCPChannel.createConnection(TCPChannel.java:206
at sun.rmi.transport.tcp.TCPChannel.newConnection(TCPChannel.java:174)
at sun.rmi.server.UnicastRef.newCall(UnicastRef.java:318)
at sun.rmi.registry.RegistryImpl_Stub.lookup(Unknown Source)
at java.rmi.Naming.lookup(Naming.java:84)
at test.mgmtop.CreateNetworkOpHandler.execute(CreateNetworkOpHandler.jav
a:88)
at test.mgmtop.CreateNetworkOpHandler.perform(CreateNetworkOpHandler.jav
a:28)
at test.ejb.MgmtServiceBean.create(MgmtServiceBean.java:57)
at test.ejb.MgmtServiceSession_idi8yo_EOImpl.create(MgmtServiceSession_i
di8yo_EOImpl.java:46)
at test.ejb.MgmtServiceSession_idi8yo_EOImpl_WLSkel.invoke(Unknown Sourc
e)
at weblogic.rmi.internal.BasicServerRef.invoke(BasicServerRef.java:346)
at weblogic.rmi.cluster.ReplicaAwareServerRef.invoke(ReplicaAwareServerR
ef.java:114)
at weblogic.rmi.internal.BasicServerRef$1.run(BasicServerRef.java:300)
at weblogic.security.service.SecurityServiceManager.runAs(SecurityServic
eManager.java:762)
at weblogic.rmi.internal.BasicServerRef.handleRequest(BasicServerRef.jav
a:295)
at weblogic.rmi.internal.BasicExecuteRequest.execute(BasicExecuteRequest
java:30)
at weblogic.kernel.ExecuteThread.execute(ExecuteThread.java:152)
at weblogic.kernel.ExecuteThread.run(ExecuteThread.java:133)

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"Pyung Yoon" <[email protected]> writes:
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at $Proxy0.add(Unknown Source) at ClientAccessLocalCalculator.main(ClientAccessLocalCalculator.java:14)
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| +- remote (proxy: $Proxy83 implements interface bean.CalculatorRemote,interface org.jboss.ejb3.JBossProxy,interface javax.ejb.EJBObject)
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C:\>asadmin
Use "exit" to exit and "help" for online help.
asadmin> list-jndi-entries
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bean.CalculatorRemote: javax.naming.Reference
jbi: com.sun.enterprise.naming.TransientContext
jdbc: com.sun.enterprise.naming.TransientContext
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bean.CalculatorRemote__3_x_Internal_RemoteBusinessHome__: javax.naming.Reference
bean.CalculatorRemote#bean.CalculatorRemote: javax.naming.Reference
ejb: com.sun.enterprise.naming.TransientContext
Command list-jndi-entries executed successfully.
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Help is greatly appreciated!
Vincent.

I've just found the solution from Steve Muench weblog, always useful by the way!
You can find the solution at this link http://radio.weblogs.com/0118231/stories/2004/05/07/handcodingDynamicDiscoveryOfEjbdeployedAppmodule.html
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Dr. Laurence Leff, Associate Professor of Computer Science WIU ST447 61455
Pager 309 367 0787, Fax 309 298 2302

My apology for posting this message twice. I looked for it before and
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Also, I did resolve one problem. System.out.println does go to
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Initial error on Sun Solaris:
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr: Exception in thread "service-j2ee-25" org.omg.CORBA.OBJ_ADAPTER: vmcid: SUN minor code: 1015 completed: No
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.ee.internal.POA.GenericPOAServerSC.preinvoke(GenericPOAServerSC.java:389)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.ee.internal.POA.ServantCachePOAClientSC.initServant(ServantCachePOAClientSC.java:112)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.ee.internal.POA.ServantCachePOAClientSC.setOrb(ServantCachePOAClientSC.java:95)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.ee.internal.iiop.CDRInputStream_1_0.createDelegate(CDRInputStream_1_0.java:760)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.ee.internal.iiop.CDRInputStream_1_0.internalIORToObject(CDRInputStream_1_0.java:750)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.ee.internal.iiop.CDRInputStream_1_0.read_Object(CDRInputStream_1_0.java:669)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.ee.internal.iiop.CDRInputStream_1_0.read_abstract_interface(CDRInputStream_1_0.java:890)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.ee.internal.iiop.CDRInputStream_1_0.read_abstract_interface(CDRInputStream_1_0.java:884)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.ee.internal.iiop.CDRInputStream.read_abstract_interface(CDRInputStream.java:307)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.se.internal.io.IIOPInputStream.readObjectDelegate(IIOPInputStream.java:228)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.se.internal.io.IIOPInputStream.readObjectOverride(IIOPInputStream.java:381)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at java.io.ObjectInputStream.readObject(ObjectInputStream.java:318)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.enterprise.iiop.IIOPHandleDelegate.getStub(IIOPHandleDelegate.java:58)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.enterprise.iiop.IIOPHandleDelegate.readEJBObject(IIOPHandleDelegate.java:38)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.ejb.portable.HandleImpl.readObject(HandleImpl.java:91)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.se.internal.io.IIOPInputStream.readObject(Native Method)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.se.internal.io.IIOPInputStream.invokeObjectReader(IIOPInputStream.java:1298)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.se.internal.io.IIOPInputStream.inputObject(IIOPInputStream.java:908)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.se.internal.io.IIOPInputStream.simpleReadObject(IIOPInputStream.java:261)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.se.internal.io.ValueHandlerImpl.readValueInternal(ValueHandlerImpl.java:247)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.se.internal.io.ValueHandlerImpl.readValue(ValueHandlerImpl.java:209)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.ee.internal.iiop.CDRInputStream_1_0.read_value(CDRInputStream_1_0.java:981)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.ee.internal.iiop.CDRInputStream.read_value(CDRInputStream.java:287)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.sun.corba.ee.internal.javax.rmi.CORBA.Util.copyObject(Util.java:598)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at javax.rmi.CORBA.Util.copyObject(Util.java:314)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.telstra.nodeman.ejb._NodeMaint_Stub.getHandle(Unknown Source)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.telstra.nodeman.arch.NMAViewBeanProxy.checkBeans(NMAViewBeanProxy.java:631)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.telstra.nodeman.view.html.NMAStandardButton.handleRequest(NMAStandardButton.java:143)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.telstra.nodeman.arch.NMAViewBeanBase.handleRequest(NMAViewBeanBase.java:1573)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.iplanet.jato.view.ViewBeanBase.dispatchInvocation(ViewBeanBase.java:824)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.iplanet.jato.view.ViewBeanBase.invokeRequestHandlerInternal(ViewBeanBase.java:637)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.iplanet.jato.view.ViewBeanBase.invokeRequestHandler(ViewBeanBase.java:595)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.iplanet.jato.ApplicationServletBase.dispatchRequest(ApplicationServletBase.java:772)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.iplanet.jato.ApplicationServletBase.processRequest(ApplicationServletBase.java:446)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.iplanet.jato.ApplicationServletBase.doPost(ApplicationServletBase.java:324)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.telstra.nodeman.view.ViewServlet.doPost(ViewServlet.java:243)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at javax.servlet.http.HttpServlet.service(HttpServlet.java:760)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at org.apache.catalina.core.StandardWrapperValve.invokeServletService(StandardWrapperValve.java:720)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at org.apache.catalina.core.StandardWrapperValve.access$000(StandardWrapperValve.java:118)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at org.apache.catalina.core.StandardWrapperValve$1.run(StandardWrapperValve.java:278)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at java.security.AccessController.doPrivileged(Native Method)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:274)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:505)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:212)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:505)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:203)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:505)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.iplanet.ias.web.connector.nsapi.NSAPIProcessor.process(NSAPIProcessor.java:158)
[10/Aug/2004:08:04:57] WARNING (17227): CORE3283: stderr:      at com.iplanet.ias.web.WebContainer.service(WebContainer.java:598)
The above error caused the server to use all available memory and required a reboot to proceed.
Subsequent testing against the Sun Appliucation Server 7 on Windows 2000 dev environment using the Sun Studio IDE for debugging and trace statements inserted in the code indicate that the Application Server is removing the Stateful Session Beans when they time out without an ejbPassivate event and without serializing the beans to the data-store. cache-idle-timeout-in-seconds set to 180 and removal-timeout-in-seconds set to 1800.
The server.log indicates that the beans are timing out:
[19/Aug/2004:18:15:10] WARNING ( 1664): [NRU-com.telstra.nodeman.ejb.AddressMaintBean]: IdleBeanCleanerTask finished after removing 2 idle beans
Trace statements inserted in ejbPassivate do not appear in the log.
It is my understanding that the above timeout should have caused an ejbPasssivate and serialization of the beans.
The beans have been validated using Sun Java Studio Enterprise 6 with 'EJB validate'.
My reading of the problem is that the beans are not being serialized and the error occurs when the application attempts to reference (getHandle) the bean after timeout.
Any suggestions would be appreciated.

Thanks Thorick.
I am using NRU caching. WL 7.0 SP2.
I have not defined idle-timeout-seconds in my weblogic-ejb-jar.xml. As I understand
the default value for this is 600secs. So the ejbs should be removed after this
time. Below is the
weblogic-ejb-jar.xml that I am using.
<!DOCTYPE weblogic-ejb-jar PUBLIC '-//BEA Systems, Inc.//DTD WebLogic 7.0.0 EJB//EN'
'http://www.bea.com/servers/wls700/dtd/weblogic-ejb-jar.dtd'>

<weblogic-ejb-jar>
<weblogic-enterprise-bean>
<ejb-name>Cart</ejb-name>
<stateful-session-descriptor>
<stateful-session-clustering>
<home-is-clusterable>true</home-is-clusterable>
<replication-type>InMemory</replication-type>
</stateful-session-clustering>
</stateful-session-descriptor>
<transaction-descriptor>
     <trans-timeout-seconds>
          60
     </trans-timeout-seconds>
</transaction-descriptor>
<jndi-name>CartHome</jndi-name>
</weblogic-enterprise-bean>
</weblogic-ejb-jar>
"thorick" <[email protected]> wrote:
>
The idle-timeout-seconds property controls the timeout/removal behavior.
which stateful session cache type are you using ? LRUCache or NRUCache

Transaction is not Rolling Back in Stateless Session Bean

          Hi,
          I am using UserTransaction in Stateless Session bean .
          Transaction is not rolling back.
          The following code is writen in stateless session bean. In UserTransaction i am
          calling Two methods of another stateless session bean.
          The problem is if doJob2() method fails, doJob1() method is rolling back. These
          two methods consist of SQL statement with different Connection Object from TXDataSource.And
          session bean(TestSession) is set to CMT, attribute as "Required".
          try{
          Context ictx=new InitialContext();
          TestHome home=(TestHome)ictx.lookup("TestSession");
               utx = sessionCtx.getUserTransaction();
               utx.begin();
          TestRemote remote=home.create();
               remote.doJob1();
               remote.doJob2();
               utx.commit();
          }catch(Exception e)
               try{
               utx.rollback();
          }catch(Exception ex)
               System.out.println("unable to rollback"+ex);
          if any SQL Exception as occured in doJob2(), its calling method utx.rollback()
          in catch block. but SQL statements executed thru. doJob1() are not rolling back.
          what might be the reason?
          thanks
          Ranganath


          Thanx Priscilla ,
          Transaction is working.
          ranganath
          "Priscilla Fung" <[email protected]> wrote:
          >
          >In your ejb-jar.xml, you should specify <transaction-type> element to
          >be "Container"
          >for container-managed transaction. If you specified it to be "Bean" for
          >bean-managed
          >transaction, EJB ontainer will suspend the caller's transaction before
          >starting
          >a new transaction for your doJobX() methods. Thus, doJob1()nd doJob2()
          >will be
          >executing in different transactions, and thus rolling back doJob2()'s
          >transaction
          >will have no effect on work done and committed in doJob1()'s transaction.
          >
          >Regards,
          >
          >Priscilla
          >
          >
          >"Ranganath" <[email protected]> wrote:
          >>
          >>
          >>
          >>I am sending config.xml,deployment descriptors, code snippet for TestSession.
          >>i
          >>am using weblogic6.0sp2.
          >>if you need any aditional info. please let me know.
          >>
          >>thanks
          >>ranganath
          >>
          >>EJB-JAR.xml
          >>
          >><?xml version="1.0"?>
          >>
          >><!DOCTYPE ejb-jar PUBLIC '-//Sun Microsystems, Inc.//DTD Enterprise
          >JavaBeans
          >>1.1//EN' 'http://java.sun.com/j2ee/dtds/ejb-jar_1_1.dtd'>
          >>
          >><ejb-jar>
          >>     <enterprise-beans>
          >>     <session>
          >>          <ejb-name>TestSession</ejb-name>
          >>          <home>com.apar.sslbridge.test.TestHome</home>
          >>          <remote>com.apar.sslbridge.test.TestRemote</remote>
          >>          <ejb-class>com.apar.sslbridge.test.TestBean</ejb-class>
          >>          <session-type>Stateless</session-type>
          >>          <transaction-type>Bean</transaction-type>
          >>          <resource-ref>
          >>     <res-ref-name>jdbc/oraclePool</res-ref-name>
          >>     <res-type>javax.sql.DataSource</res-type>
          >>     <res-auth>Container</res-auth>
          >>          </resource-ref>
          >>     </session>
          >>     </enterprise-beans>
          >>     <assembly-descriptor>
          >>     <container-transaction>
          >>          <method>
          >>          <ejb-name>TestSession</ejb-name>
          >>          <method-intf>Remote</method-intf>
          >>          <method-name>*</method-name>
          >>          </method>
          >>          <trans-attribute>Required</trans-attribute>
          >>     </container-transaction>
          >> </assembly-descriptor>
          >></ejb-jar>
          >>
          >>
          >>TestSession CODE:
          >>
          >>
          >>     public void doJob1() throws RemoteException
          >>     {
          >>     Statement st = null;
          >>     String query=null;
          >>     try{
          >>     con=getConnection();
          >>     st=con.createStatement();
          >>     query="insert into x values("+x+++")";
          >>     System.out.println(query);
          >>     int rec=st.executeUpdate(query);
          >>     }catch(SQLException sqle)
          >>     {
          >>     System.out.println("SQL Exception "+sqle);
          >> throw new RemoteException("RemoteException*****SQLError");
          >>     } catch (Exception e) {
          >>     System.out.println("Exception "+e);
          >> throw new RemoteException("RemoteException*****GenralError");
          >> }
          >>}
          >>
          >>
          >> public void doJob2()throws RemoteException
          >> {
          >> Connection con=null;
          >> Statement st = null;
          >> String query=null;
          >> try{
          >> con=getConnection();
          >> st=con.createStatement();
          >> query="insert into y values("+x+++")";
          >> System.out.println(query);
          >> int rec=st.executeUpdate(query);
          >> }catch(SQLException sqle)
          >> {
          >> System.out.println("SQL Exception "+sqle);
          >> throw new RemoteException("RemoteException*****SQLError");
          >> } catch (Exception e) {
          >> System.out.println("Exception "+e);
          >> throw new RemoteException("RemoteException*****GenralError");
          >>}
          >>}
          >>private Connection getConnection(){
          >>try {
          >>Connection con = StaticParams.POOL_DATASOURCE.getConnection();
          >>return con;
          >>     } catch(Exception e) {
          >>     System.out.println("TestBean.getConnection() Unable to get get pool
          >>connection
          >>" + e);
          >>     }
          >>}
          >>
          >>
          >>
          >>
          >>"Priscilla Fung" <[email protected]> wrote:
          >>>
          >>>It should work if you are using TxDataSource. Could you post your
          >config.xml,
          >>>deployment descriptors, code snippet for TestSession?
          >>>
          >>>Regards,
          >>>
          >>>Priscilla
          >>>
          >>>"Ranganath" <[email protected]> wrote:
          >>>>
          >>>>Hi,
          >>>>
          >>>> I am using UserTransaction in Stateless Session bean .
          >>>> Transaction is not rolling back.
          >>>>
          >>>>The following code is writen in stateless session bean. In UserTransaction
          >>>>i am
          >>>>calling Two methods of another stateless session bean.
          >>>> The problem is if doJob2() method fails, doJob1() method is rolling
          >>>> back. These
          >>>>two methods consist of SQL statement with different Connection Object
          >>>>from TXDataSource.And
          >>>>session bean(TestSession) is set to CMT, attribute as "Required".
          >>>>
          >>>> try{
          >>>> Context ictx=new InitialContext();
          >>>> TestHome home=(TestHome)ictx.lookup("TestSession");
          >>>>     utx = sessionCtx.getUserTransaction();
          >>>>     utx.begin();
          >>>> TestRemote remote=home.create();
          >>>>     remote.doJob1();
          >>>>     remote.doJob2();
          >>>>     utx.commit();
          >>>> }catch(Exception e)
          >>>> {
          >>>>     try{
          >>>>      utx.rollback();
          >>>> }catch(Exception ex)
          >>>> {
          >>>>     System.out.println("unable to rollback"+ex);
          >>>>     }
          >>>> }
          >>>>if any SQL Exception as occured in doJob2(), its calling method utx.rollback()
          >>>>in catch block. but SQL statements executed thru. doJob1() are not
          >>rolling
          >>>>back.
          >>>>what might be the reason?
          >>>>
          >>>>thanks
          >>>>Ranganath
          >>>
          >>
          >

How to download a file/contents through a session bean to the bean client

Hi All,
I'm a newbie to enterprise beans and facing a problem. I have a requirement where an excel file saved on the server will be a accessed by a session bean and return it to the bean client (developed in swing). Client will display the file contents, user edits the contents and saves. Pressing the save button will save the excel on the server again using the same session bean.
As far as displaying the contents of excel on the form/panel is concerned I have developed this part and able to load files and save them on my local machine.
But my main requirement is to load it through Session Bean and then save it back on the server. An EJB 2.0 code snippet addressing this part would be a great help.
Thanks,

and where's the problem?
I see 2 EJB calls, one to retrieve the data and another one to send it back to the server.
That's the simplest scenario, easy to implement using a stateless session bean (though if you want to prevent concurrent modification of the file there's a bit more work to do, like keeping a record of open files).
A more complex solution would have the client send only the changes to the file (for network performance reasons maybe) and have the EJB merge those in some way with the original document.
Complex, possibly error prone, probably not worth the effort.
First scenario should pose no problem if you're familiar with Java and have a passing familiarity with EJB.

Dynamic session bean call

During our development, we're going to call some session beans, but not by the normal way. We have the session bean A, that contains some data such like the name for the remote and home interface and JNDI Name for a session bean B. It also contains the name of a method that shall be called in the session bean B. We can call the method using the specific classes for that (Class, Method, invoke, and so on). Our matter is: how to refer the session bean B in the "ejb-jar.xml" (and in "jboss.xml", since we use JBoss 3.0.0)? To invoke the session bean B, it must exist an "<ejb-ref>" tag in the "ejb-jar.xml", so that I can call the lookup and the session bean is found.
Can anybody help us, or tell where can we find some help?
Thanks,
Jonatan Schroeder
Medisoft - Brazil

Hi
Now I have the same problem that you. Did you solve that?
I would appreciate your answer
Thanks in advance,
Juan

RMI server object lookup in a session bean

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