Reset session bean

Hi,
I am in the situation where I have to fill in some data on page one, this data is saved in a session managed bean and used in a second page.
After finishing page two the proces is done and the user should be redirected to a new empty first page again.
The problem that I run into is when I use a navigation-rule to navigate back to the first the original data is still there. Offcourse it is possible to clear all items one by one but what I like to know if there is a way to clear all data at once (reset sessionbean??)
Thanks Erik

Do you want to reset your session or just the one session bean?
When the user clicks the button to complete the process, you can easily do either one of these. In the action method that is executed upon the button click add the following code:
For resetting your session:
          //Reset current state of application (for the current user) by
          //invalidating the session
          HttpSession session = (HttpSession)FacesContext.getCurrentInstance().
               getExternalContext().getSession(false);
          if (session != null)
               session.invalidate();For resetting just one Session bean:
          FacesContext.getCurrentInstance().getExternalContext().
               getSessionMap().remove("beanName");Easy eh?
CowKing

Similar Messages

Reset Session Scope Bean

Hey guys. For complicated reasons I need to reset a session scope bean. Can anyone point me in the right direction on how to accomplish this?
Rather new to beans.

well,
I declared the filter in the web.xml
<filter>
     <filter-name>filterMyfilter</filter-name>
     <filter-class>
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</filter>
<filter-mapping>
     <filter-name>filterMyfilter</filter-name>
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package filters;
imports...
public class Myfilter implements javax.servlet.Filter {
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     public void doFilter(ServletRequest req, ServletResponse resp,
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thanks in advance.

Stateless Session Bean has no Context when called from WAR

Hello,
Here is the code for my stateless session bean (it will carry out certain actions based on the timer service)
package DigestTest;
import java.io.BufferedWriter;
import java.io.FileWriter;
import java.util.Date;
import javax.ejb.*;
import javax.ejb.TimedObject;
import javax.ejb.Timer;
* This is the bean class for the MasterTimerBean enterprise bean.
* Created Sep 7, 2006 9:05:09 AM
* @author ttaylor
public class MasterTimerBean implements SessionBean, MasterTimerRemoteBusiness, MasterTimerLocalBusiness, TimedObject
private SessionContext context;
public void setSessionContext(SessionContext aContext)
context = aContext;
* @see javax.ejb.SessionBean#ejbActivate()
public void ejbActivate()
* @see javax.ejb.SessionBean#ejbPassivate()
public void ejbPassivate()
* @see javax.ejb.SessionBean#ejbRemove()
public void ejbRemove()
// </editor-fold>
* See section 7.10.3 of the EJB 2.0 specification
* See section 7.11.3 of the EJB 2.1 specification
public void ejbCreate()
// TODO implement ejbCreate if necessary, acquire resources
// This method has access to the JNDI context so resource aquisition
// spanning all methods can be performed here such as home interfaces
// and data sources.
public void ejbTimeout(Timer timer)
try
BufferedWriter writer = new BufferedWriter(new FileWriter("C:\\timerTest.txt"));
writer.write("Timer has tripped");
writer.newLine();
writer.flush();
writer.close();
catch(Exception e)
return;
// Add business logic below. (Right-click in editor and choose
// "EJB Methods > Add Business Method" or "Web Service > Add Operation")
public String initializeTimer()
String result = "\n\nInitializing Timer\n";
try
// Create Your Timer
if(context!=null)
TimerService ts = context.getTimerService();
result = result+"Instantiating Timer Object\n";
Timer timer = ts.createTimer(new Date(), 5000, "TestTimer");
result = result+"About to grab TimerHandle";
TimerHandle timerHandle = timer.getHandle();
else
result = result+"\nContext Object is null\n";
catch (Exception e)
result = result+"\nError:\n"+e.toString();
return result;
public String writerTest()
String result = "about to write";
try
result = result+"\nOpening the file";
BufferedWriter writer = new BufferedWriter(new FileWriter("C:\\timerTest.txt"));
result = result+"\nWriter Test Passed";
writer.write("Writer Works");
writer.newLine();
result = result+"\nFlushing writer";
writer.flush();
result = result+"\nClosing writer";
writer.close();
catch (Exception e)
result = result+"\n"+e.toString();
return result;
I am calling initializeTimer() from a jsp page with a simple <jsp:useBean tag>.
The program keeps returning that the context variable is not set(this is from the context!=null conditional in initializeTimer()). I am very confused, I thought that setContext(...) was called by the container upon instantiation (and thus should happen completely without any action from me).
How am I able to call a session bean that has not had the context set?
Any information is appreciated,
Thanks,
Scott

thank you for your reply, rajeevm007.
it seems that the question is really a problem now.
i think i should update weblogic to the lastest version and confirm this question. if it still in there, it seems that we have to reset the global variables all manually. so, now, we are discussing that should we modify all the ejbs, or wait the next version of weblogic. :) of cause the second choice is a joke.
no other good choice?
maybe in the march of the next year....
cheers
thank you again.

How can i design a EJB application using session Beans?

Hello,
I am designing a Find application using EJB. Here a user is prompted a search page, where he can enter the search criteria's. Then on click of submit, the query is formed at the server side depending on what criteria's were selected. Then a jdbc query is performed and the results are returned back to the user. Here no session is maintained for the users. Can anyone suggest me how to design this application using EJB. Should i use entity beans for this or session beans will suffice? Should the jdbc query be performed in the bean itself or should it be outside in a helper class? Please kindlu suggest me the design for this application...
Regards,
Subbu

Hi,
First of all, I'm unable to figure out why you need to use EJB for this scenario. You can write a helper class to frame and execute the query.
If you really want to use EJB, then I suggest you use a stateless Session Bean with transaction attribute as TX_NOT_SUPPORTED. From the session bean, you can call the helper class. But, by avoiding the session bean, you can eliminate remote calls, thus improving your performance. Also, check if the database & the db driver you are using supports sql caching.
Regards,
Raj.

Error while adding a new method to the Session Bean

Hello everyone. I'm using jdev 11g, ejb, jpa & jsf. Everything works fine. But when I try to add a custom method to the Session Bean, I'm having an error.
Here is my steps:
1) I added a new method to SessionBean.java. Something like this:
public void Hello() {
System.out.println("Hello!");
2) Then using Structure palette I exposed this method through Local interface and created data control
3) Finally, I made a command button binded to this method (just droped it from DataControls.dcx to my page)
When I start the page and click the button, I'm having the following error:
Error 500--Internal Server Error
javax.faces.el.EvaluationException: Method not found: Hello.execute(javax.faces.event.ActionEvent)
     at org.apache.myfaces.trinidadinternal.taglib.util.MethodExpressionMethodBinding.invoke(MethodExpressionMethodBinding.java:58)
     at org.apache.myfaces.trinidad.component.UIXComponentBase.broadcastToMethodBinding(UIXComponentBase.java:1227)
     at org.apache.myfaces.trinidad.component.UIXCommand.broadcast(UIXCommand.java:183)
     at oracle.adf.view.rich.component.fragment.ContextSwitchingComponent$1.run(ContextSwitchingComponent.java:70)
... (I've truncated the log because there is nothing important in the missing part)

Yes, I have binding in the page def. Everything is correct there:
<methodAction id="Hello" RequiresUpdateModel="true" Action="invokeMethod"
MethodName="Hello" IsViewObjectMethod="false"
DataControl="PriceServiceLocal"
InstanceName="PriceServiceLocal.dataProvider"/>
I've droped the method from the Data Controls panel

Calling EJB 3.0 Stateless Session Bean

Dear all,
I created a stateless session bean with a hello world method on it. Now i want to call the method from a BeanDecorator class, through a getter metod. When i use the jndi lookup in my getter, i can call the helloWorld method without a problem. However, when i dont use the jndi lookup, and only use the @EJB annotation, i always get a nullpointer.
This is working:
InitialContext ic = new InitialContext();
test = (TestLocal)ic.lookup("test.be/ear~bd/LOCAL/TestBean/"+TestLocal.class.getName());
test.helloWorld()
This gives nullpointer:
@EJB
private TestLocal test;
test.helloWorld();
What is the correct way to consume session beans without having to explicitly code the jndi lookup?
Kind regards.

Hi,
any annotation like this can be used only in "managed classes" like Session Beans, Servlets etc. Managed classes are those classes managed by the J2EE server. Managed here means, lifetime controlled by server.
You can find this in J2EE specification.
Frank

EJB 3.0 - Communicate an Applet with a Session Bean

Hello
I'm developing an EJB 3.0 app (eclipse and glassfish tools bundle), and I have an applet that has to use remote session beans.
QUESTION: Is it possible for the applet to connect to EJB?
QUESTION: By creating a J2EE application client project, can I use @EJB annotations to inject the session bean directly to the applet, avoiding the JNDI lookup?
(since I imagine that the anwser to the second one is NO, I do the following consideration)
Given an application client project, I imagine that this application can run remotely on a client machine/JRE. Then this application can use Annotations/injection facilities whenever it runs on a J2EE client container (which I assume consists of a set of libraries provided by the application server vendor, Glassfish in that case). Could this application be deployed using Java Web Start? If so, why can't it be deployed as an applet? (both options run in a client JRE, don't they?).
QUESTION: In either case (applet or JWS), how do I have to package the JAR file (using Eclipse) so that it contains the needed libraries for accessing the EJB? Which are those libraries?
At the time being, I'm trying to implement a sample application that follows the "Applet doing JNDI lookup" approach. I have:
- an EAR project
- an EJB project (containing an Entity Bean and a Stateless Session Bean with a @Remote interface)
@Remote
public interface HelloRemote {
     public String hello(String name);
@Stateless
public class Hello implements HelloRemote {
     @Override
     public String hello(String name) {
          return "Hello "+name+"!!";
}- an Application Client project (containing the applet code):
public class ClientApplet extends JApplet {
     public void init(){
          try {
               Context jndiContext = getInitialContext( );
               HelloRemote server = (HelloRemote) jndiContext.lookup(HelloRemote.class.getName());
               setContentPane(new JLabel(server.hello("Gerard")));
          } catch (NamingException e) {
               // TODO Auto-generated catch block
               e.printStackTrace();
     private Context getInitialContext() throws NamingException{
          Properties props = new Properties();
          props.setProperty("java.naming.factory.initial", "com.sun.enterprise.naming.SerialInitContextFactory");
          props.setProperty("org.omg.CORBA.ORBInitialHost", "myhost");
          props.setProperty("org.omg.CORBA.ORBInitialPort", "3700");
          return new InitialContext(props);
}- a static web project (with a sample web page that contains the applet object the corresponding applet JAR file)
I tried to export the Application Client project as an "application client JAR", in the hope that the java EE libraries bundled with glassfish (listed as libraries of this project) would be packaged too.
No success, so now I'll try to copy all the JAR files (one by one) into the +\WebContent\+ folder of the Web Project, and add references to each of them in the archive="" attribute of the +<applet>+ HTML tag. Although this might work, I suspect that I am missing the good/easy way of doing it. Any suggestions?
Thanks in advance,
Gerard
Edited by: gsoldevila on May 6, 2009 7:09 AM

An Applet can communicate with an EJB via JNDI lookup but I would (personally) use an intermediate Servlet to handle this. Client to Servlet communication is http whereas to ejb is iiop - which might be blocked.
Injection only works in managed classes (EJB, Servlet, Listeners..) and an Application Client main class. So yes you could use an app client for handling resource injection.
m

Calling Enity Bean's business methods from a session bean in EJB 3.0 specif

Hello everybody,
Happy to be a member with you in this forum.
This is my first participation in this forum.
I have some problem to start with EJB 3.0 specification, I have created an entity bean with some business methods that access a mysql datbase, then i want to create a stateful session bean to provide the client an interface to consume business methods in Enity be
Please can someone you help me with an example

@Vladimir Pavlov
I did not understand what you are trying to convey...
Whenever an attribute of this bean is modified we want to access that latest value.... Is there any way to know, when the attribute is modified? Just with get/set we can not know, when it is modified... am i right?
We want to achieve this without modifying the existing source code of the EJB....
@ Ivo Simeonov
As of my knowledge, to use interceptors we need to modify the EJB source code, but we do not want to touch the source code....
All this has to be achieved dynamically when the application is deployed in the production.... is it possible???

How to use jta in toplink and stateless session bean EJB 3.0?

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In web side ı want to use two methods in stateless session bean which are updated
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I also want to JTA in web side. My first methods is done correctly, but second method has an error. I wanto to rollback all transaction.
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Yuichi
Did you manage to solve this? I'm doing something similar and seeing the same problem, although they're up to 7.3 SP7.
Any help greatly appreciated.
Lewis

Problem calling a session bean (EJB 3.0)

Hello,
I'm new to netbeans and J2EE. I'm using NetBeans 5.5 Beta 2 and sun application server 9 pe.
I created a new enterprise application and i'm trying to access a Session Bean (Remote and Stateless)
from the app-client (outside the main class).
This is the loockup method that was generated by the IDE (Enterprise Resources > Call enterprise bean):
private ejb.SessionBeanDoenteRemote lookupSessionBeanDoenteBean() {
try {
javax.naming.Context c = new javax.naming.InitialContext();
return (ejb.SessionBeanDoenteRemote) c.lookup("java:comp/env/ejb/SessionBeanDoenteBean");
catch(javax.naming.NamingException ne) {
java.util.logging.Logger.getLogger(getClass().getName()).log(java.util.logging.Level.SEVERE,"exception caught" ,ne);
throw new RuntimeException(ne);
When I run the application and try to invoke the lookup method my application gets the following exception:
SEVERE: exception caught
javax.naming.NameNotFoundException: No object bound to name java:comp/env/ejb/Se
ssionBeanDoenteBean
at com.sun.enterprise.naming.NamingManagerImpl.lookup(NamingManagerImpl.
java:751)
at com.sun.enterprise.naming.java.javaURLContext.lookup(javaURLContext.j
ava:156)
at com.sun.enterprise.naming.SerialContext.lookup(SerialContext.java:307
at javax.naming.InitialContext.lookup(InitialContext.java:351)
at intensivecare.entrada.JDialogEntrada.lookupSessionBeanDoenteBean(JDia
logEntrada.java:219)
at intensivecare.entrada.JDialogEntrada.buttonMenuGravarActionPerformed(
JDialogEntrada.java:79)
at intensivecare.JDialogWizzard$2.jButtonGravarActionPerformed(JDialogWi
zzard.java:178)
at componentes.JTaskPanelMenu$3.actionPerformed(JTaskPanelMenu.java:54)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:18
49)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.jav
a:2169)
Please... can someone help me?

The portable way to acquire the dependency is through java:comp/env or @EJB. Accessing the
global namespace directly is not recommended. If you use an ejb-ref, you need to define it
in the component environment within which you'll be looking up the dependency. So if you're
looking it up from an Application Client, you'll need to define the ejb-ref in application-client.xml.
Also, the ejb-ref-name is the portion of the string after java:comp/env. There is no automatic
"ejb" appended to it. If you do ic.lookup("java:comp/env/foo"), your ejb-ref-name would be "foo".
You can use @EJB but it can only be defined in certain managed classes such as the
Application Client main class.
You can find additional info in our EJB FAQ :
https://glassfish.dev.java.net/javaee5/ejb/EJB_FAQ.html
--ken

Error while calling a Web Service from a Session Bean

I am trying to call a Web Service from a Session Bean using an Axis client, but I am getting the next exception:
java.rmi.ServerException: RemoteException occurred in server thread; nested exception is:
     java.rmi.RemoteException: org/apache/axis/client/Service
     at com.sun.corba.ee.internal.javax.rmi.CORBA.Util.wrapException(Util.java:364)
     at javax.rmi.CORBA.Util.wrapException(Util.java:277)
     at com.ing.mx.seguros.siniestros.litigios.ejb._SisaServiceRemote_Stub.invocarWebSericeProveedorLegal(Unknown Source)
     at com.ing.mx.seguros.siniestros.litigios.proxy.SisaWsProxy.solicitarApoyoLegal(SisaWsProxy.java:132)
     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
     at java.lang.reflect.Method.invoke(Method.java:324)
     at org.apache.axis.providers.java.RPCProvider.invokeMethod(RPCProvider.java:402)
     at org.apache.axis.providers.java.RPCProvider.processMessage(RPCProvider.java:309)
     at org.apache.axis.providers.java.JavaProvider.invoke(JavaProvider.java:333)
     at org.apache.axis.strategies.InvocationStrategy.visit(InvocationStrategy.java:71)
     at org.apache.axis.SimpleChain.doVisiting(SimpleChain.java:150)
     at org.apache.axis.SimpleChain.invoke(SimpleChain.java:120)
     at org.apache.axis.handlers.soap.SOAPService.invoke(SOAPService.java:481)
     at org.apache.axis.server.AxisServer.invoke(AxisServer.java:323)
     at org.apache.axis.transport.http.AxisServlet.doPost(AxisServlet.java:854)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:760)
     at org.apache.axis.transport.http.AxisServletBase.service(AxisServletBase.java:339)
     at javax.servlet.http.HttpServlet.service(HttpServlet.java:853)
     at org.apache.catalina.core.StandardWrapperValve.invokeServletService(StandardWrapperValve.java:720)
     at org.apache.catalina.core.StandardWrapperValve.access$000(StandardWrapperValve.java:118)
     at org.apache.catalina.core.StandardWrapperValve$1.run(StandardWrapperValve.java:278)
     at java.security.AccessController.doPrivileged(Native Method)
     at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:274)
     at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:505)
     at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:212)
     at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:505)
     at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:203)
     at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:505)
     at com.iplanet.ias.web.connector.nsapi.NSAPIProcessor.process(NSAPIProcessor.java:158)
     at com.iplanet.ias.web.WebContainer.service(WebContainer.java:850)Thanks for any help provided.
Does any one have insights about it?

Hi Swapna,
from your screenshot it seems that you actually try to call the service in your Data Source Expression field. You should set path to the WSDL file here actually - this could be either URL to SAP or to filesystem, as Anton suggested (this could be faster). Have you created endpoint binding for your service in transaction SOAMANAGER? If yes, then simply download the corresponding WSDL with binding or copy the URL which leads to it. But also test whether you are able to retrieve the WSDL without logging into SAP (close all browser windows and then open a new one otherwise session ID from other browser windows can be reused).
If you have to give username and password, then setup anonymous alias in transaction SICF, for example.
Pleas, check my previous post on the same subject here: Re: BCM7 IVR : SOAP request for client identification in CRM .
Maybe it could help.
Regards,
Dawood.

Error while Look up session bean (EJB 3.0) in WebDynpro

hi ,
             I want to look up session bean inside webdynpro. I hv written following code inside init of component controller. but not able to look up session bean
try{
               InitialContext context = new InitialContext();
               ApplicationFetcherLocal applicationFetcherLocal = null;
             applicationFetcherLocal = (ApplicationFetcherLocal)context.lookup((ApplicationFetcherLocal.class.getName());
          catch (Exception ex){
               System.err.println("LookUp Failed\n\n"+ex.getMessage());

Have you read my latest reply in your other [thread|session bean look up across DCs in EJB3.0;?
What's the value of asking the same question again if you don't care about the answer?
Regards,
-- Vladimir

Accessing the same stateful session bean from multiple clients in a clustered environment

I am trying to access the same stateful session bean from multiple
          clients. I also want this bean to have failover support so we want to
          deploy it in a cluster. The following description is how we have tried
          to solve this problem, but it does not seem to be working. Any
          insight would be greatly appreciated!
          I have set up a cluster of three servers. I deployed a stateful
          session bean with in memory replication across the cluster. A client
          obtains a reference to an instance of one of these beans to handle a
          request. Subsequent requests will have to use the same bean and could
          come from various clients. So after using the bean the first client
          stores the handle to the bean (actually the replica aware stub) to be
          used by other clients to be able to obtain the bean. When another
          client retrieves the handle gets the replica aware stub and makes a
          call to the bean the request seems to unpredictably go to any of the
          three servers rather than the primary server hosting that bean. If the
          call goes to the primary server everything seems to work fine the
          session data is available and it gets backed up on the secondary
          server. If it happens to go to the secondary server a bean that has
          the correct session data services the request but gives the error
          <Failed to update the secondary copy of a stateful session bean from
          home:ejb20-statefulSession-TraderHome>. Then any subsequent requests
          to the primary server will not reflect changes made on the secondary
          and vice versa. If the request happens to go to the third server that
          is not hosting an instance of that bean then the client receives an
          error that the bean was not available. From my understanding I thought
          the replica aware stub would know which server is the primary host for
          that bean and send the request there.
          Thanks in advance,
          Justin


          If 'allow-concurrent-call' does exactly what you need, then you don't have a problem,
          do you?
          Except of course if you switch ejb containers. Oh well.
          Mike
          "FBenvadi" <[email protected]> wrote:
          >I've got the same problem.
          >I understand from you that concurrent access to a stateful session bean
          >is
          >not allowed but there is a
          >token is weblogic-ejb-jar.xml that is called 'allow-concurrent-call'
          >that
          >does exactly what I need.
          >What you mean 'you'll get a surprise when you go to production' ?
          >I need to understand becouse I can still change the design.
          >Thanks Francesco
          >[email protected]
          >
          >"Mike Reiche" <[email protected]> wrote in message
          >news:[email protected]...
          >>
          >> Get the fix immediately from BEA and test it. It would be a shame to
          >wait
          >until
          >> December only to get a fix - that doesn't work.
          >>
          >> As for stateful session bean use - just remember that concurrent access
          >to
          >a stateful
          >> session bean is not allowed. Things will work fine until you go to
          >production
          >> and encounter some real load - then you will get a surprise.
          >>
          >> Mike
          >>
          >> [email protected] (Justin Meyer) wrote:
          >> >I just heard back from WebLogic Tech Support and they have confirmed
          >> >that this is a bug. Here is their reply:
          >> >
          >> >There is some problem in failover of stateful session beans when its
          >> >run from a java client.However, it is fixed now.
          >> >
          >> >The fix will be in SP2 which will be out by december.
          >> >
          >> >
          >> >Mike,
          >> >Thanks for your reply. I do infact believe we are correctly using
          >a
          >> >stateful session bean however it may have been misleading from my
          >> >description of the problem. We are not accessing the bean
          >> >concurrently from 2 different clients. The second client will only
          >> >come into play if the first client fails. In this case we want to
          >be
          >> >able to reacquire the handle to our stateful session bean and call
          >it
          >> >from the secondary client.
          >> >
          >> >
          >> >Justin
          >> >
          >> >"Mike Reiche" <[email protected]> wrote in message
          >news:<[email protected]>...
          >> >> You should be using an entity bean, not a stateful session bean
          >for
          >> >this application.
          >> >>
          >> >> A stateful session bean is intended to be keep state (stateful)
          >for
          >> >the duration
          >> >> of a client's session (session).
          >> >>
          >> >> It is not meant to be shared by different clients - in fact, if
          >you
          >> >attempt to
          >> >> access the same stateful session bean concurrently - it will throw
          >> >an exception.
          >> >>
          >> >> We did your little trick (storing/retrieving handle) with a stateful
          >> >session bean
          >> >> on WLS 5.1 - and it did work properly - not as you describe. Our
          >sfsb's
          >> >were not
          >> >> replicated as yours are.
          >> >>
          >> >> Mike
          >> >>
          >> >> [email protected] (Justin Meyer) wrote:
          >> >> >I am trying to access the same stateful session bean from multiple
          >> >> >clients. I also want this bean to have failover support so we want
          >> >to
          >> >> >deploy it in a cluster. The following description is how we have
          >tried
          >> >> >to solve this problem, but it does not seem to be working. Any
          >> >> >insight would be greatly appreciated!
          >> >> >
          >> >> >I have set up a cluster of three servers. I deployed a stateful
          >> >> >session bean with in memory replication across the cluster. A client
          >> >> >obtains a reference to an instance of one of these beans to handle
          >> >a
          >> >> >request. Subsequent requests will have to use the same bean and
          >could
          >> >> >come from various clients. So after using the bean the first client
          >> >> >stores the handle to the bean (actually the replica aware stub)
          >to
          >> >be
          >> >> >used by other clients to be able to obtain the bean. When another
          >> >> >client retrieves the handle gets the replica aware stub and makes
          >> >a
          >> >> >call to the bean the request seems to unpredictably go to any of
          >the
          >> >> >three servers rather than the primary server hosting that bean.
          >If
          >> >the
          >> >> >call goes to the primary server everything seems to work fine the
          >> >> >session data is available and it gets backed up on the secondary
          >> >> >server. If it happens to go to the secondary server a bean that
          >has
          >> >> >the correct session data services the request but gives the error
          >> >> ><Failed to update the secondary copy of a stateful session bean
          >from
          >> >> >home:ejb20-statefulSession-TraderHome>. Then any subsequent requests
          >> >> >to the primary server will not reflect changes made on the secondary
          >> >> >and vice versa. If the request happens to go to the third server
          >that
          >> >> >is not hosting an instance of that bean then the client receives
          >an
          >> >> >error that the bean was not available. From my understanding I
          >thought
          >> >> >the replica aware stub would know which server is the primary host
          >> >for
          >> >> >that bean and send the request there.
          >> >> >
          >> >> >Thanks in advance,
          >> >> >Justin
          >>
          >
          >

Declarative Transactions, Session Beans & JDBC

Hi (this is really a newbie question),
If I executed an SQL Update statement in a Stateless Session Bean via JDBC,
is my call to the database enlisted in the container transaction
automatically? (Of course, I am assuming the correct TxRequired settings
are set on the deployment descriptors for the Session Bean.)
Asked in another way, how does JDBC "talk" to the EJB container to let it
know that it is being called within a Transactional Context and that all
activities with the database should then be enlisted in a transaction
automatically? Where does this "smartness" come in? Or does this not happen
at all - do I have to "obtain" the JDBC connection object from the EJB
container instead of writing directly to JDBC?
Thanks in advance,
Abdullah Kauchali

Correct.
I'd also recommend (where possible), doing the DataSource JNDI lookup in
your setSessionContext method and storing it away in a member variable.
There's usually no reason to do it on every method call.
-- Rob
Abdullah Kauchali wrote:
Okay,
After some investigations, this is what I've learned:
1. To get automatic transactional enlistment (in a distributed tx), you
have to make your EJB container aware of the JDBC datasource (viz. you have
to create a Transactional DataSource). This is done by creating necessary
entries in a configuration XML file so that the container can connect to the
JDBC datasource when fired-up;
2. You then only create your Connection object via a reference (JNDI to be
exact) to the connection object and NOT directly with JDBC (this was my
confusion in fact). Something like this:
//obtain the conduit to the JNDI resource manager factory
javax.sql.DataSource objDS = (javax.sql.DataSource)
context.lookup("~some jndi
reference~");
//now get the connection object - notice no "javax" but "java"
java.sql.Connection objCon = objDS.getConnection();
3. By doing 2. above you are actually using a "Resource Manager Connection
Factory" to get your Connection object for subsequent SQL Updates;
4. As long as your JDBC driver supports the javax.sql.DataSource interface
and provided Transactional Context is propagated from any root call to your
worker Session Bean, you get automatic transaction enlistment of the SQL
Updates with your EJB container;
Please correct me if I have concluded wrongly,
Regards
Abdullah
"Abdullah Kauchali" <ak@ak> wrote in message
news:[email protected]...
Hi (this is really a newbie question),
If I executed an SQL Update statement in a Stateless Session Bean viaJDBC,
is my call to the database enlisted in the container transaction
automatically? (Of course, I am assuming the correct TxRequired settings
are set on the deployment descriptors for the Session Bean.)
Asked in another way, how does JDBC "talk" to the EJB container to let it
know that it is being called within a Transactional Context and that all
activities with the database should then be enlisted in a transaction
automatically? Where does this "smartness" come in? Or does this nothappen
at all - do I have to "obtain" the JDBC connection object from the EJB
container instead of writing directly to JDBC?
Thanks in advance,
Abdullah Kauchali

How to get the UserTransaction object in stateless session bean

Hi, I am using jboss server and jdk5 version and using EJB.
My Application flow :
JSP à Action(Struts) à Service Locator à Session bean à Entity Bean(cmp) à DB.
I tried to get the UserTransaction object in my Action. Its my code.
InitialContext ctx = new InitialContext();
UserTransaction uTrans = (UserTransaction) ctx.lookup("java:comp/UserTransaction");
After used uTrans.begin(),uTrans.commit() and uTrans. rollback () also.
Its working fine .
But, I used the the same code inside in my session bean its not working.
Stateless Session Manager Bean code :
public class SampleManagerBean implements SessionBean {
public void ejbCreate() throws CreateException { }
public void ejbRemove() { }
public void ejbActivate() {   }
public void ejbPassivate() {   }
public void setSessionContext(SessionContext sessionContext) {
this.sessionContext = sessionContext;
     public void createSample() throws EJBException
     try{
               InitialContext ctx = new InitialContext();
               UserTransaction ut = (UserTransaction) ctx.lookup("java:comp/UserTransaction");
          }catch(Exception e) {
          System.out.println( Exception === > +e)
Its throws the error ie: javax.naming.NameNotFoundException: UserTransaction not bound
How to get the UserTransaction object in my session bean. Kindly give solution the above errors.
- Thendral

first of all, you could just use sessionContext.getUserTransaction(). however, that would only work if your bean is using bean-managed transactions. the default is container-managed transaction, in which case you cannot get a UserTransaction object. if you want to manage transactions, you need to add the TransactionManagementType.BEAN annotation to your ejb.

Reset session bean

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