JNDI lookup in a cluster

Hi,
          The WL documentation contains the following:
          "When clients obtain an initial JNDI context by supplying the cluster DNS
          name, weblogic.jndi.WLInitialContextFactory obtains the list of all
          addresses that are mapped to the DNS name"
          Should clients (e.g. an EJB) be concerned about retrying the call to get the
          Initial Context. In other words, can this call fail if one of the servers in
          the cluster fails?
          After the intital contect is obtained, it seems that the lookup should
          always work (since WL will take care of individual server failures and retry
          the lookup in needed).
          Not clear whether the call to get the initial context is guaranteed to
          succeed (as long as one server in the cluster is up, of course)... Any
          information would be appreciated.
          Thanks,
          Philippe

          Hello Philippe,
          I had posted a similar question but now can't find it...got lost I suppose. Anyway,
          I wanted to add in my findings on this. I have a stateful session object running
          in a clustered setup. This stateful object has Home references to multiple stateless
          beans. When I create a failover my stateful object does its failover properly.
          But, if I don't perform a new Home lookup for the stateless objects needed I receive
          the following error:
          ####<Nov 9, 2001 2:00:06 PM CST> <Error> <> <gwiz> <testServer1> <ExecuteThread:
          '9' for queue: 'default'> <> <> <000000> <<TestDeliveryActionHandler>Problem occured
          when trying to do a save and goto. java.rmi.NoSuchObjectException: Activation
          failed with: java.rmi.NoSuchObjectException: Unable to locate EJBHome: 'GBTestManagerHome'
          on server: 't3://10.1.17.3:7001
          When I perform a lookup during the ejbactivate() method to get a new Home reference
          all seems to work OK. My question though is, is this correct? From what I have
          read I had the same impression that the unserialized Home reference should be
          able to locate a new reference in the cluster without having to perform a lookup
          again.
          Any advice from anyone is greatly appreciated,
          Rich
          "Philippe Fajeau" <[email protected]> wrote:
          >Hi,
          >
          >The WL documentation contains the following:
          >
          >"When clients obtain an initial JNDI context by supplying the cluster
          >DNS
          >name, weblogic.jndi.WLInitialContextFactory obtains the list of all
          >addresses that are mapped to the DNS name"
          >
          >Should clients (e.g. an EJB) be concerned about retrying the call to
          >get the
          >Initial Context. In other words, can this call fail if one of the servers
          >in
          >the cluster fails?
          >
          >After the intital contect is obtained, it seems that the lookup should
          >always work (since WL will take care of individual server failures and
          >retry
          >the lookup in needed).
          >
          >Not clear whether the call to get the initial context is guaranteed to
          >succeed (as long as one server in the cluster is up, of course)... Any
          >information would be appreciated.
          >
          >Thanks,
          >
          >Philippe
          >
          >

Similar Messages

How to create InitialContext for JNDI lookup in a cluster?

          I am new to clusters in WL7 and I wanted to know how a client would create an InitialContext
          object to perform a JNDI lookup for a remote object deployed across serveral servers
          in the cluster. Is the following correct?
          Physcial Servers in the cluster
          machine1:9001
          machine2:9001
          machine3:9001
          Code for creating InitialContext
          Properties p = new Properties();
          p.put(Context.INITIAL_CONTEXT_FACTORY, "weblogic.jndi.WLInitialContextFactory");
          p.put(Context.PROVIDER_URL, "machine1:9001,machine2:9001,machine3:9001");
          Context c = new InitialContext( p);
          Thanks,
          Raffi


Hi Ivaylo,
There's another alternative solution to your problem. You can have the screen 120 as a user-defined selection screen. i.e., instead of creating this screen through the screen painter, you can create it from within your ABAP Program. This way, you can directly use the SELECT-OPTIONS statement within your screen. You then will no longer have to bother about how to handle the data for the field.
Especially in the case where your screen 120 has few elements, this approach, in my opinion, will be the best.
Please let me know if you need any further clarifications on how to go about it if you choose to follow this approach.
Regards,
Anand Mandalika.

JAVA client JNDI lookup for EJB session in cluster in WLS 5.1

The documentation says :
          to obtain a Context for JNDI lookup do the following :
          Hashtable ht = new Hashtable();
          ht.put(Context.INITIAL_CONTEXT_FACTORY,
          "weblogic.jndi.WLInitialContextFactory");
          ht.put(Context.PROVIDER_URL, "t3://mycluster:7001");
          try {
          Context ctx = new InitialContext(ht);
          // Do the client's work
          catch (NamingException ne) {
          // A failure occurred
          finally {
          try {ctx.close();}
          catch (Exception e) {
          // a failure occurred
          where "mycluster" is the DNS name of my cluster. My DNS server (Windows 200
          DNS server) use round robin
          to call alernatively all the wls server node in "mycluster" and it's OK. The
          two servers of my cluster
          are called alternatively for my EJB session stateless.
          Now I unplug one of the two nodes of my cluster and the remaining server is
          called only 2 times
          and not after.
          Questions :
          -is the load balancing between the nodes of mycluster only rely on DNS or
          is there an internal
          mecanism in EJB sub to try one server then an other ?
          - do I need to obtain a new reference on JNDI Context for each call ?
          Thank's a lot.
          Farid Bellameche.


          I too have the same problem. My scenario is :
          I have the web tier architecture away from cluster. All ejbs are in cluster
          running in two seperate machines. We have a factory class running in
          webtier(we use servlet in this tier) which obtains home interface only once
          and stores it for future reference. When ever we need the remoteobject stub,
          we ask the factory class and which in turn uses the stored home interface to
          get the same.
          In the webtier, I list all the servers in the cluster as a part of url as
          mentioned by you.
          I started the web tier as well as Object tier cluster. I could see the
          request coming in both the machines in the cluster for the ejb. But When I
          bring one the server in the cluster,
          1. Web tier throws an exception saying that it could not connect
          to server using t3.
          2. The other machine which is running the server, also says
          'failed to create socket to : -32323234324 sever name
          using protocol t3.
          It looks like I am able to get load balance. But I am not able to get the
          fail over to be working.
          In the weblogic-ejb-jar.xml, I added the following.
          <clustering-descriptor>
          <home-is-clusterable>true</home-is-clusterable>
          <home-load-algorithm>round-robin</home-load-algorithm>
          </clustering-descriptor>
          I compiled and added the .jar file. So the jar file now has replica aware
          stubs.
          Could any one of you help me for why the fail over is not working?
          Suersh
          "Giri Alwar" <[email protected]> wrote in message
          news:[email protected]...
          > Farid,
          > (1) Yes, the stub has the logic to perform load-balancing and
          fail-over.
          > (2) In almost all cases, no. You can get the context once, store it
          and
          > use it thereafter. Please refer to
          > http://www.weblogic.com/docs51/cluster/concepts.html#1025061 for more
          info.
          >
          > A couple of notes on your situation. From what you are describing, your
          > Windows DNS server is setup to serve only one IP from the cluster (using
          > round-robin) as opposed to a list of all IP's in the cluster. Hence, the
          > initial context you obtain is tied to a single server in the cluster (the
          > one returned by the DNS). The weblogic implementation on the client side
          has
          > no idea of the existence of the other servers in the cluster. This is not
          a
          > cluster aware context. To obtain a cluster aware context, either list all
          > the IP's in the URL like t3://server1,server2,server3:7001 or have
          > "mycluster" return a list of all servers in the cluster.
          >
          > Giri
          >
          >
          > "Farid Bellameche" <[email protected]> wrote in message
          > news:[email protected]...
          > > The documentation says :
          > >
          > > to obtain a Context for JNDI lookup do the following :
          > > Hashtable ht = new Hashtable();
          > > ht.put(Context.INITIAL_CONTEXT_FACTORY,
          > > "weblogic.jndi.WLInitialContextFactory");
          > > ht.put(Context.PROVIDER_URL, "t3://mycluster:7001");
          > > try {
          > > Context ctx = new InitialContext(ht);
          > > // Do the client's work
          > > }
          > > catch (NamingException ne) {
          > > // A failure occurred
          > > }
          > > finally {
          > > try {ctx.close();}
          > > catch (Exception e) {
          > > // a failure occurred
          > > }
          > > }
          > >
          > > where "mycluster" is the DNS name of my cluster. My DNS server (Windows
          > 200
          > > DNS server) use round robin
          > > to call alernatively all the wls server node in "mycluster" and it's OK.
          > The
          > > two servers of my cluster
          > > are called alternatively for my EJB session stateless.
          > > Now I unplug one of the two nodes of my cluster and the remaining server
          > is
          > > called only 2 times
          > > and not after.
          > >
          > > Questions :
          > > -is the load balancing between the nodes of mycluster only rely on DNS
          > or
          > > is there an internal
          > > mecanism in EJB sub to try one server then an other ?
          > >
          > > - do I need to obtain a new reference on JNDI Context for each call ?
          > >
          > >
          > > Thank's a lot.
          > >
          > > Farid Bellameche.
          > >
          > >
          > >
          > >
          >
          >

EJB 3.0 and jndi lookup (simple question)

hi all,
i am newbie on Weblogic Application Server and i have some issues,
i have weblogic application server 10.0, also i have oracle timesten in-memory database, i have configured datasource and deploy my ejb 3.0 application, but i could not done jndi lookup?
here is my example:
1. one stateless session bean :
import javax.ejb.Remote;
@Remote
public interface InsertSubscriber {
     public void insertSubscriber(SubscriberT subscriberT);
} 2. here is it's implementation :
@Remote(InsertSubscriber.class)
@Stateless
public class InsertSubscriberBean implements InsertSubscriber {
     @PersistenceContext(unitName = "TimesTenDS")
     private EntityManager oracleManager;
     public void insertSubscriber(SubscriberT subscriber)
          try {
               System.out.println("started");
               oracleManager.persist(subscriber);
               System.out.println("end");
          } catch (Exception e) {
               e.printStackTrace();
}3 and my test client :
public class Client {
     public static void main(String[] args) {
          Context ctx = null;
          Hashtable ht = new Hashtable();
          ht.put(Context.INITIAL_CONTEXT_FACTORY,
                    "weblogic.jndi.WLInitialContextFactory");
          ht.put(Context.PROVIDER_URL, "t3://192.9.200.222:7001");
          try {
               ctx = new InitialContext(ht);
               InsertSubscriber usagefasade = (InsertSubscriber) ctx
                         .lookup("ejb.InsertSubscriberBean");
          } catch (NamingException e) {
               e.printStackTrace();
          } finally {
               try {
                    ctx.close();
               } catch (Exception e) {
                    e.printStackTrace();
}what i did incorrect ???
i got error like this : Name not fount exception
when i tried to view jndi tree on weblogic server application console i found this :
     Binding Name:
TimestenExampleTimestenExample_jarInsertSubscriberBean_InsertSubscriber
     Class:
test.InsertSubscriberBean_o7jk9u_InsertSubscriberImpl_1000_WLStub
     Hash Code:
286
     toString Results:
weblogic.rmi.internal.CollocatedRemoteRef - hostID: '2929168367193491522S::billing_domain:AdminServer', oid: '286', channel: 'null'what does it mean how i can done lookup to jndi ?
Regards,
Paata Lominadze,
Magticom LTD.
Georgia.

Hi All,
I am using the weblogic cluster with session replication and EJB 2.0 with Local entity beans.
for fail-over session should be replicated to another server so we can achive the same session if 1st server fails.
Suppose i m using two managed server(server1,server2) in the cluster.I am storing the object of class ABC into session and object contains the instance of Local-EntityBean home but i put that as a transient.I have also override the readObject and write object method.
when write object is called on 1st server,readObject method should be called on second server so we will be sure that session is replicating properly.
pleaase find the code below : -
public IssuerPageBean() {
initEJB();
private void readObject(java.io.ObjectInputStream stream) throws IOException, ClassNotFoundException {
stream.defaultReadObject();
initEJB();
initializeCommonObject();
private void writeObject(java.io.ObjectOutputStream stream) throws IOException {
stream.defaultWriteObject();
private void initEJB() {
try {
ic = new InitialContext();
issuerHome = (LocalIssuerHome) ic.lookup("java:comp/env/Issuer");
} catch (NamingException e) {
e.printStackTrace();
in my case if i am calling the constructor IssuerPageBean(),it calls the initEJB() method and lookeup the entity local home properly but when readObject method is called on another server only initEJB() method is called directly and getting the exception below :
WARNING: Error during create -
javax.naming.NameNotFoundException: remaining name: env/ejb/Client
at weblogic.j2eeclient.SimpleContext.resolve(Ljavax/naming/Name;Z)Ljavax/naming/Context;(SimpleContext.java:35)
at weblogic.j2eeclient.SimpleContext.resolve(Ljavax/naming/Name;)Ljavax/naming/Context;(SimpleContext.java:39)
at weblogic.j2eeclient.SimpleContext.lookup(Ljavax/naming/Name;)Ljava/lang/Object;(SimpleContext.java:57)
at weblogic.j2eeclient.SimpleContext.lookup(Ljavax/naming/Name;)Ljava/lang/Object;(SimpleContext.java:57)
at weblogic.j2eeclient.SimpleContext.lookup(Ljava/lang/String;)Ljava/lang/Object;(SimpleContext.java:62)
at weblogic.jndi.factories.java.ReadOnlyContextWrapper.lookup(Ljava/lang/String;)Ljava/lang/Object;(ReadOnlyCont
extWrapper.java:45)
at weblogic.jndi.internal.AbstractURLContext.lookup(Ljava/lang/String;)Ljava/lang/Object;(AbstractURLContext.jav
a:130)
at javax.naming.InitialContext.lookup(Ljava/lang/String;)Ljava/lang/Object;(InitialContext.java:347)
at com.lb.equities.veda.tools.salesvault.jsp.ClientPageBean.initEJB()V(ClientPageBean.java:218)
at com.lb.equities.veda.tools.salesvault.jsp.ClientPageBean.readObject(Ljava/io/ObjectInputStream;)V(ClientPageB
ean.java:191)
at java.lang.LangAccessImpl.readObject(Ljava/lang/Class;Ljava/lang/Object;Ljava/io/ObjectInputStream;)V(Unknown
Source)
at java.io.ObjectStreamClass.invokeReadObject(Ljava/lang/Object;Ljava/io/ObjectInputStream;)V(Unknown Source)
at java.io.ObjectInputStream.readSerialData(Ljava/lang/Object;Ljava/io/ObjectStreamClass;)V(Unknown Source)
at java.io.ObjectInputStream.readOrdinaryObject(Z)Ljava/lang/Object;(Unknown Source)
at java.io.ObjectInputStream.readObject0(Z)Ljava/lang/Object;(Unknown Source)
at java.io.ObjectInputStream.readObject()Ljava/lang/Object;(Unknown Source)
at java.util.HashMap.readObject(Ljava/io/ObjectInputStream;)V(Unknown Source)
at java.lang.LangAccessImpl.readObject(Ljava/lang/Class;Ljava/lang/Object;Ljava/io/ObjectInputStream;)V(Unknown
Source)
at java.io.ObjectStreamClass.invokeReadObject(Ljava/lang/Object;Ljava/io/ObjectInputStream;)V(Unknown Source)
at java.io.ObjectInputStream.readSerialData(Ljava/lang/Object;Ljava/io/ObjectStreamClass;)V(Unknown Source)
at java.io.ObjectInputStream.readOrdinaryObject(Z)Ljava/lang/Object;(Unknown Source)
at java.io.ObjectInputStream.readObject0(Z)Ljava/lang/Object;(Unknown Source)
at java.io.ObjectInputStream.defaultReadFields(Ljava/lang/Object;Ljava/io/ObjectStreamClass;)V(Unknown Source)
at java.io.ObjectInputStream.readSerialData(Ljava/lang/Object;Ljava/io/ObjectStreamClass;)V(Unknown Source)
at java.io.ObjectInputStream.readOrdinaryObject(Z)Ljava/lang/Object;(Unknown Source)
at java.io.ObjectInputStream.readObject0(Z)Ljava/lang/Object;(Unknown Source)
at java.io.ObjectInputStream.readObject()Ljava/lang/Object;(Unknown Source)
at weblogic.common.internal.ChunkedObjectInputStream.readObject()Ljava/lang/Object;(ChunkedObjectInputStream.jav
a:120)
at weblogic.rjvm.MsgAbbrevInputStream.readObject(Ljava/lang/Class;)Ljava/lang/Object;(MsgAbbrevInputStream.java:
121)
at weblogic.cluster.replication.ReplicationManager_WLSkel.invoke(ILweblogic/rmi/spi/InboundRequest;Lweblogic/rmi
/spi/OutboundResponse;Ljava/lang/Object;)Lweblogic/rmi/spi/OutboundResponse;(Unknown Source)
at weblogic.rmi.internal.BasicServerRef.invoke(Lweblogic/rmi/extensions/server/RuntimeMethodDescriptor;Lweblogic
/rmi/spi/InboundRequest;Lweblogic/rmi/spi/OutboundResponse;)V(BasicServerRef.java:492)
Please help .
Thanks in Advance.
Edited by hforever at 03/04/2008 7:28 AM

JNDI lookup issue in weblogic 10 server

Hi all,
I have a serious problem in getting the datasource lookup. My application uses EJB3 and JPA and it is deployed in weblogic10. I configured datasource in the domain (ex:mydomain) using weblogic 10 admin console. Now when i try to call from a client program, it is giving me javax.naming.NameNotFoundException. I use eclipse IDE to deploy the application. From the IDE, i can start the oracle 10.3 server and it automatically deploys the application into the server in mydomain. The admin console shows that the application deployed fine. And i can see the webcontent WAR file and EJB jar deployed. Coming back to the issue.... I verified user_projects\domains\mydomain\config\jdbc\datasource-jdbc.xml and user_projects\domains\mydomain\config\config.xml file enteries. My entries are present in those files.
When i start the server i am getting below error...
<< Stacktrace >>
javax.naming.NameNotFoundException: While trying to look up jdbc in /app.; remaining name 'jdbc'
     at weblogic.jndi.internal.BasicNamingNode.newNameNotFoundException(BasicNamingNode.java:1139)
     at weblogic.jndi.internal.ApplicationNamingNode.lookup(ApplicationNamingNode.java:144)
     at weblogic.jndi.internal.WLEventContextImpl.lookup(WLEventContextImpl.java:254)
     at weblogic.jndi.internal.WLContextImpl.lookup(WLContextImpl.java:380)
     at weblogic.deployment.PersistenceUnitInfoImpl.lookUpAppScopedDataSource(PersistenceUnitInfoImpl.java:529)
     at weblogic.deployment.PersistenceUnitInfoImpl.reconfig(PersistenceUnitInfoImpl.java:549)
     at weblogic.ejb.container.deployer.EJBModule.reconfigPersistenceUnits(EJBModule.java:529)
     at weblogic.ejb.container.deployer.EJBModule.activate(EJBModule.java:515)
     at weblogic.application.internal.flow.ModuleListenerInvoker.activate(ModuleListenerInvoker.java:107)
     at weblogic.application.internal.flow.DeploymentCallbackFlow$2.next(DeploymentCallbackFlow.java:411)
     at weblogic.application.utils.StateMachineDriver.nextState(StateMachineDriver.java:37)
     at weblogic.application.internal.flow.DeploymentCallbackFlow.activate(DeploymentCallbackFlow.java:74)
     at weblogic.application.internal.flow.DeploymentCallbackFlow.activate(DeploymentCallbackFlow.java:66)
     at weblogic.application.internal.BaseDeployment$2.next(BaseDeployment.java:635)
     at weblogic.application.utils.StateMachineDriver.nextState(StateMachineDriver.java:37)
     at weblogic.application.internal.BaseDeployment.activate(BaseDeployment.java:212)
     at weblogic.application.internal.EarDeployment.activate(EarDeployment.java:16)
     at weblogic.application.internal.DeploymentStateChecker.activate(DeploymentStateChecker.java:162)
     at weblogic.deploy.internal.targetserver.AppContainerInvoker.activate(AppContainerInvoker.java:79)
     at weblogic.deploy.internal.targetserver.operations.AbstractOperation.activate(AbstractOperation.java:569)
     at weblogic.deploy.internal.targetserver.operations.ActivateOperation.activateDeployment(ActivateOperation.java:140)
     at weblogic.deploy.internal.targetserver.operations.ActivateOperation.doCommit(ActivateOperation.java:106)
     at weblogic.deploy.internal.targetserver.operations.AbstractOperation.commit(AbstractOperation.java:323)
     at weblogic.deploy.internal.targetserver.DeploymentManager.handleDeploymentCommit(DeploymentManager.java:820)
     at weblogic.deploy.internal.targetserver.DeploymentManager.activateDeploymentList(DeploymentManager.java:1227)
     at weblogic.deploy.internal.targetserver.DeploymentManager.handleCommit(DeploymentManager.java:436)
     at weblogic.deploy.internal.targetserver.DeploymentServiceDispatcher.commit(DeploymentServiceDispatcher.java:163)
     at weblogic.deploy.service.internal.targetserver.DeploymentReceiverCallbackDeliverer.doCommitCallback(DeploymentReceiverCallbackDeliverer.java:181)
     at weblogic.deploy.service.internal.targetserver.DeploymentReceiverCallbackDeliverer.access$100(DeploymentReceiverCallbackDeliverer.java:12)
     at weblogic.deploy.service.internal.targetserver.DeploymentReceiverCallbackDeliverer$2.run(DeploymentReceiverCallbackDeliverer.java:67)
     at weblogic.work.SelfTuningWorkManagerImpl$WorkAdapterImpl.run(SelfTuningWorkManagerImpl.java:516)
     at weblogic.work.ExecuteThread.execute(ExecuteThread.java:201)
     at weblogic.work.ExecuteThread.run(ExecuteThread.java:173)
<< Client program snippet >>
Hashtable ht = new Hashtable();
               ht.put(Context.INITIAL_CONTEXT_FACTORY,"weblogic.jndi.WLInitialContextFactory");
               ht.put(Context.PROVIDER_URL, "t3://10.237.76.132:7001");
               InitialContext ctx = null;
               ctx = new InitialContext(ht);
               Object obj = (Object)ctx.lookup(EmployeeBean.RemoteJNDIName);
               EmployeeRemote empRemote = (EmployeeRemote)PortableRemoteObject.narrow(obj,com.acs.test.emp.EmployeeRemote.class);
               List empList = empRemote.getEmployeeDetails(1);
               System.out.println("SUCCESS"+empList.size());
<< Persistence.xml >>
<?xml version="1.0" encoding="UTF-8"?>

<persistence xmlns="http://java.sun.com/xml/ns/persistence"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_1_0.xsd"
version="1.0">
<persistence-unit name="cmsepool">
<jta-data-source>java:/mydatasource</jta-data-source>
          <class>com.acs.test.emp.EmployeeVO</class>
          <properties>
<property name="hibernate.dialect" value="org.hibernate.dialect.HSQLDialect"/>
          <property name="hibernate.transaction.manager_lookup_class" value="org.hibernate.transaction.WeblogicTransactionManagerLookup"/>
</properties>
</persistence-unit>
</persistence>

Make sure that this Datasource you created is Targetted to Admin Server and full Cluster (incase of cluster domain). From Admin Console, select your datasource and check for the Targets tab. Since its JNDI lookup error, most probably it may not be deployed properly.
HTH
Ravi Jegga

JNDI lookup in Multitired clustered architecture

Hi alll,
We are in the design phase of a multi tired clustered application.
This application has jsp/servelet cluster and business application cluster. We are confused abt the JNDI lookup logic need to use in servlet cluster.
Can anyone help me to find out an optimal solution for jndi which gives the complete advantage of load balancing and esp. fail over
of clustering
Thanks in advance
gokul

Hi,
          First of all, I would like to clear the point that load balancing can be done within a cluster not among the cluster.
          So if you have more than one cluster the load balancing
          would be at each cluster level.
          For JNDI lookup you have to provide cluster address i.e combination of Managed Server Address e.g:
          t3://localhost:7001,localhost:8001,localhost:9001...etc
          Thanks,
          Qumar

Queue JNDI lookup in a clustered environment

Hey all,
          I know in a 6.1 cluster, the queues/JMS servers can only reside on one
          server.
          How can i lookup a queue from internal code from one of the off servers? The
          JNDI lookup doesn't grab it, throws an object not found exception. Do I need
          to
          be using the createQueue() method in the QueueSession class?
          It's fairly critical to know this to get our app up on the cluster, so
          any help would
          be very appreciated!
          Thanks,
          Greg


          A dumb question - how do I specify JNDINameReplicated=false? I am using WLS 6.1
          SP3 and in my config.xml I have
          <JMSTopic Name="topicA" JNDIName="topicA" JNDINameReplicated="false" />
          but WebLogic does not like it.
          Eric Ma
          Tom Barnes <[email protected]> wrote:
          >The parameter name "JNDINameReplicated" parameter is only available in
          >a patch
          >on top
          >of SP2 or SP3, and is "true" by default. I doubt that you are using
          >it.
          >
          >Greg Kaestle wrote:
          >
          >> Thanks much,
          >> Where is this parameter set in config.xml?
          >>
          >> Greg
          >>
          >> "Shean-Guang Chang" <[email protected]> wrote in message
          >> news:[email protected]...
          >> > If you want the queue to be found from other server in the same cluster
          >> then
          >> > you should not set "JNDINameReplicated" to false. This
          >> > will make the JNDI name of the queue known to the local server which
          >is
          >> > hosting the JMS queue. The purpose to use "JNDINameReplicated=false"
          >> > is to have multiple queues with the same JNDI name and then use some
          >sort
          >> of
          >> > load balancer to spread load among different JMS servers in the cluster.
          >> >
          >> >
          >> > "Greg Kaestle" <[email protected]> wrote in message
          >> > news:[email protected]...
          >> > > Hey all,
          >> > >
          >> > > I know in a 6.1 cluster, the queues/JMS servers can only reside
          >on
          >> one
          >> > > server.
          >> > > How can i lookup a queue from internal code from one of the off
          >servers?
          >> > The
          >> > > JNDI lookup doesn't grab it, throws an object not found exception.
          >Do I
          >> > need
          >> > > to
          >> > > be using the createQueue() method in the QueueSession class?
          >> > >
          >> > > It's fairly critical to know this to get our app up on the cluster,
          >> so
          >> > > any help would
          >> > > be very appreciated!
          >> > >
          >> > > Thanks,
          >> > > Greg
          >> > >
          >> > >
          >> >
          >> >
          >

EJB lookup in a cluster (DNS names to servers mapping)

          I am using weblogic6.0 to setup a object clusters. Currently I have 2 physical
          machine each running one object server.
          I have a servlet in the web tier (it is not part of the cluster) that lookups
          the EJB's.
          From the documentation, I understand intialContext lookup should use one DNS name
          that maps to both the object servers.
          My question is how can I setup that ?
          - I tried the following, I am not sure if this is right
          I created a virtualhost with
          name: MyVirtualHost
          virtual host names : MyCluster (this is name of the cluster I had setup )
          Targets : MyCluster
          I tried looking up with
          t3//MyVirtualHost:7001 and t3//MyCluster:7001
          No luck in both the cases !!!!!
          Note : I restarted my weblogic servers after
          creating the virtual host. But I did not reboot my machine ( don't know if this
          is required )
          Please help !!!!
          Thanks
          Abi -


          You need add an entry in Domain Name Server to include your host1 and host2, and
          use it in your JNDI lookup. Or you can do:
          t3://host1,host2:7001
          Both ways should work. Will load balancing to two JNDI trees.
          Jim Zhou.
          "Abinesh Puthenpurackal" <[email protected]> wrote:
          >
          >I am using weblogic6.0 to setup a object clusters. Currently I have 2
          >physical
          >machine each running one object server.
          >
          >I have a servlet in the web tier (it is not part of the cluster) that
          >lookups
          >the EJB's.
          >
          >From the documentation, I understand intialContext lookup should use
          >one DNS name
          >that maps to both the object servers.
          >
          >My question is how can I setup that ?
          > - I tried the following, I am not sure if this is right
          > I created a virtualhost with
          > name: MyVirtualHost
          > virtual host names : MyCluster (this is name of the cluster I had
          >setup )
          > Targets : MyCluster
          >
          >I tried looking up with
          >t3//MyVirtualHost:7001 and t3//MyCluster:7001
          >
          >No luck in both the cases !!!!!
          >
          >Note : I restarted my weblogic servers after
          >creating the virtual host. But I did not reboot my machine ( don't know
          >if this
          >is required )
          >
          >Please help !!!!
          >
          >Thanks
          >Abi -
          >

Weblogic JNDI lookup in Applet

Hi
We are facing problem in JNDI lookup inside the applet
here is the scenario
We have two weblogic servers(port 7001)
one server is main server where the Applet1 , weblogic.jar and app.htm
are in C:\bea\wlserver6.0sp1\config\mydomain\applications\DefaultWebApp_myserver
and another is proxy server where HTTPProxyServlet is running and one
web.xml file ( wall these files are provided by weblogic and the port
of proxy server is 448)
Both the servers are running on different machines
and when we run the client browser and put the folloing url
http://proxyServer IP Address:448/app.htm
we get the following exception
Java(TM) Plug-in: Version 1.3.0-C
Using JRE version 1.3.0 Java HotSpot(TM) Client VM
User home directory = C:\Documents and Settings\kkumar
Proxy Configuration: no proxy
JAR cache enabled.
In Init.1..:
In Init.after ..doClassLoaderWorkaround
In Init.after setText:
In Init.before initjms:
In initjms begin
In initjms hostName...:10.1.10.211
In initjms before initialcontext...:
In initjms after initialcontext...:
javax.naming.ConfigurationException. Root exception is
java.rmi.MarshalException: failed to marshal public abstract
java.lang.Object
weblogic.jndi.internal.NamingNode.lookup(java.lang.String,java.util.Hashtable)
throws javax.naming.NamingException,java.rmi.RemoteException; nested
exception is:
java.io.NotSerializableException: javax.naming.InitialContext
java.io.NotSerializableException: javax.naming.InitialContext
at java.io.ObjectOutputStream.outputObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject(Unknown Source)
at java.io.ObjectOutputStream.outputClassFields(Unknown Source)
at java.io.ObjectOutputStream.defaultWriteObject(Unknown Source)
at java.io.ObjectOutputStream.outputObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject(Unknown Source)
at java.util.Hashtable.writeObject(Unknown Source)
at java.lang.reflect.Method.invoke(Native Method)
at java.io.ObjectOutputStream.invokeObjectWriter(Unknown Source)
at java.io.ObjectOutputStream.outputObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject(Unknown Source)
at
weblogic.common.internal.ChunkedObjectOutputStream.writeObject(ChunkedObjectOutputStream.java:102)
at
weblogic.common.internal.ChunkedObjectOutputStream.writeObject(ChunkedObjectOutputStream.java:108)
at weblogic.rmi.internal.ObjectIO.writeObject(ObjectIO.java:19)
at
weblogic.rmi.internal.BasicRemoteRef.marshalArgs(BasicRemoteRef.java:121)
at
weblogic.rmi.cluster.ReplicaAwareRemoteRef.invoke(ReplicaAwareRemoteRef.java:246)
at
weblogic.rmi.cluster.ReplicaAwareRemoteRef.invoke(ReplicaAwareRemoteRef.java:225)
at
weblogic.jndi.internal.ServerNamingNode_WLStub.lookup(ServerNamingNode_WLStub.java:121)
at weblogic.jndi.internal.WLContextImpl.lookup(WLContextImpl.java:323)
at javax.naming.InitialContext.lookup(Unknown Source)
at Applet1.initJMS(Applet1.java:128)
at Applet1.init(Applet1.java:46)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Initialization failed
In Init.end of initjms:
the files are here
app.htm
               <OBJECT classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93"
                    width="650" height="300" align="baseline"
                    codebase="http://java.sun.com/products/plugin/1.2.2/jinstall-1_2_2-win.cab#Version=1,2,2,0"
>
               <PARAM NAME="code" VALUE="Applet1">
               <PARAM NAME="codebase" VALUE=".">
               <PARAM NAME="AppletName" VALUE="Applet1">
               <PARAM NAME="archive" VALUE="weblogic.jar">
               <PARAM NAME="MAYSCRIPT" VALUE="true">
               <PARAM NAME="type"
VALUE="application/x-java-applet;version=1.2.2">
               <PARAM NAME="model" VALUE="models/HyaluronicAcid.xyz">
               <PARAM NAME="scriptable" VALUE="true">
               
                              No JDK 1.2 support for APPLET!!
                    </NOEMBED>
                    </EMBED>
               </OBJECT>
</html>
Applet1.java
import java.awt.*;
import java.applet.*;
import java.net.*;
import java.util.*;
import javax.naming.*;
import javax.jms.*;
import java.lang.reflect.*;
public class Applet1 extends Applet implements MessageListener {
private boolean started = false;
// JMS Stuff
private InitialContext jmsContext = null;
private QueueConnectionFactory jmsConnFactory = null;
private QueueConnection jmsConnection = null;
private Queue jmsQueue = null;
private QueueSession jmsSession = null;
private QueueSender jmsSender = null;
private QueueReceiver jmsReceiver = null;
// init - called to inform this applet that it has been
// loaded into the system
public void init() {
//{{INIT_CONTROLS
System.out.println("In Init.1..:");
     //doClassLoaderWorkaround();
System.out.println("In Init.after ..doClassLoaderWorkaround");
setLayout(null);
setSize(426,266);
jmslabel.setText("JMS Applet");
System.out.println("In Init.after setText:");
add(jmslabel);
jmslabel.setBounds(144,12,148,24);
textArea1.setEnabled(false);
add(textArea1);
textArea1.setBounds(24,36,375,100);
jmsleaveButton.setLabel("Leave");
add(jmsleaveButton);
jmsleaveButton.setBackground(java.awt.Color.lightGray);
jmsleaveButton.setBounds(312,240,78,20);
add(jmsMessageField);
jmsMessageField.setBounds(24,168,367,38);
System.out.println("In Init.before initjms:");
initJMS();
System.out.println("In Init.end of initjms:");
//{{DECLARE_CONTROLS
     java.awt.Label jmslabel = new java.awt.Label();
     java.awt.TextArea textArea1 = new java.awt.TextArea();
     java.awt.Button jmsleaveButton = new java.awt.Button();
     java.awt.TextField jmsMessageField = new java.awt.TextField();
// getAppletInfo - Returns information about this applet.
public String getAppletInfo() {
return "JMS Applet\r\n";
// destroy - called to inform this applet that it is being
// reclaimed and that it should destroy any resources that
// it has allocated.
public void destroy() {
try {
if(started) {
if (jmsConnection != null) {
jmsConnection.stop();
jmsConnection = null;
started = false;
stop();
catch(Exception e) {
// start - called to inform this applet that it should start its
execution
public void start() {
if(!started) {
started = true;
// stop - Called to inform this applet that it should stop its
execution
public void stop() {
textArea1.setEnabled(false);
jmsMessageField.setEnabled(false);
// action - handles entering message, Leave button clicked
public boolean action(Event evt, Object obj) {
System.out.println("In action begin:");
if(evt.id == Event.ACTION_EVENT) {
if(obj.equals(jmsMessageField.getText())) {
System.out.println("In action before sendData:");
sendData(jmsMessageField.getText());
System.out.println("In action after sendData:");
jmsMessageField.setText("");
return true;
if(obj.equals(jmsleaveButton.getLabel())) {
destroy();
return true;
// initJMS - initialize all of the JMS stuff
private void initJMS() {
try {
System.out.println("In initjms begin");
String hostName = this.getCodeBase().getHost();
System.out.println("In initjms hostName...:"+hostName);
Hashtable env = new Hashtable();
env.put(Context.APPLET,this);
env.put(Context.PROVIDER_URL,
"t3://" + hostName + ":448");
env.put(Context.INITIAL_CONTEXT_FACTORY,
"weblogic.jndi.WLInitialContextFactory");
System.out.println("In initjms before initialcontext...:");
jmsContext = new InitialContext(env);
System.out.println("In initjms after initialcontext...:");
jmsConnFactory
=(QueueConnectionFactory)jmsContext.lookup("javax.jms.QueueConnectionFactory");
System.out.println("In initjms after initialcontext..lookup.:");
jmsConnection = jmsConnFactory.createQueueConnection();
System.out.println("In initjms after initialcontext..lookup1.:");
jmsSession = jmsConnection.createQueueSession(false,Session.AUTO_ACKNOWLEDGE);
System.out.println("In initjms before lookup...:");
jmsQueue =(Queue)jmsContext.lookup("jms.queue.TestQueue1");
jmsConnection.start();
jmsSender = jmsSession.createSender(jmsQueue);
jmsReceiver = jmsSession.createReceiver(jmsQueue);
jmsReceiver.setMessageListener(this);
System.out.println("In initjms before setMessageListener...end of the
const:");
catch(Exception e) {
e.printStackTrace();
System.out.println("Initialization failed");
// sendData - sends a message
void sendData(String data) {
try {
System.out.println("In sendData before createTextMessage:");
TextMessage message = jmsSession.createTextMessage();
message.setText(data);
jmsSender.send(message);
System.out.println("In sendData end data:"+data);
catch(Exception e) {
System.out.println("Failed to send message");
// onMessage - asynchronously receives a message
public void onMessage(Message message) {
String data;
try {
System.out.println("In onMessage:");
data = ((TextMessage)message).getText();
System.out.println("In onMessage data:"+data);
textArea1.append(data + "\n");
repaint();
System.out.println("In onMessage end:");
catch(Exception e) {
System.out.println("Failed to receive message");
private void doClassLoaderWorkaround(){
boolean didit = false;
// Get the ClassLoader of this applet:
ClassLoader cloader = this.getClass().getClassLoader();
if (cloader == null){
System.out.println("### getClassLoader() returned null");
else
// We might call this handy utility routine:
// boolean didit =
Thread.currentThread().setContextClassLoader(cloader);
     Method setContextClassLoaderMeth = null;
     try {
          Method [] allMethods = Thread.class.getMethods();
          for ( int i = 0; i < allMethods.length; i++ ) {
               if (allMethods.getName().equals("setContextClassLoader")) {
                    setContextClassLoaderMeth = allMethods[i];
                    break;
     catch(Exception e) {
          System.out.println("---Exception " + e);
// but we don't because we need more visibility about what goes
wrong.
// Rather, reproduce that logic here, with extra error messages:
//Method setContextClassLoaderMeth = null;
try{
// Class params = ClassLoader.class ;
// setContextClassLoaderMeth =
//Thread.class.getMethod("setContextClassLoader", params);
catch (NoSuchMethodException ne) {
setContextClassLoaderMeth = null;
System.out.println("--- This java version does not have the
method 'setContextClassLoader'. Not a problem.");
return;
catch (Exception ae){
setContextClassLoaderMeth = null;
System.out.println("### Thread.class.getMethod() threw
unexpected exception: " + ae.getMessage());
if (setContextClassLoaderMeth != null){
Object[] args = { cloader };
try{
setContextClassLoaderMeth.invoke(Thread.currentThread(),
args);
didit = true;
catch (InvocationTargetException ite){
Throwable be = ite.getTargetException();
System.out.println("### Thread.setContextClassLoader() failed:
InvocationTargetException: " + be.getMessage());
catch (Exception ie){
System.out.println("### Thread.setContextClassLoader() threw
unexpected exception: " + ie.getMessage());
if (didit){
System.out.println("--- Succeeded in setting the
ContextClassLoader of this thread to be this applet's own
ClassLoader");
else{
System.out.println("### Could not set ContextClassLoader,
additional threads may not be able");
System.out.println("### to get a JNDI Context in java 122 or
greater.");
any clue or thought. please help
regards
mohan

It looks like the object that you have placed into the JNDO tree is not serializable or doesnt implement exernalizable!
java.io.NotSerializableException
0rrc
On 26 Jul 2001 16:10:35 -0700, [email protected] (Mohan Raj) wrote:
Hi
We are facing problem in JNDI lookup inside the applet
here is the scenario
We have two weblogic servers(port 7001)
one server is main server where the Applet1 , weblogic.jar and app.htm
are in C:\bea\wlserver6.0sp1\config\mydomain\applications\DefaultWebApp_myserver
and another is proxy server where HTTPProxyServlet is running and one
web.xml file ( wall these files are provided by weblogic and the port
of proxy server is 448)
Both the servers are running on different machines
and when we run the client browser and put the folloing url
http://proxyServer IP Address:448/app.htm
we get the following exception
Java(TM) Plug-in: Version 1.3.0-C
Using JRE version 1.3.0 Java HotSpot(TM) Client VM
User home directory = C:\Documents and Settings\kkumar
Proxy Configuration: no proxy
JAR cache enabled.
In Init.1..:
In Init.after ..doClassLoaderWorkaround
In Init.after setText:
In Init.before initjms:
In initjms begin
In initjms hostName...:10.1.10.211
In initjms before initialcontext...:
In initjms after initialcontext...:
javax.naming.ConfigurationException. Root exception is
java.rmi.MarshalException: failed to marshal public abstract
java.lang.Object
weblogic.jndi.internal.NamingNode.lookup(java.lang.String,java.util.Hashtable)
throws javax.naming.NamingException,java.rmi.RemoteException; nested
exception is:
java.io.NotSerializableException: javax.naming.InitialContext
java.io.NotSerializableException: javax.naming.InitialContext
at java.io.ObjectOutputStream.outputObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject(Unknown Source)
at java.io.ObjectOutputStream.outputClassFields(Unknown Source)
at java.io.ObjectOutputStream.defaultWriteObject(Unknown Source)
at java.io.ObjectOutputStream.outputObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject(Unknown Source)
at java.util.Hashtable.writeObject(Unknown Source)
at java.lang.reflect.Method.invoke(Native Method)
at java.io.ObjectOutputStream.invokeObjectWriter(Unknown Source)
at java.io.ObjectOutputStream.outputObject(Unknown Source)
at java.io.ObjectOutputStream.writeObject(Unknown Source)
at
weblogic.common.internal.ChunkedObjectOutputStream.writeObject(ChunkedObjectOutputStream.java:102)
at
weblogic.common.internal.ChunkedObjectOutputStream.writeObject(ChunkedObjectOutputStream.java:108)
at weblogic.rmi.internal.ObjectIO.writeObject(ObjectIO.java:19)
at
weblogic.rmi.internal.BasicRemoteRef.marshalArgs(BasicRemoteRef.java:121)
at
weblogic.rmi.cluster.ReplicaAwareRemoteRef.invoke(ReplicaAwareRemoteRef.java:246)
at
weblogic.rmi.cluster.ReplicaAwareRemoteRef.invoke(ReplicaAwareRemoteRef.java:225)
at
weblogic.jndi.internal.ServerNamingNode_WLStub.lookup(ServerNamingNode_WLStub.java:121)
at weblogic.jndi.internal.WLContextImpl.lookup(WLContextImpl.java:323)
at javax.naming.InitialContext.lookup(Unknown Source)
at Applet1.initJMS(Applet1.java:128)
at Applet1.init(Applet1.java:46)
at sun.applet.AppletPanel.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Initialization failed
In Init.end of initjms:
the files are here
app.htm
               <OBJECT classid="clsid:8AD9C840-044E-11D1-B3E9-00805F499D93"
                    width="650" height="300" align="baseline"
                    codebase="http://java.sun.com/products/plugin/1.2.2/jinstall-1_2_2-win.cab#Version=1,2,2,0"
>
               <PARAM NAME="code" VALUE="Applet1">
               <PARAM NAME="codebase" VALUE=".">
               <PARAM NAME="AppletName" VALUE="Applet1">
               <PARAM NAME="archive" VALUE="weblogic.jar">
               <PARAM NAME="MAYSCRIPT" VALUE="true">
               <PARAM NAME="type"
VALUE="application/x-java-applet;version=1.2.2">
               <PARAM NAME="model" VALUE="models/HyaluronicAcid.xyz">
               <PARAM NAME="scriptable" VALUE="true">
               
                              No JDK 1.2 support for APPLET!!
                    </NOEMBED>
                    </EMBED>
               </OBJECT>
</html>
Applet1.java
import java.awt.*;
import java.applet.*;
import java.net.*;
import java.util.*;
import javax.naming.*;
import javax.jms.*;
import java.lang.reflect.*;
public class Applet1 extends Applet implements MessageListener {
private boolean started = false;
// JMS Stuff
private InitialContext jmsContext = null;
private QueueConnectionFactory jmsConnFactory = null;
private QueueConnection jmsConnection = null;
private Queue jmsQueue = null;
private QueueSession jmsSession = null;
private QueueSender jmsSender = null;
private QueueReceiver jmsReceiver = null;
// init - called to inform this applet that it has been
// loaded into the system
public void init() {
//{{INIT_CONTROLS
System.out.println("In Init.1..:");
     //doClassLoaderWorkaround();
System.out.println("In Init.after ..doClassLoaderWorkaround");
setLayout(null);
setSize(426,266);
jmslabel.setText("JMS Applet");
System.out.println("In Init.after setText:");
add(jmslabel);
jmslabel.setBounds(144,12,148,24);
textArea1.setEnabled(false);
add(textArea1);
textArea1.setBounds(24,36,375,100);
jmsleaveButton.setLabel("Leave");
add(jmsleaveButton);
jmsleaveButton.setBackground(java.awt.Color.lightGray);
jmsleaveButton.setBounds(312,240,78,20);
add(jmsMessageField);
jmsMessageField.setBounds(24,168,367,38);
System.out.println("In Init.before initjms:");
initJMS();
System.out.println("In Init.end of initjms:");
//{{DECLARE_CONTROLS
     java.awt.Label jmslabel = new java.awt.Label();
     java.awt.TextArea textArea1 = new java.awt.TextArea();
     java.awt.Button jmsleaveButton = new java.awt.Button();
     java.awt.TextField jmsMessageField = new java.awt.TextField();
// getAppletInfo - Returns information about this applet.
public String getAppletInfo() {
return "JMS Applet\r\n";
// destroy - called to inform this applet that it is being
// reclaimed and that it should destroy any resources that
// it has allocated.
public void destroy() {
try {
if(started) {
if (jmsConnection != null) {
jmsConnection.stop();
jmsConnection = null;
started = false;
stop();
catch(Exception e) {
// start - called to inform this applet that it should start its
execution
public void start() {
if(!started) {
started = true;
// stop - Called to inform this applet that it should stop its
execution
public void stop() {
textArea1.setEnabled(false);
jmsMessageField.setEnabled(false);
// action - handles entering message, Leave button clicked
public boolean action(Event evt, Object obj) {
System.out.println("In action begin:");
if(evt.id == Event.ACTION_EVENT) {
if(obj.equals(jmsMessageField.getText())) {
System.out.println("In action before sendData:");
sendData(jmsMessageField.getText());
System.out.println("In action after sendData:");
jmsMessageField.setText("");
return true;
if(obj.equals(jmsleaveButton.getLabel())) {
destroy();
return true;
// initJMS - initialize all of the JMS stuff
private void initJMS() {
try {
System.out.println("In initjms begin");
String hostName = this.getCodeBase().getHost();
System.out.println("In initjms hostName...:"+hostName);
Hashtable env = new Hashtable();
env.put(Context.APPLET,this);
env.put(Context.PROVIDER_URL,
"t3://" + hostName + ":448");
env.put(Context.INITIAL_CONTEXT_FACTORY,
"weblogic.jndi.WLInitialContextFactory");
System.out.println("In initjms before initialcontext...:");
jmsContext = new InitialContext(env);
System.out.println("In initjms after initialcontext...:");
jmsConnFactory
=(QueueConnectionFactory)jmsContext.lookup("javax.jms.QueueConnectionFactory");
System.out.println("In initjms after initialcontext..lookup.:");
jmsConnection = jmsConnFactory.createQueueConnection();
System.out.println("In initjms after initialcontext..lookup1.:");
jmsSession = jmsConnection.createQueueSession(false,Session.AUTO_ACKNOWLEDGE);
System.out.println("In initjms before lookup...:");
jmsQueue =(Queue)jmsContext.lookup("jms.queue.TestQueue1");
jmsConnection.start();
jmsSender = jmsSession.createSender(jmsQueue);
jmsReceiver = jmsSession.createReceiver(jmsQueue);
jmsReceiver.setMessageListener(this);
System.out.println("In initjms before setMessageListener...end of the
const:");
catch(Exception e) {
e.printStackTrace();
System.out.println("Initialization failed");
// sendData - sends a message
void sendData(String data) {
try {
System.out.println("In sendData before createTextMessage:");
TextMessage message = jmsSession.createTextMessage();
message.setText(data);
jmsSender.send(message);
System.out.println("In sendData end data:"+data);
catch(Exception e) {
System.out.println("Failed to send message");
// onMessage - asynchronously receives a message
public void onMessage(Message message) {
String data;
try {
System.out.println("In onMessage:");
data = ((TextMessage)message).getText();
System.out.println("In onMessage data:"+data);
textArea1.append(data + "\n");
repaint();
System.out.println("In onMessage end:");
catch(Exception e) {
System.out.println("Failed to receive message");
private void doClassLoaderWorkaround(){
boolean didit = false;
// Get the ClassLoader of this applet:
ClassLoader cloader = this.getClass().getClassLoader();
if (cloader == null){
System.out.println("### getClassLoader() returned null");
else
// We might call this handy utility routine:
// boolean didit =
Thread.currentThread().setContextClassLoader(cloader);
     Method setContextClassLoaderMeth = null;
     try {
          Method [] allMethods = Thread.class.getMethods();
          for ( int i = 0; i < allMethods.length; i++ ) {
               if (allMethods.getName().equals("setContextClassLoader")) {
                    setContextClassLoaderMeth = allMethods[i];
                    break;
     catch(Exception e) {
          System.out.println("---Exception " + e);
// but we don't because we need more visibility about what goes
wrong.
// Rather, reproduce that logic here, with extra error messages:
//Method setContextClassLoaderMeth = null;
try{
// Class params = ClassLoader.class ;
// setContextClassLoaderMeth =
//Thread.class.getMethod("setContextClassLoader", params);
catch (NoSuchMethodException ne) {
setContextClassLoaderMeth = null;
System.out.println("--- This java version does not have the
method 'setContextClassLoader'. Not a problem.");
return;
catch (Exception ae){
setContextClassLoaderMeth = null;
System.out.println("### Thread.class.getMethod() threw
unexpected exception: " + ae.getMessage());
if (setContextClassLoaderMeth != null){
Object[] args = { cloader };
try{
setContextClassLoaderMeth.invoke(Thread.currentThread(),
args);
didit = true;
catch (InvocationTargetException ite){
Throwable be = ite.getTargetException();
System.out.println("### Thread.setContextClassLoader() failed:
InvocationTargetException: " + be.getMessage());
catch (Exception ie){
System.out.println("### Thread.setContextClassLoader() threw
unexpected exception: " + ie.getMessage());
if (didit){
System.out.println("--- Succeeded in setting the
ContextClassLoader of this thread to be this applet's own
ClassLoader");
else{
System.out.println("### Could not set ContextClassLoader,
additional threads may not be able");
System.out.println("### to get a JNDI Context in java 122 or
greater.");
any clue or thought. please help
regards
mohan

JNDI lookup using a proxy server

Hi,
I'm trying to use a weblogic server as a proxy server for a cluster of
weblogic servers. The static and dynamic content delivery works fine but
when I try to do a JNDI lookup from an applet client, I get a name not
resolved exception. I guess, it happens because the proxy server tries to
resolve the name from it's JNDI tree, whereas I expect it to forward this
request to one of the servers in the cluster. Is this possible? If it is, do
I need to set up some parameters in the proxy server? If not, can I do this
myself by writing a name resolution class which in turn will forward the
request to one of the servers in the cluster?
Any help would be greatly appreciated.
thanks
- sanjay

when u say "cluster of weblogic servers"..u mean the weblogic`s inbuilt
cluster..
the reason i ask is weblogic`s cluster do provide JNDI clustering too by using
cluster-wide naming tree..
Sanjay Aggarwal wrote:
Hi,
I'm trying to use a weblogic server as a proxy server for a cluster of
weblogic servers. The static and dynamic content delivery works fine but
when I try to do a JNDI lookup from an applet client, I get a name not
resolved exception. I guess, it happens because the proxy server tries to
resolve the name from it's JNDI tree, whereas I expect it to forward this
request to one of the servers in the cluster. Is this possible? If it is, do
I need to set up some parameters in the proxy server? If not, can I do this
myself by writing a name resolution class which in turn will forward the
request to one of the servers in the cluster?
Any help would be greatly appreciated.
thanks
- sanjay

Distributed Queue/JMX - JNDI lookup on startup fails

Hi,
I have a problem starting up Camel routes on a cluster via JMX. Although I have a NotificationListener registered that tries to startup the routes when the server sends a STATE=RUNNING lifecycle event, I cannot start the all Camel routes due to a "JMSException, Destination not found".
But, when I remote debug the application and put a breakpoint in, wait let's say 5 secs, then the JNDI lookup works and everything is fine.
I have unsuccessfully tried to play with the deployment order or my ear (by default the JMSServer is started with a priority of 1000), no luck. I have also put a poll method in, that waits until the JMSServer and the Destinations (=queues) are available, again no luck.
Anyone able to assist with that issue?
Best Regards,
Sebastian

I found the reason for the late binding. We are using "migratable target" in our cluster. When I remove the migratable target I have no issue whatsoever. Is there a way to either tweak the config or configure the Migratable targets in a way to by-pass this issue?
Regards,
Seb

WLPI: business operations JNDI lookup & service pack

Hello,
I ran into a problem attempting to define a business operation in the Studio application
using WLPI 1.2.1 (without service pack 1). Everything works up to the point where
I press the Done button and Studio attempts to create a new business operation
object. I am getting a JNDI lookup exception. It appearsejb-name of method in
isolation-level must be the same name as that of the weblogic-enterprise-bean
Studio is looking up the name 'com.bea.wlpi.businessoperation' while the business
operation bean is bound under 'com.bea.wlpi.BusinessOperation'.
In an attempt to fix this problem I upgraded to service pack 1, but am now unable
to deploy wlpi-ejb.jar because of the following error: "ejb-name of method in
isolation-level must be the same name as that of the weblogic-enterprise-bean".
Can anyone help me create a business operation?
Thanks,
Martin

Make sure that this Datasource you created is Targetted to Admin Server and full Cluster (incase of cluster domain). From Admin Console, select your datasource and check for the Targets tab. Since its JNDI lookup error, most probably it may not be deployed properly.
HTH
Ravi Jegga

WLS/OSB DB Adapter - JNDI lookup failed

Hello all.
I've got a DB adapter service set up in a clustered environment, and it all works (and I've built proxy services, transformations etc around it), but I've just noticed that the log shows a warning regarding the JNDI lookup of the ConnectionFactory, as below.
It's working, and the error is only a warning, but could this cause problems going forward, particularly with regards performance?
Given that the ConnectionFactory name is 'com.whatever.myServiceDB', and the Endpoint URI of the service is 'jca://com.whatever.myServiceDB', what could be wrong? Has anyone seen/fixed this before? It's almost like the managed servers don't know about the JNDI name...but the DbAdapter deployent has 'All servers in the cluster' selected in its 'Targets' tab, so I'm not sure.
Any pointers would be appreciated, I'm probably missing something obvious.
Cheers.
####<Apr 15, 2010 10:53:10 AM BST> <Warning> <JCA_FRAMEWORK_AND_ADAPTER> <servername> <managed3_domainname> <[ACTIVE] ExecuteThread: '4' for queue: 'weblogic.kernel.Default (self-tuning)'> <<anonymous>> <> <> <1271325190453> <BEA-000000> <servicebus:/WSDL/MyProject/MyService [ MyService_ptt::merge(MessagesCollection) ] - JNDI lookup of 'com.whatever.myServiceDB' failed due to: String index out of range: -1>

Thanks again.
In case anyone runs into a similar problem and is wondering: a bit of mucking about reveals that the WLS ConnectionFactory config is fine with dots or slashes, and it seems to treat both the same when creating the JNDI tree.
However, the WSDL (that you probably created in JDeveloper) has to have slashes for doing its lookup. So, for example, always use slashes rather than dots when setting your DB Adapter JNDI name in JDeveloper. I guess this is a bit different from usual class/package naming standards, so may catch someone else out too.
Cheers.

Is JNDI lookup efficient?

Two questions, please help. Thanks
1) Each node in a cluster has its own JNDI Tree?
2) How efficient is JNDI lookup?
Shiye Qiu
[email protected]

Yes, each node has its own copy of the JNDI tree.
JNDI lookups are fairly efficient, but it's still reasonable practice to cache the lookups. People typically have write a separate Service locator that handles this for their app.
-- Rob
WLS Blog http://dev2dev.bea.com/blog/rwoollen/

JNDI lookup keeps retrying

I am running a WLS6.1 SP4 cluster.
We don't have a hardware load-balancer so I put code in
to instantiate the InitialContext:
i.e. ctx = new InitialContext(props);
I put this in a try block so that I could trap the exception
when it fails to connect (then try the next URL in the list).
The problem is that the exception doesn't
get propogated back when using WLInitialContextFactory, it just keeps
retrying (and generating a bunch of exception logs in the weblogic log).
Is there anyway to alter the behaviour so that it doesn't keep
trying, but just raises an exception on instantiation failure, I
couldn't find a property that would let me alter the behaviour.
I realise that as the default behaviour, it makes perfect sense
to retry, but would just like to know if it is possible to
stop it.
thanks
Mike Carrington.

Is JNDI lookup costly that we need to cache the home
objects?usually yes; it is better to cache the (ejb) home objects in most of the cases.

JNDI lookup in a cluster

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