EJB 3.0 lookup in Weblogic 10.3.0

Question

Hello everyone,
1: Our application runs on Weblogic Application Server,version 10.3.0
2: In our system,we need to deploy an EJB conforming to the EJB 3.0 specification.
Please find the sample code for our UAT environment as below :
/*The remote interface*/
package com.serverside.ejb.session;
import javax.ejb.Remote;
@Remote
public interface ASimpleSessionBeanRemote {
     public void printThis(String print);
/*The bean class*/
package com.serverside.ejb.session;
import javax.ejb.Remote;
import javax.ejb.Stateless;
* Session Bean implementation class ASimpleSessionBean
@Stateless(name="ASimpleSessionBean", mappedName = "ASimpleSessionEJB")
@Remote(ASimpleSessionBeanRemote.class)
public class ASimpleSessionBean implements ASimpleSessionBeanRemote {
* Default constructor.
public ASimpleSessionBean() {
// TODO Auto-generated constructor stub
     @Override
     public void printThis(String print) {
          // TODO Auto-generated method stub
          System.out.println("ASimpleSessionBean : "+print);
3: The above files when packaged in jar get deployed on the server successfully.
4: As per EJB 3.0 specification,the deployement descriptors are not mandatory.Hence,the jar doesn't include ejb-jar.xml and weblogic-ejb-jar.xml
5: Please find below,the EJB3.0 annotations reference as per the Weblogic Application Server Documentation :
Annotation : @Stateless
Package: javax.ejb.Stateless
Attribute : mappedName
Description :
Specifies the product-specific name to which the stateless session bean should be mapped.
You can also use this attribute to specify the JNDI name of this stateless session bean. WebLogic Server uses the value of the mappedName attribute when creating the bean’s global JNDI name. In particular, the JNDI name will be:
mappedName#name_of_businessInterface
where name_of_businessInterface is the fully qualified name of the business interface of this session bean.
For example, if you specify mappedName="bank" and the fully qualified name of the business interface is com.CheckingAccount, then the JNDI of the business interface is bank#com.CheckingAccount.
6: Conforming to the above specification, the sample EJB deployed on our application server has the binding name(as reflected in the jndi tree) as follows :
ASimpleSessionEJB#com.serverside.ejb.session.ASimpleSessionBeanRemote
A jndi lookup using this name succeeds :
InitialContext.doLookup("ASimpleSessionEJB#com.serverside.ejb.session.ASimpleSesionBeanRemote");
7: Now,we want the binding name to be a simple string i.e the lookup must be something like :
InitialContext.doLookup("ASimpleSessionEJB");
8: To implement point-7,we tried using the ejb-jar.xml and weblogic-ejb-jar.xml as follows :
->ejb-jar.xml
<?xml version="1.0" encoding="ASCII"?>
<ejb-jar xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:ejb="http://java.sun.com/xml/ns/javaee/ejb-jar_3_0.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/ejb-jar_3_0.xsd" version="3.0">
<display-name>ejb</display-name>
<enterprise-beans>
     <session>
          <ejb-name>ASimpleSessionBean</ejb-name>
          <ejb-ref>
               <ejb-ref-name>ASimpleSessionEJB</ejb-ref-name>
               <remote>com.serverside.ejb.session.ASimpleSessionBeanRemote</remote>
               <mapped-name>ASimpleSessionEJB</mapped-name>
          </ejb-ref>
     </session>
</enterprise-beans>
</ejb-jar>
->weblogic-ejb-jar.xml
<?xml version="1.0" encoding="UTF-8"?>
<wls:weblogic-ejb-jar xmlns:wls="http://www.bea.com/ns/weblogic/weblogic-ejb-jar" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/ejb-jar_3_0.xsd http://www.bea.com/ns/weblogic/weblogic-ejb-jar http://www.bea.com/ns/weblogic/weblogic-ejb-jar/1.0/weblogic-ejb-jar.xsd">
<!-- server-version: 10.3.0 --><wls:weblogic-enterprise-bean>
     <wls:ejb-name>ASimpleSessionBean</wls:ejb-name>
     <wls:stateless-session-descriptor>
          <wls:business-interface-jndi-name-map>
               <wls:business-remote>ASimpleSessionBeanRemote</wls:business-remote>
               <wls:jndi-name>ASimpleSessionEJB</wls:jndi-name>
          </wls:business-interface-jndi-name-map></wls:stateless-session-descriptor>
     <wls:jndi-name>ASimpleSessionEJB</wls:jndi-name>
</wls:weblogic-enterprise-bean>
</wls:weblogic-ejb-jar>
9: Inspite of the point-8,the binding name remains as follows :
ASimpleSessionEJB#com.serverside.ejb.session.ASimpleSessionBeanRemote
10: Please guide us about the solution and implementation to attend point-7.
Thanks !

Answer 1

Hi,
I find distributed applications very interesting (even though this application of mine could just use sockets - it is nicer than EJB 2.1). You don't need the @Local DI and local interface if you only do remote - so here is some minimal hello world code that currently works on a test network of mine.
In this example I have provided only a remote stateless session bean and an SE client (could be a pojo or servlet).
The *@Stateful* SB has been converted to a *@Stateless* SB (now the state field doesn't really hold state as the container pools the SSB - but this is an unrelated issue as I an not using transactions yet anyway). The key is naming the SSB with the mappedName attribute so you can easily reference it - or just check your logs after you deploy the EAR containing the EJB in your EE server.
Note: WebLogic also registers a legacy EJB 2.1 compliant jndi name alias for you as well appsdirorg_eclipse_persistence_example_distributed_ClientEAR_earorg_eclipse_persistence_example_distributed_ClientEJB_jarNode_Home*
For your specific question about dependency injection (which is implemented by Spring AOP inside the server).
Use @Remote on your Remote inteface class
Use @Stateless on your session bean implementation class
Use @EJB to inject your stateless session bean into a servlet for example (I have not tried using @EJB on a POJO - it would need to be running on the WebLogic container in the WAR or EJB.jar - don't think that is supported - I have not tried @Resource or spring annotations for this yet)
This example (reduced to show a single remote server) uses a JNDI lookup to get a reference to the remote bean (full try/catch exception handlers in full code near end of post).
      Hashtable<String, String> aTable =  new Hashtable<String, String>();
      aTable.put("java.naming.factory.initial","weblogic.jndi.WLInitialContextFactory");
      aTable.put("java.naming.provider.url", "beowulf5");
      Context aContext = new InitialContext(aTable);
      Object aRemoteReference = aContext.lookup("ejb/Node#org.eclipse.persistence.example.distributed.NodeRemote");       
      NodeRemote aNode = (NodeRemote) PortableRemoteObject.narrow(aRemoteReference, NodeRemote.class);
      aNode.setState(0)); // remote method invocationI deploy an EAR containing the SSB on distributed servers on any EE container - I chose WebLogic 10.3.4.
I run an SE app that connects to a list of servers that that are running the remote stateless session bean. The code is very naive at this point, it does retry bad connections and it is not yet multithreaded - just a proof of concept for EJB 3 remote session beans.
The InitialContext RMI handshaking will take around 10 sec per server to setup - then you can do up to 200k remote EJB RMI invokacations per second/thread on my machine.
The @Local code is only required if you wish to optimize using your SSB on the same JVM.
The JPA peristence code can be ignored (no EJB 3.0 Entities)
I just discovered the forum code tag in square brackets after 2 years
package org.eclipse.persistence.example.distributed;
import javax.ejb.Remote;
@Remote
public interface NodeRemote {
    public void setState(int state);
    public int getState();
package org.eclipse.persistence.example.distributed;
import javax.ejb.Stateful;
@Stateful(mappedName="ejb/Node")
public class Node implements NodeRemote {
    private int state;
    public void setState(int aState) {        state = aState;    }
    public int getState() {        return state;    }
}weblogic-ejb-jar.xml ejb deployment descriptor - empty (we are using dependency injection annotations)
<?xml version="1.0" encoding="UTF-8"?>
<wls:weblogic-ejb-jar xmlns:wls="http://xmlns.oracle.com/weblogic/weblogic-ejb-jar" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/ejb-jar_3_0.xsd http://xmlns.oracle.com/weblogic/weblogic-ejb-jar http://xmlns.oracle.com/weblogic/weblogic-ejb-jar/1.2/weblogic-ejb-jar.xsd">
    <!--weblogic-version:10.3.4-->
</wls:weblogic-ejb-jar>weblogic-application.xml deployment descriptor - essentially empty
<?xml version="1.0" encoding="UTF-8"?>
<wls:weblogic-application xmlns:wls="http://xmlns.oracle.com/weblogic/weblogic-application" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/javaee_5.xsd http://xmlns.oracle.com/weblogic/weblogic-application http://xmlns.oracle.com/weblogic/weblogic-application/1.2/weblogic-application.xsd">
    <!--weblogic-version:10.3.4-->
    <wls:application-param>
        <wls:param-name>webapp.encoding.default</wls:param-name>
        <wls:param-value>UTF-8</wls:param-value>
    </wls:application-param>
</wls:weblogic-application>application.xml JEE5 deployment descriptor - you can ignore the model.jar and war
<?xml version="1.0" encoding="UTF-8"?>
<application xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:application="http://java.sun.com/xml/ns/javaee/application_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/application_5.xsd" id="Application_ID" version="5">
  <display-name>
org.eclipse.persistence.example.distributed.ClientEAR</display-name>
  <module>
    <java>org.eclipse.persistence.example.distributed.Model.jar</java>
  </module>
  <module>
    <web>
      <web-uri>org.eclipse.persistence.example.distributed.ClientWeb.war</web-uri>
      <context-root>distributed</context-root>
    </web>
  </module>
  <module>
    <ejb>org.eclipse.persistence.example.distributed.ClientEJB.jar</ejb>
  </module>
</application>SE java client code (run from Eclipse 3.6 EE edition)
package org.eclipse.persistence.example.distributed;
import java.rmi.ConnectException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Hashtable;
import java.util.List;
import java.util.Map;
import javax.ejb.EJBException;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.rmi.PortableRemoteObject;
import org.eclipse.persistence.example.distributed.NodeRemote;
import org.eclipse.persistence.example.distributed.network.Cell;
import org.eclipse.persistence.example.distributed.network.Quad;
import org.eclipse.persistence.example.distributed.network.Wire;
* This class tests RMI connections to multiple WebLogic servers running on
* remote JVM's.  It is intended for experimental concurrency investigations only.
* Note: for non-EE/ejb/web contexts (SE) use wlfullclient.jar generated from
* $WLS_INSTALL\wlserver_10.3\server\lib>java -jar wljarbuilder.jar
* 20110106: refactor for generic remote connections
* @author http://wiki.eclipse.org/User:Michael.obrien.oracle.com 20100916
public class Host {
    /** RMI server key name - does not need to resolve under DNS */
    public static String serverDNS[] = {"beowulf5","local"};//,"beowulf6"};
    /** RMI t3 URL */
    public static String serverT3[] = {"t3://1n.n.n.n:7001","t3://1n.n.n.n:7001"};
    private int numberServers = serverDNS.length;
    /** list of server names from above arrays */
    private List<String> serverNames = new ArrayList<String>();
    /** Input context map hashtable entries - For JNDI we are forced to use Hashtable instead of HashMap*/
    private Map<String, Hashtable<String, String>> contextHashtableMap
        = new HashMap<String, Hashtable<String, String>>();
    /** output cached context maps for each remote server */
    private Map<String, Context> rmiCachedContextMap
        = new HashMap<String, Context>();
    /** $Proxy remote objects */
    private Map<String, NodeRemote> remoteObjects                                  
        = new HashMap<String, NodeRemote>();
    /** remote propagation value */
    private Map<String, Integer> stateToSet                                                  
        = new HashMap<String, Integer>();
    /** How many processors are available (real + hyperthreaded) */
    private Map<String, Integer> availableProcessors                                  
        = new HashMap<String, Integer>();
    /** whether the node is accepting requests or not */
    private Map<String, Boolean> nodeUnavailable                                     
        = new HashMap<String, Boolean>();
    /** map of t3 protocol URLs */
    private Map<String, String>  serverIPMap                                               
        = new HashMap<String, String>();
    // verify that all EE libraries available via http://download.oracle.com/docs/cd/E12840_01/wls/docs103/client/jarbuilder.html
    private static final String CONTEXT_FACTORY_NAME = "weblogic.jndi.WLInitialContextFactory";
    private static final String SESSION_BEAN_REMOTE_NAME = "ejb/Node#org.eclipse.persistence.example.distributed.NodeRemote";
    //private String sessionBeanRemoteName = "java:comp/env/ejb/Node"; // EE only
    //private String sessionBeanRemoteName = "org_eclipse_persistence_example_distributed_ClientEARorg_eclipse_persistence_example_distributed_ClientEJB_jarNode_Home" ;
    public Host() {
        // initialize state
        for(int i=0;i<numberServers;i++) {
            // For each server add the name key and corresponding RMI URL
            serverNames.add(serverDNS);
serverIPMap.put(serverDNS[i], serverT3[i]);
nodeUnavailable.put(serverDNS[i], false);
availableProcessors.put(serverDNS[i], 0);
Hashtable<String, String> aTable = new Hashtable<String, String>();
contextHashtableMap.put(serverDNS[i],aTable);
aTable.put(Context.INITIAL_CONTEXT_FACTORY,CONTEXT_FACTORY_NAME);
aTable.put(Context.PROVIDER_URL, serverT3[i]);
public void process() {
// process RMI Objects
try {           
NodeRemote aNode;
StringBuffer aBuffer = new StringBuffer();
// Endlessly generate RMI requests
for(;;) {
// Send messages to entire grid in parallel
for(String remoteServer : remoteObjects.keySet()) {
aNode = remoteObjects.get(remoteServer);
// increment server's pending state
stateToSet.put(remoteServer, stateToSet.get(remoteServer).intValue() + 1);
if(!nodeUnavailable.get(remoteServer)) {
try {
// Issue: One JVM halt will affect the entire distributed app.
// don't let a node failure halt the host
aNode.setState(stateToSet.get(remoteServer)); // this remote call can throw an EJBException wrapping a java.rmi.ConnectException
aBuffer = new StringBuffer("State from: ");
aBuffer.append(remoteServer);
aBuffer.append(" = ");
aBuffer.append(aNode.getState());
System.out.println(aBuffer.toString());
} catch (EJBException e) {
// weblogic.transaction.internal.TimedOutException: Transaction timed out after 29 seconds
// or
// EJBException wrapping a java.rmi.ConnectException if the server is not running
e.printStackTrace();
// mark the current node as down, clear the flag in 5 min
nodeUnavailable.put(remoteServer, true);
} catch (Exception e) {
e.printStackTrace();
public void connect() {
// Setup RMI Objects
try {           
// Establish RMI connections to the session beans
for(String aServer : serverNames) {
Context aContext = null;
try {
aContext = new InitialContext(contextHashtableMap.get(aServer));
rmiCachedContextMap.put(aServer, aContext);
System.out.println("Context for " + aServer + " : " + aContext);
// For qualified name look for weblogic log "EJB Deployed EJB with JNDI name"
Object aRemoteReference = aContext.lookup(SESSION_BEAN_REMOTE_NAME);
System.out.println("Remote Object: " + aRemoteReference);
// narrow the $proxy remote bean
NodeRemote aNode = (NodeRemote) PortableRemoteObject.narrow(aRemoteReference, NodeRemote.class);
remoteObjects.put(aServer, aNode);
System.out.println("Narrowed Session Bean: " + aNode);
// initialize state list
stateToSet.put(aServer, new Integer(0));
} catch (Exception ce) {
// server down throws a javax.naming.CommunicationException inside a java.net.ConnectException
ce.printStackTrace();
// mark the current node as down, clear the flag in 5 min
nodeUnavailable.put(aServer, true);
} catch (Exception e) {
e.printStackTrace();
public Map<String, Hashtable<String, String>> getContextMap() {        return contextHashtableMap;    }
public void setContextMap(Map<String, Hashtable<String, String>> contextMap) {        this.contextHashtableMap = contextMap;    }
public Map<String, Context> getRmiContextMap() {        return rmiCachedContextMap;    }
public void setRmiContextMap(Map<String, Context> rmiContextMap) {        this.rmiCachedContextMap = rmiContextMap;    }
public Map<String, NodeRemote> getRemoteObjects() {        return remoteObjects;    }
public void setRemoteObjects(Map<String, NodeRemote> remoteObjects) {        this.remoteObjects = remoteObjects;    }
public Map<String, Integer> getStateToSet() {        return stateToSet;    }
public void setStateToSet(Map<String, Integer> stateToSet) {        this.stateToSet = stateToSet;    }
public Map<String, Boolean> getNodeUnavailable() {        return nodeUnavailable;    }
public void setNodeUnavailable(Map<String, Boolean> nodeUnavailable) {        this.nodeUnavailable = nodeUnavailable;    }
public Map<String, String> getServerIPMap() {        return serverIPMap;    }
public void setServerIPMap(Map<String, String> aServerIPMap) {        serverIPMap = aServerIPMap;    }
public List<String> getServernames() {        return serverNames;    }
public void setServerNames(List<String> serverNames) {        this.serverNames = serverNames;    }
public int getNumberServers() {        return numberServers;    }
public void setNumberServers(int numberServers) {        this.numberServers = numberServers;    }
public Map<String, Integer> getAvailableProcessors() {        return availableProcessors;    }
public void setAvailableProcessors(Map<String, Integer> availableProcessors) {        this.availableProcessors = availableProcessors;    }
public static void main(String[] args) {
Host host = new Host();
host.connect();
host.process();
Path to run SE client from command line
java -cp .;wls/wlfullclient.jar org.eclipse.persistence.example.distributed.HostRemote Server Deploy logs
Local JVM
####<18-Jan-2011 11:13:45 o'clock AM VET> <Info> <EJB> <mfobrien-pc2> <AdminServer> <[ACTIVE] ExecuteThread: '9' for queue: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1295365425233> <BEA-014021> <The EJB 'Node(Application: _appsdir_org.eclipse.persistence.example.distributed.ClientEAR_ear, EJBComponent: org.eclipse.persistence.example.distributed.ClientEJB.jar)' has been successfully deployed.
The following remote interfaces have been bound into JNDI with the specified JNDI names:>
####<18-Jan-2011 11:13:45 o'clock AM VET> <Info> <EJB> <mfobrien-pc2> <AdminServer> <[ACTIVE] ExecuteThread: '9' for queue: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1295365425233> <BEA-014022> <********
org.eclipse.persistence.example.distributed.NodeRemote is bound with JNDI name:ejb/Node#org.eclipse.persistence.example.distributed.NodeRemote ********>
####<18-Jan-2011 11:13:45 o'clock AM VET> <Info> <EJB> <mfobrien-pc2> <AdminServer> <[ACTIVE] ExecuteThread: '9' for queue: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1295365425233> <BEA-010009> <EJB Deployed EJB with
JNDI name _appsdir_org_eclipse_persistence_example_distributed_ClientEAR_earorg_eclipse_persistence_example_distributed_ClientEJB_jarNode_Home.>
beowulf5 JVM
####<Jan 18, 2011 11:27:46 AM EST> <Info> <EJB> <beowulf5> <AdminServer> <[STANDBY] ExecuteThread: '2' for queue: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1295368066578> <BEA-014021> <The EJB 'Node(Application: _appsdir_org.eclipse.persistence.example.distributed.ClientEAR_ear, EJBComponent: org.eclipse.persistence.example.distributed.ClientEJB.jar)' has been successfully deployed. The following remote interfaces have been bound into JNDI with the specified JNDI names:>
####<Jan 18, 2011 11:27:46 AM EST> <Info> <EJB> <beowulf5> <AdminServer> <[STANDBY] ExecuteThread: '2' for queue: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1295368066578> <BEA-014022> <******** org.eclipse.persistence.example.distributed.NodeRemote is bound with
JNDI name:ejb/Node#org.eclipse.persistence.example.distributed.NodeRemote ********>
####<Jan 18, 2011 11:27:46 AM EST> <Info> <EJB> <beowulf5> <AdminServer> <[STANDBY] ExecuteThread: '2' for queue: 'weblogic.kernel.Default (self-tuning)'> <<WLS Kernel>> <> <> <1295368066578> <BEA-010009> <EJB Deployed EJB with JNDI name _appsdir_org_eclipse_persistence_example_distributed_ClientEAR_earorg_eclipse_persistence_example_distributed_ClientEJB_jarNode_Home.>
local SE client logs
Context for beowulf5 : javax.naming.InitialContext@9980d5
Narrowed Session Bean: ClusterableRemoteRef(7753348759447467175S:10.156.53.10:[7001,7001,-1,-1,-1,-1,-1]:base_domain:AdminServer [7753348759447467175S:10.156.53.10:[7001,7001,-1,-1,-1,-1,-1]:base_domain:AdminServer/292])/292
Context for local : javax.naming.InitialContext@1a897a9
Narrowed Session Bean: ClusterableRemoteRef(-5707697697594367270S:10.156.52.246:[7001,7001,-1,-1,-1,-1,-1]:base_domain:AdminServer [-5707697697594367270S:10.156.52.246:[7001,7001,-1,-1,-1,-1,-1]:base_domain:AdminServer/300])/300
State from: local = 1
State from: beowulf5 = 1
State from: local = 2
State from: beowulf5 = 2thank you
Glad to help out.
/Michael