Unable to call exported client methods of EJB session bean remote interface

Question

I am unable to call client methods of a BC4J application module deployed as a Session EJB to Oracle 8i at the client side of my multi-tier application. There is no documentation, and I am unable to understand how I should do it.
A business components project has been created. For instance, its application module is called BestdataModule. A few custom methods have been added to BestdataModuleImpl.java file, for instance:
public void doNothingNoArgs() {
public void doNothingOneArg(String astr) {
public void setCertificate(String userName, String userPassword) {
theCertificate = new Certificate(userName, userPassword);
public String getPermission() {
if (theCertificate != null)
{if (theCertificate.getPermission())
{return("Yes");
else return("No, expired");
else return("No, absent");
theCertificate being a protected class variable and Certificate being a class, etc.
The application module has been tested in the local mode, made remotable to be deployed as EJB session bean, methods to appear at the client side have been selected. The application module has been successfully deployed to Oracle 8.1.7 and tested in the remote mode. A custom library containing BestdataModuleEJBClient.jar and BestDataCommonEJB.jar has been created.
Then I try to create a client basing on Example Oracle8i/EJB Client snippet:
package bestclients;
import java.lang.*;
import java.sql.*;
import java.util.*;
import javax.naming.*;
import oracle.aurora.jndi.sess_iiop.*;
import oracle.jbo.*;
import oracle.jbo.client.remote.ejb.*;
import oracle.jbo.common.remote.*;
import oracle.jbo.common.remote.ejb.*;
import oracle.jdeveloper.html.*;
import bestdata.client.ejb.*;
import bestdata.common.ejb.*;
import bestdata.common.*;
import bestdata.client.ejb.BestdataModuleEJBClient;
public class BestClients extends Object {
static Hashtable env = new Hashtable(10);
public static void main(String[] args) {
String ejbUrl = "sess_iiop://localhost:2481:ORCL/test/TESTER/ejb/bestdata.BestdataModule";
String username = "TESTER";
String password = "TESTER";
Hashtable environment = new Hashtable();
environment.put(javax.naming.Context.URL_PKG_PREFIXES, "oracle.aurora.jndi");
environment.put(Context.SECURITY_PRINCIPAL, username);
environment.put(Context.SECURITY_CREDENTIALS, password);
environment.put(Context.SECURITY_AUTHENTICATION, ServiceCtx.NON_SSL_LOGIN);
BestdataModuleHome homeInterface = null;
try {
Context ic = new InitialContext(environment);
homeInterface = (BestdataModuleHome)ic.lookup(ejbUrl);
catch (ActivationException e) {
System.out.println(e.getMessage());
e.printStackTrace();
System.exit(1);
catch (CommunicationException e) {
System.out.println(e.getMessage());
e.printStackTrace();
System.exit(1);
catch (NamingException e) {
System.out.println(e.getMessage());
e.printStackTrace();
System.exit(1);
try {
System.out.println("Creating a new EJB instance");
RemoteBestdataModule remoteInterface = homeInterface.create();
// Method calls go here!
// e.g.
// System.out.println(remoteInterface.foo());
catch (Exception e) {
System.out.println(e.getMessage());
e.printStackTrace();
It doesnt cause any errors. However, how must I call methods? The public interface RemoteBestdataModule has no such methods:
void doNothingNoArgs();
void doNothingOneArg(java.lang.String astr);
void setCertificate(java.lang.String userName, java.lang.String userPassword);
java.lang.String getPermission();
Instead of that it has the following methods:
oracle.jbo.common.remote.PiggybackReturn doNothingNoArgs(byte[] _pb) throws oracle.jbo.common.remote.ejb.RemoteJboException, java.rmi.RemoteException;
oracle.jbo.common.remote.PiggybackReturn doNothingOneArg(byte[] _pb, java.lang.String astr) throws oracle.jbo.common.remote.ejb.RemoteJboException, java.rmi.RemoteException;
oracle.jbo.common.remote.PiggybackReturn customQueryExec(byte[] _pb, java.lang.String aQuery) throws oracle.jbo.common.remote.ejb.RemoteJboException, java.rmi.RemoteException;
oracle.jbo.common.remote.PiggybackReturn setCertificate(byte[] _pb, java.lang.String userName, java.lang.String userPassword) throws oracle.jbo.common.remote.ejb.RemoteJboException, java.rmi.RemoteException;
oracle.jbo.common.remote.PiggybackReturn getPermission(byte[] _pb) throws oracle.jbo.common.remote.ejb.RemoteJboException, java.rmi.RemoteException;
I cannot call those methods. I can see how they are called in BestdataModuleEJBClient.java file:
public void doNothingNoArgs() throws oracle.jbo.JboException {
try {
oracle.jbo.common.remote.PiggybackReturn _pbRet = mRemoteAM.doNothingNoArgs(getPiggyback());
processPiggyback(_pbRet.mPiggyback);
if (_pbRet.isReturnStreamValid()) {
return;
catch (oracle.jbo.common.remote.ejb.RemoteJboException ex) {
processRemoteJboException(ex);
catch (java.rmi.RemoteException ex) {
processRemoteJboException(ex);
throw new oracle.jbo.JboException("Marshall error");
However, I cannot call getPiggyback() function! It is a protected method, it is available to the class BestdataModuleEJBClient which extends EJBApplicationModuleImpl, but it is unavailable to my class BestClients which extends Object and is intended to extend oracle.jdeveloper.html.WebBeanImpl!
It seems to me that I mustnt use RemoteBestdataModule interface directly. Instead of that I must use the public class BestdataModuleEJBClient that extends EJBApplicationModuleImpl and implements BestdataModule interface. It contains all methods required without additional arguments (see just above). However, how must I create an object of BestdataModuleEJBClient class? That is a puzzle. Besides my custom methods the class has only two methods:
protected bestdata.common.ejb.RemoteBestdataModule mRemoteAM;
/*This is the default constructor (do not remove)*/
public BestdataModuleEJBClient(RemoteApplicationModule remoteAM) {
super(remoteAM);
mRemoteAM = (bestdata.common.ejb.RemoteBestdataModule)remoteAM;
public bestdata.common.ejb.RemoteBestdataModule getRemoteBestdataModule() {
return mRemoteAM;
It looks like the remote application module must already exist! In despair I tried to put down something of the kind at the client side:
RemoteBestdataModule remoteInterface = homeInterface.create();
BestdataModuleEJBClient dm = new BestdataModuleEJBClient(remoteInterface);
dm.doNothingNoArgs();
Of course, it results in an error.
System Output: null
System Error: java.lang.NullPointerException
System Error: oracle.jbo.common.PiggybackOutput oracle.jbo.client.remote.ApplicationModuleImpl.getPiggyForRemovedObjects(oracle.jbo.common.PiggybackOutput) (ApplicationModuleImpl.java:3017)
System Error: byte[] oracle.jbo.client.remote.ApplicationModuleImpl.getPiggyfront(boolea
System Error: n) (ApplicationModuleImpl.java:3059)
System Error: byte[] oracle.jbo.client.remote.ApplicationModuleImpl.getPiggyback() (ApplicationModuleImpl.java:3195)
System Error: void bestdata.client.ejb.BestdataModuleEJBClient.doNothingNoArgs() (BestdataModuleEJBClient.java:33)
System Error: void bes
System Error: tclients.BestClients.main(java.lang.String[]) (BestClients.java:76)
I have studied a lot of documents in vain. I have found only various senseless discourses:
"Use the Application Module Wizard to make the Application Module remotable and export the method. This will generate an interface for HrAppmodule (HrAppmodule.java in the Common package) which contains the signature for the exported method promoteAllEmps(). Then, deploy the Application Module. Once the Application Module has been deployed, you can use the promoteAllEmps() method in your client-side programs. Calls to the promoteAllEmps() method in client-side programs will result in calls to the promote() method in the application tier."
However, I have failed to find a single line of code explaining how it should be called.
Can anybody help me?
Best regards,
Svyatoslav Konovaltsev,
[email protected]
null

Answer 1

Dear Steven,
1. Thank you very much. It seems to me that the problem is solved.
2. "I logged into Metalink but it wants me to put in both a tar number and a country name to see your issue." It was the United Kingdom, neither the US nor Russia if you mean my issue.
I reproduce the text to be written by everyone who encounters the same problem:
package bestclients;
import java.util.Hashtable;
import javax.naming.*;
import oracle.jbo.*;
public class BestdataHelper {
public static ApplicationModule createEJB()
throws ApplicationModuleCreateException {
ApplicationModule applicationModule = null;
try {
Hashtable environment = new Hashtable(8);
environment.put(Context.INITIAL_CONTEXT_FACTORY, JboContext.JBO_CONTEXT_FACTORY);
environment.put(JboContext.DEPLOY_PLATFORM, JboContext.PLATFORM_EJB);
environment.put(Context.SECURITY_PRINCIPAL, "TESTER");
environment.put(Context.SECURITY_CREDENTIALS, "TESTER");
environment.put(JboContext.HOST_NAME, "localhost");
environment.put(JboContext.CONNECTION_PORT, new Integer("2481"));
environment.put(JboContext.ORACLE_SID, "ORCL");
environment.put(JboContext.APPLICATION_PATH, "/test/TESTER/ejb");
Context ic = new InitialContext(environment);
ApplicationModuleHome home = (ApplicationModuleHome)ic.lookup("bestdata.BestdataModule");
applicationModule = home.create();
applicationModule.getTransaction().connect("jdbc:oracle:kprb:@");
applicationModule.setSyncMode(ApplicationModule.SYNC_IMMEDIATE);
catch (NamingException namingException) {
throw new ApplicationModuleCreateException(namingException);
return applicationModule;
package bestclients;
import bestdata.common.*;
import certificate.*;
public class BestClients extends Object {
public static void main(String[] args) {
BestdataModule bestdataModule = (BestdataModule)BestdataHelper.createEJB();
Certificate aCertificate = new Certificate("TESTER", "TESTER");
//calling a custom method!!
bestdataModule.passCertificate(aCertificate);
Thank you very much,
Best regards,
Svyatoslav Konovaltsev.
[email protected]
null