How can I deploy a simple stateless ssion EJB and call it from a standalone client

Question

Hi,
I'm creating s simple staless session EJB that has a method that takes a name and prints "Hello" + name. This EJB is in a package called "com.demos.mydemo.ejbs.hello"
How can I deploy this to OC4J?
How can I call it from a standalone client(no JSP, no servlets)?
In Sun's J2EE is very easy to deploy and I don't have to know any XML stuff.
can I use the .ear file created by the Sun's "deploytool" to deploy my EJB to OC4J?
This is the code at I'm using and it works on Sun's j2sdkee1.2.1:
///////// Remote /////////
package com.demos.mydemo.ejbs.hello;
import java.rmi.RemoteException;
import javax.ejb.EJBObject;
public interface Hello extends EJBObject {
public String sayHello(String name) throws RemoteException;
///////// Home //////////
package com.demos.mydemo.ejbs.hello;
import java.rmi.RemoteException;
import javax.ejb.EJBHome;
import javax.ejb.CreateException;
public interface HelloHome extends EJBHome {
public Hello create() throws CreateException, RemoteException;
/////////// Bean class ///////////
package com.demos.mydemo.ejbs.hello;
import java.rmi.RemoteException;
import javax.ejb.SessionBean;
import javax.ejb.SessionContext;
import javax.ejb.CreateException;
import javax.ejb.EJBException;
import java.sql.Connection;
import java.sql.SQLException;
//import java.sql.PreparedStatement;
import javax.sql.DataSource;
import javax.naming.NamingException;
import javax.naming.InitialContext;
public class HelloEJB implements SessionBean {
private SessionContext context;
private Connection con;
private String dbName =
"java:comp/env/jdbc/Oracle";
public HelloEJB() {}
public void setSessionContext (SessionContext context) {
this.context = context;
public void ejbCreate() throws CreateException {
try {
makeConnection();
catch (Exception e) {
System.err.println("HelloEJB: exception in ejbCreate:" + e.getMessage());
e.printStackTrace();
throw new CreateException(e.getMessage());
public void ejbActivate() {
public void ejbPassivate() {
public void ejbRemove() {
try {
con.close();
catch (SQLException ex) {
throw new EJBException("HelloEJB: exception in ejbRemove: " + ex.getMessage());
public String sayHello(String name) {
return "Hello " + name;;
private void makeConnection() throws NamingException, SQLException {
try {
InitialContext ic = new InitialContext();
DataSource ds = (DataSource) ic.lookup(dbName);
con = ds.getConnection();
catch (Exception e) {
System.err.println("HelloEJB: exception in makeConnection:" + e.getMessage() );
e.printStackTrace();
//////////// EJB client that uses a stateless session bean
package com.demos.mydemo.ejbs.hello;
import java.io.*;
import java.sql.*;
import javax.sql.*;
import javax.naming.Context;
import javax.naming.InitialContext;
import javax.rmi.PortableRemoteObject;
public class HelloClient {
public static void main(String[] args) {
try {
Context initial = new InitialContext();
Object objref = initial.lookup("HelloSession");
HelloHome home = (HelloHome)PortableRemoteObject.narrow(objref,HelloHome.class);
Hello h = home.create();
String msg = h.sayHello("John Doe");
System.out.println(msg);
//h.remove();
} catch (Exception ex) {
System.err.println("Caught an exception." );
ex.printStackTrace();
Thanks
Nabil
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Answer 1

<BLOCKQUOTE><font size="1" face="Verdana, Arial, Helvetica">quote:</font><HR>Originally posted by Nabil Khalil ([email protected]):
I deployed and .ear file created by Sun's J2EE deployment tool on the OC4J. It looks that it was deployed fine -- did not get a deployment error.
When I run the client I'm getting the following error: Caught an exception.
javax.naming.CommunicationException: Can't find SerialContextProvider
at com.sun.enterprise.naming.SerialContext.getProvider(SerialContext.java:60)
at com.sun.enterprise.naming.SerialContext.<init>(SerialContext.java:79)
at com.sun.enterprise.naming.SerialInitContextFactory.getInitialContext(SerialInitContextFactory.java:54)
at javax.naming.spi.NamingManager.getInitialContext(NamingManager.java:668)
at javax.naming.InitialContext.getDefaultInitCtx(InitialContext.java:246)
at javax.naming.InitialContext.init(InitialContext.java:222)
at javax.naming.InitialContext.<init>(InitialContext.java:178)
at com.equifax.fms.ejbs.hello.HelloClient.main(HelloClient.java:18)
This makes me think that the client can't see the deployed EJB on the OC4J.
How can I fix this problem?
Thanks
Nabil
<HR></BLOCKQUOTE>
Nabil -
Your standalone client needs to obtain certain server-dependent properties. You can provide them in your code or grab them via a properties file.
For Orion - you need essentially the following setup, filling in your own information...
Define your standalone client class with "main" etc (this is orion specific - should work for 9i AS as well - perhaps there are some differences)
public class SomeClass {
try {
Properties p = new Properties();
p.setProperty("java.naming.factory.initial",
"com.evermind.server.ApplicationClientInitialContextFactory");
p.setProperty("java.naming.security.principal","server_admin_name");
p.setProperty("java.naming.security.credentials","server_password");
// THEN you can get your intitial context reference
InitialContext initial = new InitialContext (p);...........
Then go about your business.....
A good book to get is called "Professional Java Server Programming J2EE Edition" - there happens to be a reasonable amount of Orion/OCJ4 centric information since one of the authors is Karl Avedal - one of the principals behind Orion. Go out to java.sun.com and look at some of the J2EE tutorials - unfortunately a lot of it is hidden behind the J2EE Deployer, but you will get a good sense of what goes into outside-the-container standalone clients.
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