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Creating your first EJB3 Project in eclipse on JBoss Server

This tutorial will teach you on how to setup and run an ejb application.

What you need (noted are where I installed my versions):
1.) Jboss 5 (jboss-5.1.0.GA)
2.) eclipse-jee
3.) ojdbc14 (C:\jboss-5.1.0.GA\server\default\lib)

Steps:

1.) Create a new EJB project.
  a.) In your eclipse select File->New->Other->EJB->EJB Project. I named mine ipielEJB
b.) Click next
  c.) Click next
  d.) Check Generate ejb-jar.xml, then click Finish
2.) Add a persistence.xml in your project (inside META-INF folder) (See file below)
3.) Create a new package com.kbs
4.) Create a new class Book.java annotate as Entity (See file below)
5.) Create 2 interface BookBeanLocal and BookBeanRemote, annotate with Local and Remote (See files below)
6.) Create a new class BookBean that implements BookBeanLocal and BookBeanRemote. Annotate with Stateless. (See file below)
7.) Create ipielEJB-ds.xml. For format look here: C:\jboss-5.1.0.GA\docs\examples\jca
8.) Our ejb project is almost finish by now.
9.) Configure your jboss server
10.) Deploy ipielEJB to jboss (See screenshot)
11.) You will know if the deployment is successful if you got no error on Console log and can see the following log.

Now to test the EJB bean.
1.) In the same project create a package com.kbs.test
2.) In the newly create package create a class BookClient (See class below)
3.) In ejbModule folder create a new file jndi.properties (See file below)
4.) Run the client. The below screen shot is how the project should look like. Also the Book run log can be seen.

Book.java

package com.kbs;

import java.io.Serializable;

import javax.persistence.*;

@Entity
@Table(name = "book")
@SequenceGenerator(name = "book_sequence", sequenceName = "book_id_seq")
public class Book implements Serializable {
 private static final long serialVersionUID = 7422574264557894633L;
 private Integer id;
 private String title;
 private String author;

 public Book() {
  super();
 }

 public Book(Integer id, String title, String author) {
  super();
  this.id = id;
  this.title = title;
  this.author = author;
 }

 @Override
 public String toString() {
  return "Book: " + getId() + " Title " + getTitle() + " Author "
    + getAuthor();
 }

 public String getAuthor() {
  return author;
 }

 public void setAuthor(String author) {
  this.author = author;
 }

 @Id
 @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "book_sequence")
 public Integer getId() {
  return id;
 }

 public void setId(Integer id) {
  this.id = id;
 }

 public String getTitle() {
  return title;
 }

 public void setTitle(String title) {
  this.title = title;
 }
}

BookBean.java

package com.kbs;

import java.util.Iterator;
import java.util.List;

import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;

@Stateless
public class BookBean implements BookBeanLocal, BookBeanRemote {
 @PersistenceContext
 EntityManager em;
 public static final String RemoteJNDIName = BookBean.class
   .getSimpleName() + "/remote";
 public static final String LocalJNDIName = BookBean.class
   .getSimpleName() + "/local";

 public void test() {
  Book book = new Book(null, "Hello Java Bean I!", "Edward");
  em.persist(book);
  Book book2 = new Book(null, "Hello Java Bean II", "czetsuya");
  em.persist(book2);
  Book book3 = new Book(null, "Hello Java Bean III",
    "ipiel");
  em.persist(book3);
  System.out.println("list some books");
  List someBooks = em.createQuery("from Book b where b.author=:name")
    .setParameter("name", "czetsuya").getResultList();
  for (Iterator iter = someBooks.iterator(); iter.hasNext();) {
   Book element = (Book) iter.next();
   System.out.println(element);
  }
  System.out.println("List all books");
  List allBooks = em.createQuery("from Book").getResultList();
  for (Iterator iter = allBooks.iterator(); iter.hasNext();) {
   Book element = (Book) iter.next();
   System.out.println(element);
  }
  System.out.println("delete a book");
  em.remove(book2);
  System.out.println("List all books");
  allBooks = em.createQuery("from Book").getResultList();
  for (Iterator iter = allBooks.iterator(); iter.hasNext();) {
   Book element = (Book) iter.next();
   System.out.println(element);
  }
 }
}

BookBeanLocal.java

package com.kbs;

import javax.ejb.Local;

@Local
public interface BookBeanLocal {
 void test();
}

BookBeanRemote.java

package com.kbs;

import javax.ejb.Remote;

@Remote
public interface BookBeanRemote {
 void test();
}

BookClient.java

package com.kbs.test;

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.naming.NamingException;

import com.kbs.BookBean;
import com.kbs.BookBeanRemote;

public class BookClient {
 public static void main(String[] args) {
  Context context;
  try {
   context = new InitialContext();
   BookBeanRemote beanRemote = (BookBeanRemote) context
     .lookup(BookBean.RemoteJNDIName);
   beanRemote.test();
  } catch (NamingException e) {
   e.printStackTrace();
  }
 }
}

ejb-jar.xml

<?xml version="1.0" encoding="UTF-8"?>
<ejb-jar version="3.0" xmlns="http://java.sun.com/xml/ns/javaee"
 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">
 <display-name>ipielEJB</display-name>
</ejb-jar>

ipielEJB-ds.xml

<datasources>
 <local-tx-datasource>
  <jndi-name>ipielEJBDS</jndi-name>
  <connection-url>jdbc:oracle:thin:@localhost:1521:xe</connection-url>
  <driver-class>oracle.jdbc.driver.OracleDriver</driver-class>
  <user-name>demo</user-name>
  <password>demo</password>
  <exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.OracleExceptionSorter
  </exception-sorter-class-name>
  <metadata>
   <type-mapping>Oracle9i</type-mapping>
  </metadata>
 </local-tx-datasource>
</datasources>

MANIFEST.MF

Manifest-Version: 1.0
Class-Path:

persistence.xml

<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="ipielEJB">
  <jta-data-source>java:/ipielEJBDS</jta-data-source>
  <properties>
   <property name="hibernate.hbm2ddl.auto" value="create-drop" />
  </properties>
 </persistence-unit>
</persistence>

jndi.properties

java.naming.factory.initial=org.jnp.interfaces.NamingContextFactory
java.naming.factory.url.pkgs=org.jboss.naming:org.jnp.interfaces
java.naming.provider.url=localhost:1099

Commonly encoutered errors:

1.) Deployment "jboss.jca:name=ejb3ProjectDS,service=DataSourceBinding" is in error due to the following reason(s): ** NOT FOUND Depends on 'jboss.jca:name=ejb3ProjectDS,service=DataSourceBinding' **
Deployment "<UNKNOWN jboss.j2ee:jar=FirstEjb3Tutorial.jar,name=BookTestBean,service=EJB3>" is in error due to the following reason(s): ** UNRESOLVED Demands 'persistence.unit:unitName=#FirstEjb3Tutorial' **
-Simply means your ojdbc14.jar is not where it should be on C:\jboss-5.1.0.GA\server\default\lib

2.) Failed to resolve schema nsURI= location=persistence
-persistence.xml is missing version, xmlns, etc tag

3.) EJBException unknown entity
-Book entity (Book.java) is not properly configured

4.) javax.naming.NoInitialContextException: Need to specify class name in environment or system property, or as an applet parameter, or in an application resource file: java.naming.factory.initial
-Missing or unconfigured jndi.properties

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