[jboss-user] [JBoss Getting Started Documentation] - javax.naming.NamingException : could not dereference object[

[ashwinD]

HI Someone please help me i am new to entity beans. I deployed my application successfully to jboss-4.0.4.GA server (default) i don't have ejb3 support. In my application i want to display the records of Book table (Library database)from mysql. So i created 1st entity bean first & then i developed servlet & run xdoclet after creating interfaces i make all possible changes & lastly managed to deployed the application 
Now my problem is that when i request the servlet "ReadData" through browser then Exception is arises.

i am using 
JBoss IDE1.6 
JBoss 4.0.4.GA server
mysql 5 with mysql connector
Debian Etch

my deployment descriptors are:

ejb-jar.xml is


<ejb-jar >
<![CDATA[No Description.]]>
<display-name>exampleBMPJAR</display-name>
 <enterprise-beans>           
 
	 <![CDATA[Description for exampleBMP]]>      
	<display-name>Name for exampleBMP</display-name>
	<ejb-name>exampleBMP</ejb-name>
	 example.BMP.interfaces.exampleBMPHome
	example.BMP.interfaces.exampleBMP      	

<local-home>example.BMP.interfaces.exampleBMPLocalHome</local-home>         	

example.BMP.interfaces.exampleBMPLocal         	

<ejb-class>example.BMP.ejb.exampleBMPBean</ejb-class>
	<persistence-type>Bean</persistence-type>
	<prim-key-class>example.BMP.interfaces.exampleBMPPK</prim-key-class>
	False
<resource-ref>
	<res-ref-name>jdbc/bmp-exBMP</res-ref-name> 
	<res-type>javax.sql.DataSource</res-type>
	 <res-auth>Container</res-auth>
	 <res-sharing-scope>Shareable</res-sharing-scope>
 </resource-ref>

 </ejb-jar>

jboss.xml is 

 <enterprise-beans>
    
  <ejb-name>exampleBMP</ejb-name>
  <jndi-name>exampleBMPBean</jndi-name>
  
  </enterprise-beans>

jboss-web.xml is 

<jboss-web>
  <ejb-ref>
	<ejb-ref-name>ejb/exampleBMP</ejb-ref-name>
	<jndi-name>ejb/exampleBMPBean</jndi-name>
</ejb-ref>
</jboss-web>

web.xml is
 
	<servlet-name>ReadData</servlet-name>
	<display-name>Name for ReadData</display-name>
	<![CDATA[Description for ReadData]]>
	<servlet-class>example.BMP.Web.ReadData</servlet-class>
 
<servlet-mapping>
	<servlet-name>ReadData</servlet-name>
	<url-pattern>/ReadData</url-pattern>
</servlet-mapping>
<ejb-ref >
	<![CDATA[Reference to the exampleBMP EJB]]>
	<ejb-ref-name>ejb/exampleBMP</ejb-ref-name>
	<ejb-ref-type>BMP</ejb-ref-type>
	example.BMP.interfaces.exampleBMPHome
	example.BMP.interfaces.exampleBMP
	<local-home>example.BMP.interfaces.exampleBMPLocalHome</local-home>
	example.BMP.interfaces.exampleBMPLocal
</ejb-ref>
</web-app>

My "ReadData" Servlet is
public class ReadData extends HttpServlet {
exampleBMPHome home;
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException,IOException 
{			resp.setContentType("text/html");
	PrintWriter out = resp.getWriter();
	try{
		Context ctx =new InitialContext();
		Object obj =ctx.lookup("java:/comp/env/ejb/exampleBMP");
		exampleBMPHome home =(exampleBMPHome)PortableRemoteObject.narrow(obj,exampleBMPHome.class);
		ResultSet rs=home.DisplayData();String s1 = rs.getString("BName");
		String	s2 = rs.getString("BAuthor");
		int	s3 = rs.getInt("BPrice");
		int     s4 = rs.getInt("LCno");
		while(rs.next()) 
		{
			out.print("");
			out.print("============================================");
			out.println("<h3><FONT COLOR=RED> The Book Name is =</h3><h2>"+s1);
			out.print("</h2>");
			out.println("<h3><FONT COLOR=RED> The Author Name is =</h3><h2>"+s2);
			out.print("</h2>");
			out.println("<h3><FONT COLOR=RED> The Price of Book is =</h3><h2>"+s3);
			out.print("</h2>");
			out.println("<h3><FONT COLOR=RED> The Library card No. is=</h3><h2>"+s4);
			out.print("</h2>");
			out.println("==============================================");
			out.print("");
			out.print("");
		}
	} 
catch(Exception e){	
		System.out.println("The Exception arises is ="+e);
                            }	
		finally {
                         		out.println("");
                            	out.close();
  	                       }
	}
}

my interfaces r 
exampleBMP is

public interface exampleBMP extends javax.ejb.EJBObject
{
}
& same exampleBMPLocal interface

exampleBMPHome is
public interface exampleBMPHome  extends javax.ejb.EJBHome
{
	public static final String COMP_NAME="java:comp/env/ejb/exampleBMP";
              public static final String JNDI_NAME="exampleBMP";
 	public example.BMP.interfaces.exampleBMP create()throws javax.ejb.CreateException,java.rmi.RemoteException;   public example.BMP.interfaces.exampleBMP findByPrimaryKey(exampleBMPPK key) throws javax.ejb.FinderException, java.rmi.RemoteException;
public ResultSet DisplayData() throws java.rmi.RemoteException;
}

and same exampleBMPLocalHome interface

Nw what is the exact problem in servlet coding where i put 
Object obj =ctx.lookup("java:/comp/env/ejb/exampleBMP");
whether this is creating problem me as::
javax.naming.NamingException : could not dereference object[Root cause is javax.naming.NameNotFoundException:ejb not bound]
Please Help me.....Ashwin Dhiware BE(Computers) 

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