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Accessing Remote EJB

I spent last week creating a small 3 tier application using NetBeans and reading documentation on how to process... so I have a fair understanding of EJB. I succeeded in deploying my EJB module and then my Web module (war) onto the a Sun App Server on my local machine. (my EJB has both remote & local interface)

I created 1 simple EJB with 1 method and eveything works fine if I access my EJB from my web tier using these methods:

@EJB

private CalculatriceRemote calculatrice;

InitialContext ic;

try{

ic =new InitialContext();

Object ref = ic.lookup("java:comp/env/ejb/Foo");

CalculatriceRemote calc = (CalculatriceRemote)PortableRemoteObject.narrow(ref,CalculatriceRemote.class);

result = calc.additionner(x,y);

}catch (NamingException ex){

}

...

Now what I am looking for, is to deploy the EJB part on ANOTHER sun App server (on another physical machine). And I would like to access it from my Web tier which is on my local machine.

I googled without any good result... some talk about JNDI, some talk about the sun-web.xml file, some about CORBA, some about WebLogic. This is really confusing.

I am new to this so I was wondering if anyone could give me a good starting trail or hints on what I need to know exactly to achieve this...

Thanks

[1641 byte] By [moriaka] at [2007-11-26 18:11:38]

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# 1

This is covered in our EJB FAQ :https://glassfish.dev.java.net/javaee5/ejb/EJB_FAQ.html#cross-appserverremoteref --ken

ksaksa at 2007-7-9 5:44:16 >

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# 2

[nobr]Hey

Thanks for the answer, it helped a lot. It gave me a good hint on where to look at...

But after trying many different things I still get stuck with a javax.naming.NameNotFoundException. I think I am doing it write but the thing I really can't be sure about is where exactly does this error comes from... it is from my servlet or... does it really goes up to the other server and then does not find the Bean...

Here is how I setup my code perhaps you will see what is it I am doing wrong.

1) In the war-module deployed on Server1

web.xml

<ejb-ref>

<ejb-ref-name>Test</ejb-ref-name>

<ejb-ref-type>Session</ejb-ref-type>

<home>ejb.TestLocal</home>

<remote>ejb.TestRemote</remote>

<ejb-link>ejb.TestBean</ejb-link>

</ejb-ref>

sun-web.xml

<ejb-ref>

<ejb-ref-name>Test</ejb-ref-name>

<jndi-name>corbaname:iiop:192.168.209.132:3700#ejb/TestRemote</jndi-name>

</ejb-ref>

In the servlet

try {

InitialContext ic = new InitialContext();

//Object ref = ic.lookup("corbaname:iiop:192.168.209.132:3700#ejb/TestRemote");

Object ref = ic.lookup("java:comp/env/ejb/Test");

TestRemote testBean = (TestRemote)PortableRemoteObject.narrow(ref, TestRemote.class);

out.println(testBean.businessMethod());

}

catch (Exception e) {

out.println(e.getClass().getName());

out.println("<br>");

out.println(e.getMessage());

}

2) In the ejb-module deployed on Server2

My Bean

package ejb;

import javax.ejb.Stateless;

@Stateless

public class TestBean implements TestRemote, TestLocal {

/** Creates a new instance of TestBean */

public TestBean() {

}

public int businessMethod() {

return 0;

}

My Bean's Remote Interface

package ejb;

import javax.ejb.Local;

@Local

public interface TestLocal {

int businessMethod();

}

My Bean's Local Interface

package ejb;

import javax.ejb.Remote;

@Remote

public interface TestRemote {

int businessMethod();

}

JNDI name on Server2 (from server console)

ejb.TestRemote

demo.ejb3.calculatrice.CalculatriceRemote__3_x_Internal_RemoteBusinessHome__

demo.ejb3.calculatrice.CalculatriceRemote#demo.ejb3.calculatrice.CalculatriceRemote

ejb.TestRemote__3_x_Internal_RemoteBusinessHome__

jdbc (folder)

UserTransaction

ejb (folder)

ejb.TestRemote#ejb.TestRemote

demo.ejb3.calculatrice.CalculatriceRemote

I have been messing arround with this for 3 days, I'm sure I am just not typing the right JNDI reference somewhere... can anyone help me figure this out?

Thanks[/nobr]

moriaka at 2007-7-9 5:44:16 >

# 3

Few things. First, if you don't explicitly assign the global JNDI name of the ejb it will

default to the fully qualified name of the Remote interface.That would make it

"ejb.TestRemote" instead of "ejb/TestRemote".

On the client side, the ejb-ref is incorrect. Since it's referring to a 3.0 remote business interface,

there is no <home> element needed. You also don't need the <ejb-link> since that only

applies when you're referring to another ejb within the same .ear.

<ejb-ref>

<ejb-ref-name>Test</ejb-ref-name>

<ejb-ref-type>Session</ejb-ref-type>

<remote>ejb.TestRemote</remote>

</ejb-ref>

Finally, the portion of the lookup string after "java:comp/env/" must match the content of

the ejb-ref-name exactly. There is no automatic pre-pending of "ejb". So, based on

the above ejb-ref, the code should be ic.lookup("java:comp/env/Test");

ksaksa at 2007-7-9 5:44:16 >

# 4

Hi, thanks for the reply... ok I fixed the code as you told. Here is the result of the modification:

SERVER:

I removed the deployment descriptor from the ejb module so now, on the server console, I can see that the JNDI name is, as you told, ejb.TestRemote.

CLIENT:

web.xml

<ejb-ref>

<ejb-ref-name>Test</ejb-ref-name>

<ejb-ref-type>Session</ejb-ref-type>

<remote>ejb.TestRemote</remote>

</ejb-ref>

sun-web.xml

<ejb-ref>

<ejb-ref-name>Test</ejb-ref-name>

<jndi-name>corbaname:iiop:192.168.209.132:3700#ejb/TestRemote</jndi-name>

</ejb-ref>

Servlet code

try {

InitialContext ic = new InitialContext();

Object ref = ic.lookup("java:comp/env/Test");

TestRemote testBean = (TestRemote)PortableRemoteObject.narrow(ref, TestRemote.class);

out.println(testBean.businessMethod());

}

catch (Exception e) {

out.println(e.getClass().getName());

out.println("

");

out.println(e.getMessage());

}

Also, I get this error when I deploy my web app:

"IOP00100009: (BAD_PARAM) string_to_object conversion failed due to bad bad schema specific part"

org.omg.CORBA.BAD_PARAM:vmcid: OMG minor code: 9 completed: No

at com.sun.corba.ee.impl.logging.OMGSystemException.soBadSchemaSpecific(OMGSystemException.java:1081)

at com.sun.corba.ee.impl.logging.OMGSystemException.soBadSchemaSpecific(OMGSystemException.java:1099)

at com.sun.corba.ee.impl.resolver.INSURLOperationImpl.resolveCorbaname(INSURLOperationImpl.java:188)

at com.sun.corba.ee.impl.resolver.INSURLOperationImpl.resolveINSURL(INSURLOperationImpl.java:127)

at com.sun.corba.ee.impl.resolver.INSURLOperationImpl.operate(INSURLOperationImpl.java:117)

at com.sun.corba.ee.impl.orb.ORBImpl.string_to_object(ORBImpl.java:929)

at com.sun.enterprise.naming.NamingManagerImpl.lookup(NamingManagerImpl.java:831)

at com.sun.enterprise.naming.java.javaURLContext.lookup(javaURLContext.java:156)

at com.sun.enterprise.naming.SerialContext.lookup(SerialContext.java:307)

at javax.naming.InitialContext.lookup(InitialContext.java:351)

at servlet.TestServlet.processRequest(TestServlet.java:40)

at servlet.TestServlet.doGet(TestServlet.java:60)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:707)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:820)

at org.apache.catalina.core.ApplicationFilterChain.servletService(ApplicationFilterChain.java:397)

at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:278)

at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:566)

at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:536)

at org.apache.catalina.core.StandardContextValve.invokeInternal(StandardContextValve.java:240)

at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:179)

at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:566)

at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:73)

at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:182)

at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:566)

at com.sun.enterprise.web.VirtualServerPipeline.invoke(VirtualServerPipeline.java:120)

at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:939)

at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:137)

at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:566)

at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:536)

at org.apache.catalina.core.ContainerBase.invoke(ContainerBase.java:939)

at org.apache.coyote.tomcat5.CoyoteAdapter.service(CoyoteAdapter.java:231)

at com.sun.enterprise.web.connector.grizzly.ProcessorTask.invokeAdapter(ProcessorTask.java:667)

at com.sun.enterprise.web.connector.grizzly.ProcessorTask.processNonBlocked(ProcessorTask.java:574)

at com.sun.enterprise.web.connector.grizzly.ProcessorTask.process(ProcessorTask.java:844)

at com.sun.enterprise.web.connector.grizzly.ReadTask.executeProcessorTask(ReadTask.java:287)

at com.sun.enterprise.web.connector.grizzly.ReadTask.doTask(ReadTask.java:212)

at com.sun.enterprise.web.connector.grizzly.TaskBase.run(TaskBase.java:252)

at com.sun.enterprise.web.connector.grizzly.WorkerThread.run(WorkerThread.java:75)

Caused by: org.omg.CosNaming.NamingContextPackage.NotFound: IDL:omg.org/CosNaming/NamingContext/NotFound:1.0

at org.omg.CosNaming.NamingContextPackage.NotFoundHelper.read(NotFoundHelper.java:72)

at org.omg.CosNaming._NamingContextExtStub.resolve_str(_NamingContextExtStub.java:165)

at com.sun.corba.ee.impl.resolver.INSURLOperationImpl.resolveCorbaname(INSURLOperationImpl.java:184)

... 35 more

deployed with moduleid = TestEJB-war

WEB0100: Loading web module [TestEJB-war] in virtual server [server] at [/TestEJB-war]

moriaka at 2007-7-9 5:44:16 >

# 5

The ejb-ref mapping in sun-web.xml still doesn't match the target global JNDI name.

<jndi-name>corbaname:iiop:192.168.209.132:3700#ejb/TestRemote</jndi-name>

should be

<jndi-name>corbaname:iiop:192.168.209.132:3700#ejb.TestRemote</jndi-name>

Also, what version of the App Server are you using? There was a bug that prevented

this from working in the original Java EE 5 SDK.It should be fixed in the latest

release on the web site or from glassfish. Here's the bug :

https://glassfish.dev.java.net/issues/show_bug.cgi?id=735

ksaksa at 2007-7-9 5:44:16 >

# 6

Hey there.

I replaced the / with a . in the JNDI name.

I did not verify the version of my App Server since I work on a different computer today... I will confirm you the version in a future post.

What I did though is install a brand new version of Sun App Server on my remote machine (a debian linux virtual machine). If I run the command: "./asadmin version" I get 9.0_01.

On my local machine, I re-installed a new java EE SDK netbeans included, freshly downloaded from Sun. Same thing with "./asadmin version" I get 9.0_01.

Let me reconfirm the configuration:

Server

EJB on the server has the ejb.TestRemote JNDI name. It is deployed, I can telnet the 3700 port

Local

web.xml

<ejb-ref>

<ejb-ref-name>Test</ejb-ref-name>

<ejb-ref-type>Session</ejb-ref-type>

<home>ejb.TestLocal</home> //If it is not there, I can't deploy/run... !!! and netbeans gives me an error on the file

<remote>ejb.TestRemote</remote>

</ejb-ref>

sun-web.xml

<ejb-ref>

<ejb-ref-name>Test</ejb-ref-name>

<jndi-name>corbaname:iiop:10.211.55.7:3700#ejb.TestRemote</jndi-name>

</ejb-ref>

Servlet

try {

Context c = new InitialContext();

//return (TestRemote) c.lookup("ejb.TestRemote");//WORKING IF EJB & WAR ON SAME SERVER

return (TestRemote) c.lookup("java:comp/env/Test");

}

catch(NamingException ne) {

Logger.getLogger(getClass().getName()).log(Level.SEVERE,"exception caught" ,ne);

throw new RuntimeException(ne);

}

When I deploy on my local server I get the following errors:

App Server Output