EJB; Drawbacks of local interfaces?

Hi,
Would be appreciated if some body could tell me what are the drawbacks of local interfaces?
Thanks

There is nothing said as to whether or not the local interfaces are available to Servlets if the web container is running in the same JVM as the EJB container, or at least nothing I could find in the EJB 2.0 or J2EE 1.3 specifications.
I haven't taken the opportunity to find out, but my guess is that as long as the EJB local home entries are findable by the client code and the client code use the objects stored there, then it will work.
ANyone have any direct experience with this or better yet, additional insight into this question from a standards perspective.
Chuck

Similar Messages

EJB 3.0 local interface JNDI

Hello
I found some information that will probably help a lot of people having trouble with local interface not referenced in JNDI.
You need to delacre each local interface in the web.xml.
     <ejb-local-ref>
          <ejb-ref-name>MappedNameInYourEJB</ejb-ref-name>
          <ejb-ref-type>Session</ejb-ref-type>
<local> yourLocalInterface
          </local>
     </ejb-local-ref>
The weird thing about this is you don't need to do it when you use remote interface!! I would have thought Weblogic was smart enough to put your EJB in the JNDI when you declare @local on your interface!!
Am I wrong with something here?
When I read the EJB spec, it says you don't need to declare your EJB anywhere when you use annotation....
If someone have an explanation I would be very happy to read about it!!!!
Tanx

Hi,
In our current impl, we don't bind local business interface impl onto global jndi, this is because adding global JNDI binding for local EJB means every local business interface object must be bound into global JNDI, which will give rise to strange errors when accessing remotely or in different application context.
On the other hand, you needn't add each local interface in the web.xml, you can use annotation through EJB link, which is the suggested way to use EJB local reference, for example:
@Stateful(name="AccountManagementBean")
public class AccountManagementBean
@EJB(
name="PersonBeanRef",
beanName="PersonBean"
Person person;
@Stateless(name="PersonBean")
public class PersonBean implements Person {
In this example, AccountManagementBean has a local reference of PersonBean, the key is you should use beanName in @EJB, whose value is the ejb name of referenced EJB.

Accessing Local Interface EJB from Web Container Oracle App Server 9.0.4

Hi,
I am developing a struts based small application, which calls a EJB which uses Local Interface from Struts ActionClass.
I am getting NameNotFoundException. The exact exception is s mentioned below.
05/03/29 16:15:49 javax.naming.NameNotFoundException: LoginRSL not found
The deployment descriptors are as mentioned below.
=============
ejb-jar.xml
<?xml version = '1.0' encoding = 'windows-1252'?>
<!DOCTYPE ejb-jar PUBLIC "-//Sun Microsystems, Inc.//DTD Enterprise JavaBeans 2.0//EN" "http://java.sun.com/dtd/ejb-jar_2_0.dtd">
<ejb-jar>
<enterprise-beans>
<session>
<description>Session Bean ( Stateless )</description>
<display-name>LoginRSL</display-name>
<ejb-name>LoginRSL</ejb-name>
<local-home>loginApp.model.LoginRHome</local-home>
<local>loginApp.model.LoginL</local>
<ejb-class>loginApp.model.LoginRSL</ejb-class>
<session-type>Stateless</session-type>
<transaction-type>Container</transaction-type>
</session>
</enterprise-beans>
<relationships/>
<assembly-descriptor>
<container-transaction>
<method>
<ejb-name>LoginRSL</ejb-name>
<method-name>*</method-name>
</method>
<trans-attribute>Required</trans-attribute>
</container-transaction>
</assembly-descriptor>
</ejb-jar>
orion-ejb-jar.xml
<?xml version = '1.0' encoding = 'windows-1252'?>
<!DOCTYPE orion-ejb-jar PUBLIC "-//Evermind//DTD Enterprise JavaBeans 1.1 runtime//EN" "http://xmlns.oracle.com/ias/dtds/orion-ejb-jar.dtd">
<orion-ejb-jar>
<enterprise-beans>
<session-deployment name="LoginRSL"/>
</enterprise-beans>
</orion-ejb-jar>
I also tried adding following code to web.xml
web.xml
<ejb-local-ref>
<ejb-ref-name>LoginRSL</ejb-ref-name>
<ejb-ref-type>Session</ejb-ref-type>
<local-home>LoginRHome</local-home>
<local>LoginL</local>
<ejb-link>LoginRSL</ejb-link>
</ejb-local-ref>
It is quite evident that it is not able to lookup the JNDI name.
Can someone throw light on this? If someone has working sample of this, can you mail it to [email protected]?

Nipun,
WebLogic and OC4J are not the same thing. That's like saying Oracle and SQL Server are the same thing -- or C++ and Java are the same thing.
I recall a posting to a forum (don't remember if it was this one), where the poster was complaining that some feature of the application server he had previously used, was not supported by OC4J. Turned out that the feature he was referring to, contradicted the J2EE specification -- which is why it wasn't available in OC4J. In other words, he didn't like the fact that OC4J was more compliant with the J2EE specification than his "other" application server. Go figure!
So, if you haven't already done so, I suggest you verify that this feature of WebLogic is something that complies with the J2EE specifications -- before expecting OC4J to support the same feature.
And if it's not clear, from the specifications, then every vendor is free to implement this feature (or not).
So if it turns out that WebLogic is a more appropriate application server for you -- then why not just stick with it (and forget the others)?
Good Luck,
Avi.

Local Interfaces in WebLogic 7.0 Not Faster Than Remote Interfaces?

I was curious how much faster calling business methods in
a stateless session EJB in WebLogic 7.0 would be through
a local interface than calling the same business methods
through a remote interface. I timed both ways of calling
the same methods and much to my surprise the times were
nearly identical. I double-checked that in one case I really
used the local interface (using ejb-local-ref, local-jndi-name,
local interfaces in source code). Does anybody (perhaps from
BEA) have an explanation for this? By the way, I ran the
same experiment with other J2EE application servers such
as IBM's WebSphere 5 (Beta) and there was a tremendous
performance difference between local and remote interface
usage.
Thanks,
Reinhard

"Reinhard Klemm" <[email protected]> wrote in message
news:[email protected]...
I appreciate your response and, at the same time, I am somewhat
surprised about it. Here are the reasons for my surprise:
1. Your response indicates that WebLogic uses RMI for
EJB local method calls, i.e., even if the client is on the same VM.
I would have assumed that WebLogic would bypass RMI in such
a situation.That is not what I said. Local interfaces wont use rmi.
But remote interfaces do better if the call is from the same VM. This is
weblogic rmi optimization. Please see Rob's posting also.
2. Other J2EE application servers fare a lot better. In one
experiment, I timed WebLogic against WebSphere 5.0 Technology
for Developers (i.e., WebSphere 5.0 Beta, which is expressly
NOT for performance testing) and against the Sun Reference
Implementation. Here are the numbers for calling business
methods in a stateless session EJB through its local interface:
WebLogic: 5.15 ms on the average
WebSphere: 0.41 ms on the average
Sun Reference Implementation: 0.11 ms on the average
This indicates to me that both WebSphere and the Sun Reference
Implementation are better optimized than WebLogic by excluding
RMI when making local EJB calls.
Reinhard
"Maruthi Nuthikattu" <[email protected]> wrote in message
news:<[email protected]>...
Can you post some numbers so that we can visualize the difference.
Please add the numbers with other J2EE appserver also.
Otherwise top of my head, the reason is:
Weblogic rmi is well optimized for the calls with in the same JVM andsame
J2EE application.
This could be the reason you are not seeing much difference.
..maruthi
"Reinhard Klemm" <[email protected]> wrote in message
news:[email protected]...
I was curious how much faster calling business methods in
a stateless session EJB in WebLogic 7.0 would be through
a local interface than calling the same business methods
through a remote interface. I timed both ways of calling
the same methods and much to my surprise the times were
nearly identical. I double-checked that in one case I really
used the local interface (using ejb-local-ref, local-jndi-name,
local interfaces in source code). Does anybody (perhaps from
BEA) have an explanation for this? By the way, I ran the
same experiment with other J2EE application servers such
as IBM's WebSphere 5 (Beta) and there was a tremendous
performance difference between local and remote interface
usage.
Thanks,
Reinhard

Local interfaces and WLS 7

Hi *,
does anybody know if localinterfaces work in WLS7 SP1?
thanx,
Yauheni

Yes. my classes were inclueded in system CLASSPATH. but Sun spec says nothing about
that local interfaces could work only in the application context. it says that restriction
is that it could work only on the same JVM. so it looks very strange, isn't it? i
will try to pack everything in ear and try it again.
Thanx,
Yauheni
"Dimitri I. Rakitine" <[email protected]> wrote:
Yes, it looks like this is a problem. Your application used to work on 6
because you
added all your classes to the system classpath, right? And it sounds like
in 7, local
calls also depend on the application environment being set.
Yauheni Prykhodzka <[email protected]> wrote:
actually, may be that is the problem, we have no ear. we have a set ofjars with
ejbs and a set of web applications, whci are not packed in war. couldit be a problem,
when i use local interfaces?
but spec says that local interface could be used inside a JVM. i thinkit should
not play a role, if classloadres of ejb and component that use ejb aredifferent.
is it true?
Yauheni
"Dimitri I. Rakitine" <[email protected]> wrote:
Do you mean that servlet, which is a part of a .war which is deployed
in
the
same .ear with the EJB components fails to invoke EJB's using local interfaces?
Yauheni Prykhodzka <[email protected]> wrote:
"Dimitri I. Rakitine" <[email protected]> wrote:
Interesting. I guess that the problem will go away if you stop using
startup
classes
(for example, use load-on-startup servlet instead to perform initialization
steps).
No. I get the same problem after weblogic started. If i try to use localinterfaces
from another bean o servlet i get the same exception.
Yauheni
Yauheni Prykhodzka <[email protected]> wrote:
Here is the exception, which i'm getting:
<10.07.2002 11:43:55 CEST> <Emergency> <WebLogicServer> <000342> <Unableto init
ialize the server: Fatal initialization exception
Throwable: weblogic.t3.srvr.FatalStartupException: Can't start serverdue to sta
rtup class failure IdGeneratorStartUp - with nested exception:
[javax.naming.LinkException: [Root exception is javax.naming.NameNotFoundExcept
ion: remaining name: /app/ejb/dox.comp.IdGenerator.jar#IdGenerator/local-home];
Link Remaining Name: 'java:app/ejb/dox.comp.IdGenerator.jar#IdGenerator/local-ho
me']
javax.naming.LinkException: . Root exception is javax.naming.NameNotFoundExcept
ion: remaining name: /app/ejb/dox.comp.IdGenerator.jar#IdGenerator/local-home
<<no stack trace available>>
--------------- nested within: ------------------
weblogic.t3.srvr.FatalStartupException: Can't start server due to
startup
class
failure IdGeneratorStartUp - with nested exception:
[javax.naming.LinkException: [Root exception is javax.naming.NameNotFoundExcept
ion: remaining name: /app/ejb/dox.comp.IdGenerator.jar#IdGenerator/local-home];
Link Remaining Name: 'java:app/ejb/dox.comp.IdGenerator.jar#IdGenerator/local-ho
me']
at weblogic.t3.srvr.StartupClassRunner$1.run(StartupClassRunner.java:95)
at weblogic.security.service.SecurityServiceManager.runAs(SecurityServic
eManager.java:721)
at weblogic.t3.srvr.StartupClassRunner.run(StartupClassRunner.java:71)
at java.lang.Thread.run(Thread.java:484)
>
The WebLogic Server did not start up properly.
the JNDI name for local interface is IdGeneratorLocalHome. i use thisname for lookup.
Thanx,
Yauheni--
Dimitri--
Dimitri
Dimitri

Remote and local interface on same ejb 3.0 bean instance

Hi,
Is it posible to get remote and local interface on same ejb 3.0 bean instance.
For example get local interface of a bean and than pass it as remote to client.
Both interfaces must operate on same bean instance.
Thanks
Zlaja

yes. You can implement multiple interfaces on a single class, so you can add a local and a remote interface. One trick to avoid duplicate code is to simply make the remote interface extend the local interface; then you only have to add the @Remote annotation and you're done.
For example get local interface of a bean and than pass it as remote to client.You don't pass an instances to a client, a client looks up a remote instance of the bean through JNDI.

How can I get a reference to the Local interface of a EJB 3 session?

Hi,
How can I get a reference to the Local interface of a EJB 3 session?
My session implements both the local and remote interfaces, so in my client, when I look up the remote interface using the following code, I did get a reference
          processor = (IItemProcessorRemote)initialContext.lookup(IItemProcessorRemote.class.getName());but if I also look up the local interface in th eclient using this:
processorLocal =(IItemProcessor)initialContext.lookup(IItemProcessor.class.getName());I got errors like the following, do you know why? Thanks a lot!
Exception in thread "main" javax.naming.NameNotFoundException: sessions.IItemProcessor not found
     at com.sun.enterprise.naming.TransientContext.doLookup(TransientContext.java:203)
     at com.sun.enterprise.naming.TransientContext.lookup(TransientContext.java:175)
     at com.sun.enterprise.naming.SerialContextProviderImpl.lookup(SerialContextProviderImpl.java:61)
     at com.sun.enterprise.naming.RemoteSerialContextProviderImpl.lookup(RemoteSerialContextProviderImpl.java:116)
     at sun.reflect.GeneratedMethodAccessor114.invoke(Unknown Source)
     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
     at java.lang.reflect.Method.invoke(Method.java:597)
     at com.sun.corba.ee.impl.presentation.rmi.ReflectiveTie._invoke(ReflectiveTie.java:121)
     at com.sun.corba.ee.impl.protocol.CorbaServerRequestDispatcherImpl.dispatchToServant(CorbaServerRequestDispatcherImpl.java:650)
     at com.sun.corba.ee.impl.protocol.CorbaServerRequestDispatcherImpl.dispatch(CorbaServerRequestDispatcherImpl.java:193)
     at com.sun.corba.ee.impl.protocol.CorbaMessageMediatorImpl.handleRequestRequest(CorbaMessageMediatorImpl.java:1705)
     at com.sun.corba.ee.impl.protocol.CorbaMessageMediatorImpl.handleRequest(CorbaMessageMediatorImpl.java:1565)
     at com.sun.corba.ee.impl.protocol.CorbaMessageMediatorImpl.handleInput(CorbaMessageMediatorImpl.java:947)
     at com.sun.corba.ee.impl.protocol.giopmsgheaders.RequestMessage_1_2.callback(RequestMessage_1_2.java:178)
     at com.sun.corba.ee.impl.protocol.CorbaMessageMediatorImpl.handleRequest(CorbaMessageMediatorImpl.java:717)
     at com.sun.corba.ee.impl.transport.SocketOrChannelConnectionImpl.dispatch(SocketOrChannelConnectionImpl.java:473)
     at com.sun.corba.ee.impl.transport.SocketOrChannelConnectionImpl.doWork(SocketOrChannelConnectionImpl.java:1270)
     at com.sun.corba.ee.impl.orbutil.threadpool.ThreadPoolImpl$WorkerThread.run(ThreadPoolImpl.java:479)

BTW, findItemByTitle(String title) is a business method in my ItemProcessor session bean.
public String findItemByTitle(String title) {
          AuctionItem item;
          String result = null;
          try {
               Query query = entityManager
                         .createNativeQuery("SELECT i from AuctionItem i WHERE i.title LIKE : aTitle");
               query.setParameter("aTitle", title);
               item = (AuctionItem) query.getSingleResult();
               result = item.toString();
          } catch (EntityNotFoundException notFound) {
          } catch (NonUniqueResultException nonUnique) {
          return result;
     }

EJB 3.0 Session bean local interface NullPointerException

I am trying a very simple test of a Stateless EJB 3.0 bean called from a servlet.
The bean has a local interface, annotated with @Local. The bean implements that interface and is annotated with @Stateless.
I have a servlet with a variable of the local interface type, annotated with @EJB. The servlet's doGet method invokes the bean's one method using that interface and it works fine.
BUT if I put the same variable, annotated with @EJB into another class in the web container, it is not injected correctly and I get a NullPointerException on the variable. This class is in WEB-INF/classes with the servlet class, so I assume it is loaded by the same classloader.
I don't understand why the servlet can instantiate the EJB local interface successfully but another class in the web container can't. I get the same result in OC4J standalone 10.1.3.1 and 10.1.3.3.

Only managed classes like servlets, filters etc. will have context and EJB references injected into them, and only with servlet version 2.5. A work colleague found the answer in Debu Panda's blog:
http://debupanda.blogspot.com/2006_10_01_archive.html#116184543992078773
This behaviour appears to be part of the EJB 3.0 standard.
The solution is to use JNDI lookup in the client class (POJO) and declare an ejb-local-ref in web.xml.

EJB 3.0 Stateless Local Interface not found

Using Jdeveloper 1.3 it looked that EJB 3.0 local stateless session EJB bean cannot be found using ejection or lookup. It works with a remote interface.
Context context =new InitialContext();
SessionEJB sessionEJB = (SessionEJB)context.lookup("SessionEJB");
Is it a bug ?
Thank You

Using Jdeveloper 1.3 it looked that EJB 3.0 local stateless session EJB bean cannot be found using ejection or lookup. It works with a remote interface.
Context context =new InitialContext();
SessionEJB sessionEJB = (SessionEJB)context.lookup("SessionEJB");
Is it a bug ?
Thank You

Deploying EJB with Local Interfaces.

HI everybody
I am trying example on EJB with LocalInterfaces with BMP.
My bean without Local interface is deployed and working fine.
Then i have changed Home & Remote interface code. Again i have deployed it . It is deployed but i am unable to Look Up.
I am using J2SDKEE1.3 server & JDK1.3.
I have changed both interface files as follow:-
I have made my Home interface as :
public interface RetrieveConditionHome extends javax.ejb.EJBLocalHome {
     public RetrieveCondition create(String SQL_WHERE_ID, String SQL_WHERE_NAME,
          String FROM_TABLE , String WHERE_CLAUSE , String LAST_UPD_USER_ID ,
          Date LAST_UPD_TMSTMP, int ROW_VERSION)
          throws CreateException;
I have made my Remote interface as :
public interface RetrieveCondition extends javax.ejb.EJBLocalObject {
     public String getSQLWHERENAME() ;
-Viren

In JMS tutorial : They have stated ejbCreateLocal method.
I am not using this method in my Bean class. I am using general ejbCreate method as we normally do .
I am really confused about these methods : ejbCreate & ejbCreateLocal.
JMS Tutorial site (where they have used ejbCreateLocal):
A J2EETM Application that Uses the JMS API with an Entity Bean
java.sun.com/products/jms/tutorial/1_3-fcs/doc/j2eeapp3.html
Viren

Using local interfaces for EJB (session bean)

Hi,
I�ve a question regarding when to use the Local interfaces(EJBLocal and EJBLocalHome) of a enterprise bean. I understand that calls to enterprise bean can be made locally if the client which is invoking is in the same JVM as that of EJB. I�ve written a web client (servlet) which is packaged in a EAR and this servlet is trying to invoke a session bean which is in a �different� EAR using local interfaces. Both the EARs have been deployed in a single server (websphere 6.0 server). It didn�t work for me this way�..If I package the servlet in the same EAR of session bean then it works fine.
So is this to say that both EARs are not running on the same JVM? Or should it work even if the client and the session bean are in different EARs but in same server?
Can anyone explain me the fundamentals behind this.
Thanks in advance

Local access is only portable within the same .ear. For example, the Java EE SDK and SUN's
application servers have never supported local EJB access from a web/EJB component in a different
.ear. One issue is that local access requires that both the caller and target EJB have the same
classloader. By definition, different Java EE applications have distinct classloaders. In addition,
in Java EE 5 persistence context propagation does not span applications, so it wouldn't work in the
local case.
--ken

Questions about EJB local interfaces - 9iAS 9.03

Intro: I am new in developing EJB, and I am trying to build an example to verify that a stateless session bean with local interfaces is quite efficient.
Q1: I have read that an application trying to access local interfaces of an EJB must run into the same JVM. Does it means that it should be deployed into the same OC4J instance as the servlet?
Q2: I am using JDev 10g to build the EJB, with local and remote interfaces. Using the internal OC4J container, I can use the remote interfaces but not the internal one: an object of class "_Proxy1" is returned after the lookup (with the same name as given for the remote interface related call). Is it possible to access the local interface?
Q3: My application architecture is already defined to split the business logic in two EJBs: one stateless session bean for volatile data and one entity bean for a global user list cache. Where can I find a working example (with source code, please) to be deployed on 9iAS that can validate my design?
Q4: In many places, I read that CMP entity bean are easier to develop than BMP one. Is there any special consideration I should be aware of before implementing a CMP for my global user list cache?
Thanks a lot, Dom.

I have just read:
I think the problem is that local interfaces can only by
accessed through the same container, and JSP/Servlet's
one is different from EJB's one, regardless of you many
application server's instances do you have... Hope this
is the answer...Is there anyone who know if it applies too to 9iAS?
A+, Dom

EJB Local Interfaces / javax.naming.NamingException

Hi!
I have tried to deploy a very simple (Hello World like)EJB-Application. It contains a simple stateless SessionBean (with local interfaces) and a JSP which is using the EJB.
Opening the JSP i get the following error message:
javax.naming.NamingException: Error instantiating web-app JNDI-context: No location specified and no suitable instance found for the ejb-local-ref 'ejb/TesterEJB', an EJB matching it's ejb-link 'ejb-jar-ic.jar#TesterEJB' was found, but it contained an Entity, not a Session
Here's my ejb-jar.xml:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE ejb-jar PUBLIC '-//Sun Microsystems, Inc.//DTD Enterprise JavaBeans 2.0//EN' 'http://java.sun.com/dtd/ejb-jar_2_0.dtd'>
<ejb-jar>
     <display-name>oc4jJAR</display-name>
     <enterprise-beans>
          <session>
               <display-name>TesterEJB</display-name>
               <ejb-name>TesterEJB</ejb-name>
               <local-home>oc4jtest.TesterHome</local-home>
               <local>oc4jtest.Tester</local>
               <ejb-class>oc4jtest.TesterBean</ejb-class>
               <session-type>Stateless</session-type>
               <transaction-type>Container</transaction-type>
               <security-identity>
                    <description/>
                    <use-caller-identity/>
               </security-identity>
          </session>
     </enterprise-beans>
     <assembly-descriptor>
          <method-permission>
               <unchecked/>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>Local</method-intf>
                    <method-name>getMessage</method-name>
                    <method-params/>
               </method>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>Local</method-intf>
                    <method-name>getPrimaryKey</method-name>
                    <method-params/>
               </method>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>Local</method-intf>
                    <method-name>getEJBLocalHome</method-name>
                    <method-params/>
               </method>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>LocalHome</method-intf>
                    <method-name>remove</method-name>
                    <method-params>
                         <method-param>java.lang.Object</method-param>
                    </method-params>
               </method>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>Local</method-intf>
                    <method-name>remove</method-name>
                    <method-params/>
               </method>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>Local</method-intf>
                    <method-name>isIdentical</method-name>
                    <method-params>
                         <method-param>javax.ejb.EJBLocalObject</method-param>
                    </method-params>
               </method>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>LocalHome</method-intf>
                    <method-name>create</method-name>
                    <method-params/>
               </method>
          </method-permission>
          <container-transaction>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>Local</method-intf>
                    <method-name>getMessage</method-name>
                    <method-params/>
               </method>
               <trans-attribute>Required</trans-attribute>
          </container-transaction>
     </assembly-descriptor>
</ejb-jar>
And here's my web.xml:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE web-app PUBLIC '-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN' 'http://java.sun.com/dtd/web-app_2_3.dtd'>
<web-app>
     <display-name>oc4jWAR</display-name>
     <filter>
          <filter-name>TestFilter</filter-name>
          <display-name>TestFilter</display-name>
          <description/>
          <filter-class>oc4jtest.TestFilter</filter-class>
     </filter>
     <filter-mapping>
          <filter-name>TestFilter</filter-name>
          <url-pattern>*.jsp</url-pattern>
     </filter-mapping>
     <servlet>
          <servlet-name>test</servlet-name>
          <display-name>test</display-name>
          <jsp-file>/test.jsp</jsp-file>
     </servlet>
     <session-config>
          <session-timeout>30</session-timeout>
     </session-config>
     <welcome-file-list>
          <welcome-file>/test.jsp</welcome-file>
     </welcome-file-list>
     <ejb-local-ref>
          <ejb-ref-name>ejb/TesterEJB</ejb-ref-name>
          <ejb-ref-type>Session</ejb-ref-type>
          <local-home>oc4jtest.TesterHome</local-home>
          <local>oc4jtest.Tester</local>
          <ejb-link>ejb-jar-ic.jar#TesterEJB</ejb-link>
     </ejb-local-ref>
</web-app>
What's wrong?
Comments would be appreciated!
Thanks!
Peter
PS: The application runs fine on Sun's Reference Implementation!

Hi!
I have tried to deploy a very simple (Hello World like)EJB-Application. It contains a simple stateless SessionBean (with local interfaces) and a JSP which is using the EJB.
Opening the JSP i get the following error message:
javax.naming.NamingException: Error instantiating web-app JNDI-context: No location specified and no suitable instance found for the ejb-local-ref 'ejb/TesterEJB', an EJB matching it's ejb-link 'ejb-jar-ic.jar#TesterEJB' was found, but it contained an Entity, not a Session
Here's my ejb-jar.xml:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE ejb-jar PUBLIC '-//Sun Microsystems, Inc.//DTD Enterprise JavaBeans 2.0//EN' 'http://java.sun.com/dtd/ejb-jar_2_0.dtd'>
<ejb-jar>
     <display-name>oc4jJAR</display-name>
     <enterprise-beans>
          <session>
               <display-name>TesterEJB</display-name>
               <ejb-name>TesterEJB</ejb-name>
               <local-home>oc4jtest.TesterHome</local-home>
               <local>oc4jtest.Tester</local>
               <ejb-class>oc4jtest.TesterBean</ejb-class>
               <session-type>Stateless</session-type>
               <transaction-type>Container</transaction-type>
               <security-identity>
                    <description/>
                    <use-caller-identity/>
               </security-identity>
          </session>
     </enterprise-beans>
     <assembly-descriptor>
          <method-permission>
               <unchecked/>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>Local</method-intf>
                    <method-name>getMessage</method-name>
                    <method-params/>
               </method>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>Local</method-intf>
                    <method-name>getPrimaryKey</method-name>
                    <method-params/>
               </method>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>Local</method-intf>
                    <method-name>getEJBLocalHome</method-name>
                    <method-params/>
               </method>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>LocalHome</method-intf>
                    <method-name>remove</method-name>
                    <method-params>
                         <method-param>java.lang.Object</method-param>
                    </method-params>
               </method>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>Local</method-intf>
                    <method-name>remove</method-name>
                    <method-params/>
               </method>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>Local</method-intf>
                    <method-name>isIdentical</method-name>
                    <method-params>
                         <method-param>javax.ejb.EJBLocalObject</method-param>
                    </method-params>
               </method>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>LocalHome</method-intf>
                    <method-name>create</method-name>
                    <method-params/>
               </method>
          </method-permission>
          <container-transaction>
               <method>
                    <ejb-name>TesterEJB</ejb-name>
                    <method-intf>Local</method-intf>
                    <method-name>getMessage</method-name>
                    <method-params/>
               </method>
               <trans-attribute>Required</trans-attribute>
          </container-transaction>
     </assembly-descriptor>
</ejb-jar>
And here's my web.xml:
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE web-app PUBLIC '-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN' 'http://java.sun.com/dtd/web-app_2_3.dtd'>
<web-app>
     <display-name>oc4jWAR</display-name>
     <filter>
          <filter-name>TestFilter</filter-name>
          <display-name>TestFilter</display-name>
          <description/>
          <filter-class>oc4jtest.TestFilter</filter-class>
     </filter>
     <filter-mapping>
          <filter-name>TestFilter</filter-name>
          <url-pattern>*.jsp</url-pattern>
     </filter-mapping>
     <servlet>
          <servlet-name>test</servlet-name>
          <display-name>test</display-name>
          <jsp-file>/test.jsp</jsp-file>
     </servlet>
     <session-config>
          <session-timeout>30</session-timeout>
     </session-config>
     <welcome-file-list>
          <welcome-file>/test.jsp</welcome-file>
     </welcome-file-list>
     <ejb-local-ref>
          <ejb-ref-name>ejb/TesterEJB</ejb-ref-name>
          <ejb-ref-type>Session</ejb-ref-type>
          <local-home>oc4jtest.TesterHome</local-home>
          <local>oc4jtest.Tester</local>
          <ejb-link>ejb-jar-ic.jar#TesterEJB</ejb-link>
     </ejb-local-ref>
</web-app>
What's wrong?
Comments would be appreciated!
Thanks!
Peter
PS: The application runs fine on Sun's Reference Implementation!

EJB Local Interfaces

My understanding is that the concept of local interfaces (i.e.
direct invocation in lieu of an IPC) exist in EJB 2.0. Does
OC4J support this today? If not, will there be support for it
in 9i AS 2.0?
Thanks.

oc4j/orion supports ejb 2.0 as it stood in the second draft.
There have been many changes since then, including dropping DO's
and using Local Interfaces instead.
OC4J/Orion will have a new version by the end of this year or
early next year which will implement ejb 2.0.
Until then, if you want the speed you would get with local
interfaces in oc4j/orion, you can modify your orion-ejb-jar.xml
to use copy-by-value="false". This will give you the same
performance gain as using local interfaces. Its a hack, but what
the heck, it works.
Regards,
the elephantwalker
www.elephantwalker.com

How local interfaces work in EJBs

How exactly local interfaces work in EJBs and how should I use them ?
Thank you.

They are simply non-RMI interface implementations that directly delgate to the EJB's implementation. They are called and in turn call the EJB just as you would call any normal class.
As such, there is no RMI or serialization overhead and the interfaces can include methods that update their arguments, something not possible in remote interfaces.
Generally speaking, you should define local interfaces for all entities as one seldom if ever would access entities remotely. You might even consider defining ONLY local interfaces for entities, but that is a tougher call.
You would define local interfaces for session EJB's that are invoked by other session EJB's within the same container. I would normally always define both local and remote interfaces unless there is some reason why I can eliminate one or the other.
Chuck

EJB; Drawbacks of local interfaces?

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