Lookup of CMP Bean from client

After Deploying the CMP Bean from jdeveloper, the client is unable to lookup the Bean using the JNDI name. It gives unknown URL. All the libraries are added to the client.

Hi Zoongu,
Please look into the server.log for the actual exception message (and the stack trace).
You can call a CMP from a remote application client, but keep in mind that each and every method invocation will happen in a new transaction (there is no transaction
propagation between an app client and a server). It's a much better practice to access
a Session bean from the client (once) to perform all operations in the same transaction.
regards,
-marina

Similar Messages

How can i lookup a session bean from the client side

how can i lookup a session bean from the client side...........i am using sun appserver..............
this is my code.................[B]
private final static String JNDI_NAME="ejb/LmsBean";
private static String url="ldap://localhost:4848";
Hashtable h=new Hashtable();
h.put(Context.INITIAL_CONTEXT_FACTORY,"com.sun.jndi.ldap.LdapCtxFactory");
h.put(Context.PROVIDER_URL,url);
System.out.println("Before Loading Context in Delegate");
Context ctx=new InitialContext(h);
System.out.println("Loaded Context in Delegate");
Object obj=ctx.lookup(JNDI_NAME);
System.out.println("Loaded Object in Delegate");
System.out.println("Before Loading Home in Delegate");
LmsHome home = (LmsHome )PortableRemoteObject.narrow(obj,com.parx.lms.controller.LmsHome.class);
System.out.println("Loaded Home in Delegate");
lms = home.create();
System.out.println("Loaded remote in Delegate");
[B]and i got the exception........
Inside Client before calling delegate
Before Loading Context in Delegate
javax.naming.CommunicationException: Request: 1 cancelled
javax.naming.CommunicationException: Request: 1 cancelled
at com.sun.jndi.ldap.LdapRequest.getReplyBer(LdapRequest.java:60)
at com.sun.jndi.ldap.Connection.readReply(Connection.java:405)
at com.sun.jndi.ldap.LdapClient.ldapBind(LdapClient.java:340)
at com.sun.jndi.ldap.LdapClient.authenticate(LdapClient.java:171)
at com.sun.jndi.ldap.LdapCtx.connect(LdapCtx.java:2640)
at com.sun.jndi.ldap.LdapCtx.<init>(LdapCtx.java:290)
at com.sun.jndi.ldap.LdapCtxFactory.getUsingURL(LdapCtxFactory.java:175)
at com.sun.jndi.ldap.LdapCtxFactory.getUsingURLs(LdapCtxFactory.java:193
at com.sun.jndi.ldap.LdapCtxFactory.getLdapCtxInstance(LdapCtxFactory.ja
va:136)
at com.sun.jndi.ldap.LdapCtxFactory.getInitialContext(LdapCtxFactory.jav
a:66)
at javax.naming.spi.NamingManager.getInitialContext(NamingManager.java:6
62)
at javax.naming.InitialContext.getDefaultInitCtx(InitialContext.java:243
at javax.naming.InitialContext.init(InitialContext.java:219)
at javax.naming.InitialContext.<init>(InitialContext.java:195)
at com.parx.lms.lmsdelegate.LmsDelegate.getController(LmsDelegate.java:3
0)
at com.parx.lms.lmsdelegate.LmsDelegate.addUserDelegate(LmsDelegate.java
:50)
at com.parx.lms.client.consoleClient.Client.main(Unknown Source)
pls go tru the exception and pls help.........

That url string should be having the server name or ip instead of localhost.

How call session bean from Client side

Hi
calling session bean from client side it gives Lookup erroe, it gives JNDI error
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null

If you can make a connection using sess_sh, then you know that you have configured your database and listener properly. If it is not working, read the manuals that you can download from technet. They are pretty good, and if you follow the directions, you should see success.
Good Luck!
Brad

CMP Beans from Tables: Why does the Container try to create new tables?

I'm trying to develop an EJB application using JDeveloper on 9iAS. I have several CMPs and have my tables that I want my CMPs to be based on already defined in my DB schema. I want to use CMP but I don't want the Container to create the tables, rather I want the Container to map my CMP EJBs to the already existing tables.
The issue is:
While creating these CMP EJBs in JDeveloper I chose the "New Enterprise Java Bean" EJB creation wizard using the option labeled "Container-managed Entity Beans from Tables". My assumption is that this does what I want, because the wizard prompts for a schema and table you want to map to. Then it creates the attributes & getter/setter methods, PK class, etc. all based on the table defintion automatically. Great. So why when I try to run my application do I get error messages for each EJB such as:
Auto-creating table: create table STREET_TYPE (PK_STYP_ID NUMBER(8), STREET_TYPE VARCHAR2(20), primary key (PK_STYP_ID, STREET_TYPE))
Warning: Error creating table: ORA-00955: name is already used by an existing object
Huh?? I thought the idea is that the CMP EJB is mapped to the existing table in my schema. Why is the Container trying to create new tables?? Is this possible? Or am I missing something fundamental about how Containers create and manage CMPs? Or is this just a JDevelop container issue? TIA

I presume you are getting the problem on application
deploy? This happens when upon initialization of the application using the built-in OC4J container/app server that is part of JDeveloper. Here is the full messaging:
[Starting OC4J using the following ports: HTTP=8989, RMI=23892, JMS=9228.]
C:\OraHome1\jdk\bin\javaw.exe -ojvm -classpath C:\OraHome1\j2ee\home\oc4j.jar com.evermind.server.OC4JServer -config C:\OraHome1\jdev\system\oc4j-config\server.xml
[waiting for the server to complete its initialization...]
Copying default deployment descriptor from archive at Q:\CBTCOF\COF_APPLICATION\COF_Project\classes/META-INF/orion-ejb-jar.xml to deployment directory C:\OraHome1\jdev\system\oc4j-config\application-deployments\current-workspace-app\classes...
Auto-deploying file:/Q:/CBTCOF/COF_APPLICATION/COF_Project/classes/ (No previous deployment found)...
Auto-creating table: create table STREET_TYPE (PK_STYP_ID NUMBER(8), STREET_TYPE VARCHAR2(20), primary key (PK_STYP_ID, STREET_TYPE))
Warning: Error creating table: ORA-00955: name is already used by an existing object
[...OTHER SIMILAR ERROR MESSAGES]
done.
Oracle9iAS (9.0.2.0.0) Containers for J2EE initialized
If so, in the application.xml file of you
OC4J instance the is a setting autocreate-tables,
which by default is true!
Set it to false as below and that should clear up
your problem.
<orion-application autocreate-tables="false"
default-data-Hmm. I found at least a dozen or so files with that name and set everyone that had this attriute to "false", restarted the OC4J server and still got these errors.

Exception while i m looking up my session bean from Client

hi,
actully i try to make a simple session bean ok
first i make a seession bean and make his deployment discriptor
and put all thing a jar file and deployee this file on Server its successfuly
loaded and deploed.
ok the problem is when i make a client bean and try to run it. it give me this exception
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
at javax.naming.spi.NamingManager.getInitialContext(NamingManager.java:643)
at javax.naming.InitialContext.getDefaultInitCtx(InitialContext.java:246)
at javax.naming.InitialContext.getURLOrDefaultInitCtx(InitialContext.java:283)
at javax.naming.InitialContext.lookup(InitialContext.java:350)
at HelloClient.main(HelloClient.java:15)
Process Exit...
i where i right the machine name where my appserver is runing. inside lookup method
client bean code is
=====================
import java.rmi.*;
import javax.naming.*;
import java.util.*;
import HASSSAN.*;
public class HelloClient {
     public static void main(String arg[]) {
     try {
          javax.naming.Context ctx =
          new javax.naming.InitialContext(System.getProperties());
          Object obj = ctx.lookup("HelloBean");
          HelloHome home = (HelloHome) javax.rmi.PortableRemoteObject.narrow(obj,HelloHome.class);
          Hello hello =home.create();
          System.out.println(hello.sayHello());
          hello.remove();
          System.out.println("Success");
     }catch(Exception e) {
          e.printStackTrace();
}

Two hints:
Need to specify class name in environment or system
property, or as an applet parameter,
          javax.naming.Context ctx = new javax.naming.InitialContext(System.getProperties());This means you need to check what you're putting on your command line in the way of "-D" settings.
or in an application resource file:You can get this from the methodology jgongo mentions.

Cmp beans generated from rose

hi all;
i have a uml diagram with two classes (matser-detail). i generated the corresponding tables into oracle 9i database from rational rose.
using jdeveloper. when create cmp beans from this two tables, i deploy it works fine
but when i add my finder method (findByID) in ejbql i wrote:
select object(e) from employees e where e.employee_id=?1
i try to deploy again and i have the following error:
javax.ejb.EJBException: nested exception is: java.lang.StringIndexOutOfBoundsException: String index out of range: -1
java.lang.StringIndexOutOfBoundsException: String index out of range: -1
     at java.lang.String.substring(String.java:1525)
     at com.sun.ejb.sqlgen.SQLGenerator.generateCreateTableQuery(SQLGenerator.java:530)
     at com.sun.ejb.sqlgen.SQLGenerator.<init>(SQLGenerator.java:240)
     at com.sun.ejb.sqlgen.SQLGenerator.generateSQL(SQLGenerator.java:360)
     at com.sun.ejb.sqlgen.SQLGenerator.generateSQL(SQLGenerator.java:309)
     at com.evermind.server.ejb.deployment.EJBPackage.translateEjbqlQeries(EJBPackage.java:2100)
     at com.evermind.server.ejb.compilation.Compilation.translateEjbqlQeries(Compilation.java:140)
     at com.evermind.server.ejb.compilation.Compilation.compile(Compilation.java:178)
     at com.evermind.server.administration.ServerApplicationInstallation.finish(ServerApplicationInstallation.java:526)
     at java.lang.reflect.Method.invoke(Native Method)
     at com.evermind.server.rmi.RMICallHandler.run(RMICallHandler.java:119)
     at com.evermind.server.rmi.RMICallHandler.run(RMICallHandler.java:48)
     at EDU.oswego.cs.dl.util.concurrent.PooledExecutor$Worker.run(PooledExecutor.java:803)
     at java.lang.Thread.run(Thread.java:484)
javax.ejb.EJBException: nested exception is: java.lang.StringIndexOutOfBoundsException: String index out of range: -1
     at com.sun.ejb.sqlgen.SQLGenerator.<init>(SQLGenerator.java:255)
     at com.sun.ejb.sqlgen.SQLGenerator.generateSQL(SQLGenerator.java:360)
     at com.sun.ejb.sqlgen.SQLGenerator.generateSQL(SQLGenerator.java:309)
     at com.evermind.server.ejb.deployment.EJBPackage.translateEjbqlQeries(EJBPackage.java:2100)
     at com.evermind.server.ejb.compilation.Compilation.translateEjbqlQeries(Compilation.java:140)
     at com.evermind.server.ejb.compilation.Compilation.compile(Compilation.java:178)
     at com.evermind.server.administration.ServerApplicationInstallation.finish(ServerApplicationInstallation.java:526)
     at java.lang.reflect.Method.invoke(Native Method)
     at com.evermind.server.rmi.RMICallHandler.run(RMICallHandler.java:119)
     at com.evermind.server.rmi.RMICallHandler.run(RMICallHandler.java:48)
     at EDU.oswego.cs.dl.util.concurrent.PooledExecutor$Worker.run(PooledExecutor.java:803)
     at java.lang.Thread.run(Thread.java:484)
com.evermind.compiler.CompilationException: Error translating EJBQL: javax.ejb.EJBException: nested exception is: java.lang.StringIndexOutOfBoundsException: String index out of range: -1
     at com.evermind.server.ejb.compilation.Compilation.translateEjbqlQeries(Compilation.java:143)
     at com.evermind.server.ejb.compilation.Compilation.compile(Compilation.java:178)
     at com.evermind.server.administration.ServerApplicationInstallation.finish(ServerApplicationInstallation.java:526)
     at java.lang.reflect.Method.invoke(Native Method)
     at com.evermind.server.rmi.RMICallHandler.run(RMICallHandler.java:119)
     at com.evermind.server.rmi.RMICallHandler.run(RMICallHandler.java:48)
     at EDU.oswego.cs.dl.util.concurrent.PooledExecutor$Worker.run(PooledExecutor.java:803)
     at java.lang.Thread.run(Thread.java:484)
nb: when i use the HR schema coming with 9i it works fine.
need help

I presume you are getting the problem on application
deploy? This happens when upon initialization of the application using the built-in OC4J container/app server that is part of JDeveloper. Here is the full messaging:
[Starting OC4J using the following ports: HTTP=8989, RMI=23892, JMS=9228.]
C:\OraHome1\jdk\bin\javaw.exe -ojvm -classpath C:\OraHome1\j2ee\home\oc4j.jar com.evermind.server.OC4JServer -config C:\OraHome1\jdev\system\oc4j-config\server.xml
[waiting for the server to complete its initialization...]
Copying default deployment descriptor from archive at Q:\CBTCOF\COF_APPLICATION\COF_Project\classes/META-INF/orion-ejb-jar.xml to deployment directory C:\OraHome1\jdev\system\oc4j-config\application-deployments\current-workspace-app\classes...
Auto-deploying file:/Q:/CBTCOF/COF_APPLICATION/COF_Project/classes/ (No previous deployment found)...
Auto-creating table: create table STREET_TYPE (PK_STYP_ID NUMBER(8), STREET_TYPE VARCHAR2(20), primary key (PK_STYP_ID, STREET_TYPE))
Warning: Error creating table: ORA-00955: name is already used by an existing object
[...OTHER SIMILAR ERROR MESSAGES]
done.
Oracle9iAS (9.0.2.0.0) Containers for J2EE initialized
If so, in the application.xml file of you
OC4J instance the is a setting autocreate-tables,
which by default is true!
Set it to false as below and that should clear up
your problem.
<orion-application autocreate-tables="false"
default-data-Hmm. I found at least a dozen or so files with that name and set everyone that had this attriute to "false", restarted the OC4J server and still got these errors.

Why only j2sdkee1.3 support JNDI lookup "java:comp/env" from remote client?

Hi:
I have been puzzled by this function of j2sdkee1.3.1 support JNDI lookup "java:comp/env" from client. I always think that "java:comp/env" namespace can only be access by the application server self for it is a private namespace. The weblogic and websphere doest support this.
Why?
Regards!
John Lee

Hi:I'm unable to get JNDI reference object from remote application client with "java:comp/env/ejb/<lookupName>".
The exception says:
Application threw an exception:javax.naming.CommunicationException: Cannot connect to ORB [Root exception is org.omg.CORBA.COMM_FAILURE: vmcid: SUN minor code: 201 completed: No]
The J2EE server and client are run on different machines, and needs to be like this. There isn't any problem with JSP/Servlet (cause they run/execute on the server itself). How will the client find out the JNDI refernce my mere specification of "java:comp/env/..."?
Am I making a mistake anywhere?
BEA Weblogic & IBM Websphere allows explicitly specifying the server name, while doing JNDI lookup. Is there anything similary for J2EE?
I couldn't find reference for this anywhere in the J2EE tutorial or EJB books.
- Devashish

Why j2sdkee1.3.1 support JNDI lookup "java:comp/env" from remote client?

Hi:
I have been puzzled by this function of j2sdkee1.3.1 support JNDI lookup "java:comp/env"
from client. I always think that "java:comp/env" namespace can only be access
by the application server self for it is a private namespace. The weblogic and
websphere doest support this.
Why?
Regards!
John

Hi:I'm unable to get JNDI reference object from remote application client with "java:comp/env/ejb/<lookupName>".
The exception says:
Application threw an exception:javax.naming.CommunicationException: Cannot connect to ORB [Root exception is org.omg.CORBA.COMM_FAILURE: vmcid: SUN minor code: 201 completed: No]
The J2EE server and client are run on different machines, and needs to be like this. There isn't any problem with JSP/Servlet (cause they run/execute on the server itself). How will the client find out the JNDI refernce my mere specification of "java:comp/env/..."?
Am I making a mistake anywhere?
BEA Weblogic & IBM Websphere allows explicitly specifying the server name, while doing JNDI lookup. Is there anything similary for J2EE?
I couldn't find reference for this anywhere in the J2EE tutorial or EJB books.
- Devashish

HOW TO GET THE SQLEXCEPTION FROM CMP BEAN

Hi All,
I am using CMP Bean as back end in my application.My client class access the CMP Bean to Create or Update the records via Session Facade.In My Database i am using trigger to avoid the concurrent updation.So when the concurrent calls made the database triigger will throw ERROR ..It works fine....But in EJB all the Exception will be thrown as RemoteException.
But my problem is container will always throws Remote Exception to the client .I need get the actual SQL EXCEPTION (SQL STATE)thrown from the database.I have used the printStackTrace() method to print it in my Console..It work fine..I need to covert this as String ..So that only i can compare the String and can tell the End User what is the Error.....
when i convert this exception as String by Using the following Code -
Client.Java
try {
///I am calling the CMP Bean here via Session Facade
} catch (RemoteException e) {
String actualExc = null;
StringWritter sw = new StringWriter();
PrintWriter pw = new PrintWriter(sw);
e.printStackTrace(pw); //This call prints the exception in console
actualExc = sw.toString();///This string returns only the Stack levels classes ..Not the Exception.(I NEED THE FULL EXCEPTION DETAILS TO THIS STRING )
How to convert this printStackTrace() exception into String ......Please if u need any other details i will give u..Any idea about this..
Please reply me....

Thanks for the reply. Is there any other way to get the actual exception thrown from the database level in CMP bean. Because i am getting only the RemoteException in Client. I am Using Whepshere/DB2.

While connecting from Client to EJB , LookUp Error is Comming...

Hi All
I am working with Oracle Application Server 10g.
Here I downloaded one helloworld session bean from oracle site.
I am able to deploy .ear file.
But when I am connecting bean using client...
I am getting following error:
D:\helloworld>ant run
Buildfile: build.xml
init:
setup:
cli-classes:
[javac] Compiling 1 source file to D:\helloworld\build\helloworld\helloworld-client
cli-descriptor:
cli-jar:
[jar] Building jar: D:\helloworld\dist\helloworld-client.jar
run:
[java] client started...
[java] java.lang.InstantiationException: Error communicating with server: Lookup error: java.net.ConnectException: Connection refused: connect; nested exception is:
[java] java.net.ConnectException: Connection refused: connect; nested exception is:
[java] javax.naming.NamingException: Lookup error: java.net.ConnectException: Connection refused: connect; nested exception is:
[java] java.net.ConnectException: Connection refused: connect [Root exception is java.net.ConnectException: Connection refused: connect]
[java] at com.evermind.server.ApplicationClientContext.createContext(ApplicationClientContext.java:63)
[java] at com.evermind.server.ApplicationClientInitialContextFactory.getInitialContext(ApplicationClientInitialContextFactory.java:145)
[java] at javax.naming.spi.NamingManager.getInitialContext(NamingManager.java:662)
[java] at javax.naming.InitialContext.getDefaultInitCtx(InitialContext.java:243)
[java] at javax.naming.InitialContext.init(InitialContext.java:219)
[java] at javax.naming.InitialContext.<init>(InitialContext.java:175)
[java] at hello.HelloClient.main(HelloClient.java:25)
[java] NamingException: Error reading application-client descriptor: Error communicating with server: Lookup error: java.net.ConnectException: Connection refused: connect; nested exception is:
[java] java.net.ConnectException: Connection refused: connect; nested exception is:
[java] javax.naming.NamingException: Lookup error: java.net.ConnectException: Connection refused: connect; nested exception is:
[java] java.net.ConnectException: Connection refused: connect [Root exception is java.net.ConnectException: Connection refused: connect]
I used the following JNDI Configurations:
java.naming.factory.initial=com.evermind.server.ApplicationClientInitialContextFactory
java.naming.provider.url=ormi://localhost:23791/helloworld
Pls Post your results....
With Regards
Kumar

Try this:
java.naming.factory.initial=oracle.j2ee.rmi.RMIInitialContextFactory

Problem deploying cmp bean invoking another cmp bean using jndi lookup

I have a cmp BeanA that invokes another cmp BeanB, so I am using a jndi lookup in BeanA to download the localhome object to BeanB using the following:
Context ctx = new InitialContext();
home = (LocalAddressHome) ctx.lookup("java:comp/env/ejb/BeanBHomeRef");
then I specify the ejb/BeanBHomeRef, entity bean, local, BeanB's local home and component interface in EJB ref. when I am packaging BeanA
I also package BeanB in a separate jar file.
When I attempt to deploy the application it throws strange exception that says the folowing:
java.lang.IllegalArgumentException: BeanBEJB says it links to an ejb called BeanBEJB of local home class LocalBeanBHome but no bean with this local home c
lassname and type can be found in this ejb-jar.
yet when I un-jar the package, these class files exitsts.
When I go ahead and delete the reference to BeanB from the BeanA package file, I am able to deploy the application but then correctly fails on jndi lookup.
I have been able to open the cmpcustomer.ear sample application that comes with RI and execute it without any problem. But when I to package the same beans for example CustomerBean and it won't even allow me to create the customer.jar file. I get a screen full of errors.......
I am using Sun RI 1.3.01, is there a known bug that I am not aware of? Is there a fix around it?
Is there any another way to get the home ref. to BeanB so I can invoke create() method?
Any advice or suggestions?
thanksl
-kaisaab

What app server are you using? may be I can help you
--Ashish Saraf

Accessing the same stateful session bean from multiple clients in a clustered environment

I am trying to access the same stateful session bean from multiple
          clients. I also want this bean to have failover support so we want to
          deploy it in a cluster. The following description is how we have tried
          to solve this problem, but it does not seem to be working. Any
          insight would be greatly appreciated!
          I have set up a cluster of three servers. I deployed a stateful
          session bean with in memory replication across the cluster. A client
          obtains a reference to an instance of one of these beans to handle a
          request. Subsequent requests will have to use the same bean and could
          come from various clients. So after using the bean the first client
          stores the handle to the bean (actually the replica aware stub) to be
          used by other clients to be able to obtain the bean. When another
          client retrieves the handle gets the replica aware stub and makes a
          call to the bean the request seems to unpredictably go to any of the
          three servers rather than the primary server hosting that bean. If the
          call goes to the primary server everything seems to work fine the
          session data is available and it gets backed up on the secondary
          server. If it happens to go to the secondary server a bean that has
          the correct session data services the request but gives the error
          <Failed to update the secondary copy of a stateful session bean from
          home:ejb20-statefulSession-TraderHome>. Then any subsequent requests
          to the primary server will not reflect changes made on the secondary
          and vice versa. If the request happens to go to the third server that
          is not hosting an instance of that bean then the client receives an
          error that the bean was not available. From my understanding I thought
          the replica aware stub would know which server is the primary host for
          that bean and send the request there.
          Thanks in advance,
          Justin


          If 'allow-concurrent-call' does exactly what you need, then you don't have a problem,
          do you?
          Except of course if you switch ejb containers. Oh well.
          Mike
          "FBenvadi" <[email protected]> wrote:
          >I've got the same problem.
          >I understand from you that concurrent access to a stateful session bean
          >is
          >not allowed but there is a
          >token is weblogic-ejb-jar.xml that is called 'allow-concurrent-call'
          >that
          >does exactly what I need.
          >What you mean 'you'll get a surprise when you go to production' ?
          >I need to understand becouse I can still change the design.
          >Thanks Francesco
          >[email protected]
          >
          >"Mike Reiche" <[email protected]> wrote in message
          >news:[email protected]...
          >>
          >> Get the fix immediately from BEA and test it. It would be a shame to
          >wait
          >until
          >> December only to get a fix - that doesn't work.
          >>
          >> As for stateful session bean use - just remember that concurrent access
          >to
          >a stateful
          >> session bean is not allowed. Things will work fine until you go to
          >production
          >> and encounter some real load - then you will get a surprise.
          >>
          >> Mike
          >>
          >> [email protected] (Justin Meyer) wrote:
          >> >I just heard back from WebLogic Tech Support and they have confirmed
          >> >that this is a bug. Here is their reply:
          >> >
          >> >There is some problem in failover of stateful session beans when its
          >> >run from a java client.However, it is fixed now.
          >> >
          >> >The fix will be in SP2 which will be out by december.
          >> >
          >> >
          >> >Mike,
          >> >Thanks for your reply. I do infact believe we are correctly using
          >a
          >> >stateful session bean however it may have been misleading from my
          >> >description of the problem. We are not accessing the bean
          >> >concurrently from 2 different clients. The second client will only
          >> >come into play if the first client fails. In this case we want to
          >be
          >> >able to reacquire the handle to our stateful session bean and call
          >it
          >> >from the secondary client.
          >> >
          >> >
          >> >Justin
          >> >
          >> >"Mike Reiche" <[email protected]> wrote in message
          >news:<[email protected]>...
          >> >> You should be using an entity bean, not a stateful session bean
          >for
          >> >this application.
          >> >>
          >> >> A stateful session bean is intended to be keep state (stateful)
          >for
          >> >the duration
          >> >> of a client's session (session).
          >> >>
          >> >> It is not meant to be shared by different clients - in fact, if
          >you
          >> >attempt to
          >> >> access the same stateful session bean concurrently - it will throw
          >> >an exception.
          >> >>
          >> >> We did your little trick (storing/retrieving handle) with a stateful
          >> >session bean
          >> >> on WLS 5.1 - and it did work properly - not as you describe. Our
          >sfsb's
          >> >were not
          >> >> replicated as yours are.
          >> >>
          >> >> Mike
          >> >>
          >> >> [email protected] (Justin Meyer) wrote:
          >> >> >I am trying to access the same stateful session bean from multiple
          >> >> >clients. I also want this bean to have failover support so we want
          >> >to
          >> >> >deploy it in a cluster. The following description is how we have
          >tried
          >> >> >to solve this problem, but it does not seem to be working. Any
          >> >> >insight would be greatly appreciated!
          >> >> >
          >> >> >I have set up a cluster of three servers. I deployed a stateful
          >> >> >session bean with in memory replication across the cluster. A client
          >> >> >obtains a reference to an instance of one of these beans to handle
          >> >a
          >> >> >request. Subsequent requests will have to use the same bean and
          >could
          >> >> >come from various clients. So after using the bean the first client
          >> >> >stores the handle to the bean (actually the replica aware stub)
          >to
          >> >be
          >> >> >used by other clients to be able to obtain the bean. When another
          >> >> >client retrieves the handle gets the replica aware stub and makes
          >> >a
          >> >> >call to the bean the request seems to unpredictably go to any of
          >the
          >> >> >three servers rather than the primary server hosting that bean.
          >If
          >> >the
          >> >> >call goes to the primary server everything seems to work fine the
          >> >> >session data is available and it gets backed up on the secondary
          >> >> >server. If it happens to go to the secondary server a bean that
          >has
          >> >> >the correct session data services the request but gives the error
          >> >> ><Failed to update the secondary copy of a stateful session bean
          >from
          >> >> >home:ejb20-statefulSession-TraderHome>. Then any subsequent requests
          >> >> >to the primary server will not reflect changes made on the secondary
          >> >> >and vice versa. If the request happens to go to the third server
          >that
          >> >> >is not hosting an instance of that bean then the client receives
          >an
          >> >> >error that the bean was not available. From my understanding I
          >thought
          >> >> >the replica aware stub would know which server is the primary host
          >> >for
          >> >> >that bean and send the request there.
          >> >> >
          >> >> >Thanks in advance,
          >> >> >Justin
          >>
          >
          >

EJB 3.0: CMP Entity bean from view

Hi,
I have created an entity bean from a database view.
I don't have a good filed to use as id in my view. So I want to generate the id in my entity bean.
How can I do this ?
Thanks

Hi,
I didn't get your question.
CMP is something, which can be done by hand.
So maybe it is better, to do it manually.
Bea has some workaround, I am sure.
Maybe it is something with deployment descriptors, which
have to be configured to the underlying database.
Sorry for my stupid first answer.
Volker.

CMP Entity Bean from dataBase views

Hi forum,
I Have to migrate an existing application to JEE (with EJB3).
In this application there are a lot of dataBase views.
I'm new in EJB3 and I don't know how to structure cleanly entity beans (Specially when it are created from dataBase views).
My problem is that for each query made from the same dataBase view I almost have to create a new entity bean with a different @Id.
What can I do to to avoid it?
I had thought to genrate a new @Id (attribute not persistent) but I think is not possible. It's right ?
Someone can help me ?
Thanks

"CMP provides you with database independence and less coding efforts."
BMP is not database dependent, unless you invoke database specific things in your SQL (something I do not do). CMP on the otherhand is inherently appserver specific (which was it's goal when BEA, IBM, et al. came up with it), and still limits your design possibilities. See this thread for an example:
http://forum.java.sun.com/thread.jsp?forum=13&thread=318785
As for less coding effort, that is a relative statment. Yes a simple CMP bean requires less coding to develop the first time. I personally view a few lines of SQL to load and store the data as being fairly trivial. But that needs to be offset with the problems inherent in using appserver specific CMP implementations.
As an example, try mapping WebSphere CMP to a pre-existing database without using IBM's IDE. It's an incredible pain in the ass since WebSphere does not come with a "meet-in-the-middle" solution. Any J2EE developer that has had the experience of working with different appservers (especially if they have had to port an app, as I have) can attest to the complications that arise with each implementation.
A BMP bean, written with non-DB-specific SQL, is the most portable, most flexible approach to EntityBeans. Yes, it requires the developer to be able to write some SQL, which should not take a significant amout of time. WRT queries, you have to write them, either SQL, EQL, or some appserver specific format.
As an aside, the use of code generators to simplify the creation of EJBs lends itself well to BMP. By using a (or writing your own) code generator, you can mitigate the annoying SQL bugs that creep up early in development.

Can we run java bean from forms client server??

Hi,
The OLTP application we are planning to build has lot of gui e.g
tabs, drag and drop etc. Our aim is to make it web enabled but
the network bandwidth available is small 16 - 64K . So even
thoughwe plan toi use applet , we seriuosly doubt how good it
will perform on such low network bandwidth. [The system will
have 100 users]
Q1. What will be a reasonable bandwidth to run an oltp
application (say maintenance )
Hence we are thinking of developing with developer 6i and
deploying our application in client server mode, which can
easily be web enabled in future. But we also have to integrate
visual interfaces like gantt chart, which are not available with
forms. We plan to use third party java component (e.g ILOG
jviews), so that in future we can easily web enable the entire
application.
Q2. Can we run forms with java bean in client server mode? If
not, what are the products to be installed on each machine to
run it without using 9ias?
best regards

Yes. We can run sql loader from client machine.
C:\Karthik>sqlldr user/pass@database data='test.csv' control='test.ctl' log='test.log' bad='test.bad'
You can go through the following link for better understanding.
http://www.oreilly.com/catalog/orsqlloader/chapter/ch01.html

Lookup of CMP Bean from client

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