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The 2nd part of the 2 part article discusses the EJB Deployment, Troubleshooting and Environment Variables affecting the setup of the EJB Server

Publishing EJB's in the Database (Deployment)

Similar to PL/SQL stored procedures and java stored procedures, EJB's are "deployed" into the database. The EJB and CORBA objects have their own namespace within the Oracle database, this is called a session namespace. The namespace is managed by the sess_sh command under NT.

The session namespace is like a Unix directory structure. It consists of a hierarchical collection of 'Published Contexts' (directories) and 'Published Nodes' (files). Each node represents a stored EJB or CORBA object, these are called by client applications and are instantiated in the Java Shared Pool via the Oracle 8i ORB.

In order to publish EJB's, you need to setup the session namespace, this can be done with the publish command line tool OR the interactive sess_sh (session shell). The initial publishing contexts are:

D:>sess_sh -user scott -password tiger
-service sess_iiop://myhostname:2481:mysdbid

--Aurora/ORB Session Shell--
--type "help" at the command line for help message

$ ls -l
Read Write Exec Owner Date Time Name Schema Class Helper
PUBLIC SYS PUBLIC SYS Sep 07 08:59 bin/
PUBLIC SYS PUBLIC SYS Sep 07 08:59 etc/
PUBLIC PUBLIC PUBLIC SYS Sep 07 08:59 test/
$

From within sess_sh you can republish EJB's, manage access rights and much more.

To initially 'publish' a EJB into the database, developers use the deployejb command line application. This will load and publish the EJB for the developer. The developer must have write access to publish objects. By default all published objects will reside in the /test context.

The deployejb command will use the 'deployment descriptor' file supplied by the developer to control how the EJB is deployed to the database. The suggested extension of the deployment descriptor text file is *.ejb.

The interactive shell is highly recommended over the command line tools when learning how to manipulate the session namespace.

deployejb -republish -temp temp -u myejbuser -p mypassword -s sess_iiop://myhostname:2481:mydbsid -descriptor hello.ejb server.jar

Reading Deployment Descriptor...done
Verifying Deployment Descriptor...done
Gathering users...done
Generating Comm Stubs.....................................done
Compiling Stubs...done
Generating Jar File...done
Loading EJB Jar file and Comm Stubs Jar file...done
Generating EJBHome and EJBObject on the server...done
Publishing EJBHome...done

A deployed EJB can be removed from the database via the remove command line program or via sess_sh.

Troubleshooting

• It is critical that the CLASSPATH settings are correct otherwise deployment and compilation will not work.
• Work closely with the developers with deployment to the database. It is to easy to deploy everything to /test, learn how the namespace works, security access for the client to the deployed beans and understand the publishing process.
• Re-learn multi-threaded server (MTS), and how to tune it.
  There is little tuning information that you can gleam from the Java Shared Pool. Whilst in NT, check Oracle Handle counts, memory usage and try various MTS settings.
• Pick the correct JDK, Oracle v8.1.5 only supports JDK 1.1.6, not version 2.

Environment Variable Hints

For those still have problems with Environment settings, try these examples.

Compliation

CLASSPATH=.;d:\oracle\Ora81\lib\aurora_client.jar; d:\oracle\Ora81\jdbc\lib\classes111.zip;d:\oracle\Ora81\sqlj\lib\translator.zip; d:\oracle\Ora81\lib\vbjorb.jar; d:\oracle\Ora81\lib\vbjapp.jar;d:\jdk1.1.6; d:\jdk1.1.6\lib;d:\jdk1.1.6\lib\classes.zip

Deployment

Don’t forget to include your server_generated.jar file.

Command line Test

java -classpath %CLASSPATH% Client sess_iiop://myhostname:2481:mydbsid /test/myHello olcr olcr

Note

Refer to Oracle 8.1.5 documentation for a comprehensive coverage of Jserver and EJB implementation. Also, it is worth the effort to understand and come to grips with Java terminology and its architecture before working with the EJB developer.

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