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The chapter discusses the following topics:

• How the EJB-to-CORBA/Java Simpapp sample application works

• Software prerequisites

• Building and running the EJB-to-CORBA/Java Simpapp sample application

• Stopping the EJB-to-CORBA/Java Simpapp sample application

  Note: Each sample application directory tree provided with the WLE software includes a Readme.txt file that explains how to build and run the sample. Refer to this file in the following directory for troubleshooting information or other last-minute information about using the EJB-to-CORBA/Java sample application:

  Window NT:

  $TUXDIR\samples\interop\ejb_corbaj

  UNIX:

  $TUXDIR/samples/interop/ejb_corbaj

How the EJB-to-CORBA/Java Simpapp Sample Application Works

The EJB-to-CORBA/Java Simpapp sample application has an EJB client, an EJB server deploying the SimpBean EJB and an EJB-to-CORBA bridge object, and a CORBA server deploying a CORBA object.

The SimpBean EJB has the following two remote methods:

• The upper method delegates invocations to the to_upper method on the CORBA Simple object

• The lower method method delegates invocations to the to_lower method on the CORBA Simple object

The CORBA Simple object has the following two methods:

• The to_upper method accepts a string from the bridge object and converts the string to uppercase letters.

• The to_lower method accepts a string from the bridge object and converts the string to lowercase letters.

The following figure illustrates how the EJB-to-CORBA/Java Simpapp sample application works.

Software Prerequisites

To run the m3idltojava compiler that is used by the EJB-to-CORBA/Java Simpapp sample application, you need to install Visual C++ Version 6.0 with Service Pack 3 or later for Visual Studio. The m3idltojava compiler is installed by the WLE software in the bin directory under TUXDIR .

Implementing the Bridge Object to Invoke a CORBA/Java Object

The SimpleBridge Java object implements bridge design pattern. This object serves as a bridge between the SimpBean EJB and the CORBA/Java Simple object, and it is created by the SimpBean EJB.

The SimpleBridge Java object performs the following functions:

• Uses the Bootstrap object to obtain a reference to the WLE FactoryFinder, from which the SimpleBridge object can obtain a reference to the SimpleFactory object

• Invokes the SimpleFactory object to obtain a reference to the Simple object

• Invokes the appropriate methods on the Simple object to satisfy the SimpBean 's requests.

The following code fragment shows the methods on the SimpleBridge object that delegate the SimpBean 's requests to the CORBA/Java Simple object:

public class SimpleBridge
{
  private Simple simple = null;

  public SimpleBridge ()
  {
    simple = getSimple();
  }

  public String doUpper(String mixedStr)
  {
    // Convert the string to upper case.
    org.omg.CORBA.StringHolder upperStr =
      new org.omg.CORBA.StringHolder(mixedStr);
    simple.to_upper(upperStr);

    System.out.println("in SimpleBridge.doUpper()");
    return upperStr.value;
  }


  public String doLower(String mixedStr)
  {
    // Convert the string to lower case.
    String lowerStr = simple.to_lower(mixedStr);

    System.out.println("in SimpleBridge.doLower()");
    return lowerStr;
  }


  public Simple getSimple()
  {
    try {
      // Obtain the bootstrap object,
      // the TOBJADDR property contains host and port to connect to.
      Tobj_Bootstrap bootstrap = TP.bootstrap();

      // Use the bootstrap object to find the factory finder.
      org.omg.CORBA.Object fact_finder_oref =
        bootstrap.resolve_initial_references("FactoryFinder");

      // Narrow the factory finder.
      FactoryFinder fact_finder_ref =
        FactoryFinderHelper.narrow(fact_finder_oref);

      // Use the factory finder to find the simple factory.
      org.omg.CORBA.Object simple_fact_oref =
        fact_finder_ref.find_one_factory_by_id(SimpleFactoryHelper.id());

      // Narrow the simple factory.
      SimpleFactory simple_factory_ref =
        SimpleFactoryHelper.narrow(simple_fact_oref);

      // Find the simple object.
      Simple simple = simple_factory_ref.find_simple();

      // everything succeeded.
      return simple;
    }
    // catch the exceptions
    return null;
  }
}

The sample application described in this chapter implements the CORBA interfaces listed in the following table.

Interface	Description	Operation	Policies
SimpleFactory	Creates object references to the Simple object	find_simple()	Activation: method Transaction: optional
Simple	Converts the case of a string	to_upper() to_lower()	Activation: method Transaction: optional

Listing 2-1 shows the simple.idl file that defines the CORBA interfaces in the EJB-to-CORBA/Java Simpapp sample application.

Listing 2-1 OMG IDL Code for the EJB-to-CORBA/Java Simpapp Sample Application

#pragma prefix "beasys.com"

interface Simple
{
    //Convert a string to lower case (return a new string)
    string to_lower(in     string val);

    //Convert a string to upper case (in place)
    void to_upper(inout string val);
};

interface SimpleFactory
{
    Simple find_simple();
};

Perform the following steps to build and run the EJB-to-CORBA/Java Simpapp sample application:

1. Verify the environment variables.

2. Copy the files for the EJB-to-CORBA/Java Simpapp sample application into a work directory.

3. Change the protection attribute on the files for the EJB-to-CORBA/Java Simpapp sample application.

4. Execute the runme command.

The following sections describe these steps, and also explain the following:

• How to run the EJB-to-CORBA/Java Simpapp sample application

• Processes and files created by the EJB-to-CORBA/Java Simpapp sample application

Verifying the Settings of the Environment Variables

Before building and running the EJB-to-CORBA/Java Simpapp sample application, you need to ensure that certain environment variables are set on your system. In most cases, these environment variables are set as part of the installation procedure. However, you need to check the environment variables to ensure they reflect correct information.

Table 2-1 lists the environment variables required to run the EJB-to-CORBA/Java Simpapp sample application.

Table 2-1 Required Environment Variables for the EJB-to-CORBA/Java Simpapp Sample Application

Environment Variable	Description
TUXDIR	The directory path where you installed the WLE software. For example: Windows NT TUXDIR=c:\WLEdir UNIX TUXDIR=/usr/local/WLEdir
JAVA_HOME	The directory path where you installed the JDK software. For example: Windows NT JAVA_HOME=c:\JDK1.2.2 UNIX JAVA_HOME=/usr/local/JDK1.2.1

You may optionally set the following system environment variables to change their default value prior to running the EJB-to-CORBA/Java Simpapp sample application runme command. See the Administration Guide for more information about selecting appropriate values for these environment variables.

Table 2-2 lists the optional environment variables required to run the EJB-to-CORBA/Java Simpapp sample application.

Table 2-2 Optional Environment Variables for the EJB-to-CORBA/Java Simpapp Sample Application

Environment Variable	Description
HOST	The host name portion of the TCP/IP network address used by the ISL process to accept connections from CORBA. The default value is the name of the local machine.
PORT	The TCP port number at which the ISL process listens for incoming requests; it must be a number between 0 and 65535. The default value is 2468.
IPCKEY	The address of shared memory; the address must be a number greater than 32769 unique to this application on this system. The default value is 55432.

Verifying the Environment Variables

To verify that the information for the environment variables defined during installation is correct, perform the following steps:

Windows NT:

1. From the Start menu, select Settings.

2. From the Settings menu, select the Control Panel.

   The Control Panel appears.

3. Click the System icon.

   The System Properties window appears.

4. Click the Environment tab.

   The Environment page appears.

5. Check the settings for TUXDIR and JAVA_HOME .

UNIX:

1. Enter the ksh command to use the Korn shell.

2. Enter the printenv command to display the values of TUXDIR and JAVA_HOME , as in the following example:

   ksh prompt>printenv TUXDIR
   ksh prompt>printenv JAVA_HOME

To change the environment variable settings, perform the following steps:

Windows NT:

1. From the Start menu, select Settings.

2. From the Settings menu, select the Control Panel.

   The Control Panel appears.

3. Click the System icon.

   The System Properties window appears.

4. Click the Environment tab.

   The Environment page appears.

5. On the Environment page in the System Properties window, click the environment variable you want to change or enter the name of the environment variable in the Variable field.

6. Enter the correct information for the environment variable in the Value field.

7. Click OK to save the changes.

UNIX:

1. Enter the ksh command to use the Korn shell.

2. Enter the export command to set the correct values for the TUXDIR and JAVA_HOME environment variables, as in the following example:

   ksh prompt>export TUXDIR= directorypath
   ksh prompt>export JAVA_HOME= directorypath

You need to copy the files for the EJB-to-CORBA/Java Simpapp sample application into a work directory on your local machine. The files for the EJB-to-CORBA/Java Simpapp sample application are located in the following directories under TUXDIR:

Windows NT:

$TUXDIR\samples\interop\ejb_corbaj

UNIX:

$TUXDIR/samples/interop/ejb_corbaj

The following steps describe how to execute a makefile to copy all the example files into a work directory.

1. Create the work directory on your machine.

2. Copy the entire ejb_corbaj directory to the working directory created in the previous step:

Windows NT:

> copy $TUXDIR\samples\interop\ejb_corbaj\*.* <work_directory>

UNIX:

> cp -R $TUXDIR/samples/interop/ejb_corbaj/* <work_directory>

1. Change to the working directory created in step 1.

2. Enter the following command, which copies the remaining EJB-to-CORBA/Java Simpapp sample application files to the working directory:

   Windows NT:

   >nmake -f makefile.nt copy

   UNIX:

   >make -f makefile.mk copy

This section lists and describes the files copied into your working directory after you have performed the steps described in the previous section.

The EJB-to-CORBA/Java Simpapp sample application files exist in the following sets:

• EJB Simpapp files

• CORBA/Java Simpapp files

• EJB-to-CORBA/Java utility files

Table 2-3 lists and describes the source files for the EJB portion of this sample application. These are the files that exist after you do the make command. These files are copied into a subdirectory named ejb .

Table 2-3 EJB Simpapp Files

File	Description
ejb-jar.XML	The standard deployment descriptor for the SimpBean class.
weblogic-ejb-extensions.XML	The XML file specifying the WebLogic EJB extensions to the deployment descriptor DTD.
SimpClient.Java	The EJB Simpapp client.
SimpBean.java	The SimpBean class. This is an example of a stateless session bean. This bean contains the methods that invoke the SimpleBridge class to delegate the invocations on the Simple CORBA/Java object.
Simp.java	The Remote interface of the SimpBean class.
SimpHome.Java	The Home interface of the SimpBean class.

Table 2-4 lists and describes the source files for the CORBA/Java portion of this sample application. They are copied into a subdirectory named corbaj .

Table 2-4 CORBA/Java Simpapp Files

File	Description
Simple.idl	The OMG IDL that declares the SimpleFactory and Simple interfaces.
Simple.xml	The Server Description File for the Simple CORBA object.
SimpleBridge.Java	The EJB-to-CORBA/Java Simpapp SimpleBridge class. This class is used by the SimpBean class to communicate with the CORBA/Java Simple object. This is the class that effects the interoperability between the EJB and the CORBA/Java object.
ServerImpl.Java	The implementation of the Server.initialize and Server.release methods.
SimpleFactoryImpl.Java	The implementation of the SimpleFactory methods.
SimpleImpl.Java	The implementation of the Simple methods.

Table 2-5 lists and describes the utility files for this sample application.

Table 2-5 EJB-to-CORBA/Java Utility Files

File	Description
Readme.txt	Contains directions for building and executing the EJB-to-CORBA/Java Simpapp sample application.
runme.cmd	The Windows NT batch file that contains commands to build and execute the EJB-to-CORBA/Java Simpapp sample application.
runme.ksh	The UNIX Korn shell script that contains commands to build and execute the EJB-to-CORBA/Java Simpapp sample application.
makefile.nt	The common makefile for the EJB-to-CORBA/Java Simpapp sample application on the Windows NT platform. This makefile can be used directly by the Visual C++ nmake command. The makefile.nt file is included by the smakefile.nt file.
smakefile.nt	The makefile for the EJB-to-CORBA/Java Simpapp sample application to be used by Symantec's Visual Café smake program.
makefile.mk	The makefile for the EJB-to-CORBA/Java Simpapp sample application on the UNIX platform.

Changing the Protection Attribute on the Files for the EJB-to-CORBA/Java Simpapp Sample Application

During the installation of the WLE software, the sample application files are marked read-only. Before you can edit or build the files in the EJB-to-CORBA/Java Simpapp sample application, you need to change the protection attribute of the files you copied into your work directory (including the respective ejb and corbaj subdirectories), as follows:

Windows NT:

prompt>attrib /S -r drive: \workdirectory \*.*

UNIX:

prompt>/bin/ksh

ksh prompt>chmod +w / workdirectory /*.*

On the UNIX operating system platform, you also need to change the permission of runme.ksh to give execute permission to the file, as follows:

ksh prompt>chmod +x runme.ksh

Executing the runme Command

The runme command automates the following steps:

1. Setting the system environment variables

2. Loading the UBBCONFIG file

3. Compiling the code for the EJB server object

4. Compiling the code for the CORBA/Java server application

5. Starting the server application using the tmboot command

6. Starting the client application

7. Stopping the server application using the tmshutdown command

To build and run the EJB-to-CORBA Simpapp sample application, enter the runme command, as follows:

Windows NT:

prompt>cd workdirectory

prompt>runme

UNIX:

ksh prompt>cd workdirectory

ksh prompt>./runme.ksh

The EJB-to-CORBA/Java Simpapp sample application runs and prints the following messages:

Testing simpapp
    cleaned up
    prepared
    built
    loaded ubb
    booted
    ran
    shutdown
    saved results
  PASSED

All of the sample application output is placed in the results directory, which is located in the ejb_corbaj working directory. You can check in the results directory for the following files:

• The log file, for any compile, server boot, or server shutdown errors

• The ULOG file for server application errors and exceptions

• The output file for EJB client application output and exceptions

Running the Sample Application

After you have executed the runme command, you can run the EJB-to-CORBA/Java Simpapp sample application manually if you like.

To manually run the EJB-to-CORBA/Java Simpapp sample application:

1. Verify that your environment variables are correct by entering the following command:

   Windows NT:

   prompt>results\setenv

   UNIX:

   prompt>. results/setenv.ksh

2. Run the sample, as follows:

   Windows NT:

   prompt>tmboot -y
   prompt>java -classpath %CLIENTCLASSPATH% ejb.SimpClient corbaloc:%TOBJADDR%

   UNIX:

   prompt>tmboot -y
   prompt>java -classpath ${CLIENTCLASSPATH} ejb.SimpClient corbaloc:${TOBJADDR}

3. The EJB-to-CORBA/Java Simpapp sample application prompts you to enter a string. After you enter the string, the application returns the string in uppercase and lowercase characters, respectively:

   String?
   Hello World
   HELLO WORLD
   hello world

All of the sample application output is placed in the results directory. You can check in that directory for the following files:

• The .log file, for any compile, server boot, or server shutdown errors

• The ULOG file for server application errors and exceptions

• The output file for EJB client application output and exceptions

Processes and Files Generated by the EJB-to-CORBA/Java Simpapp Sample Application

This section lists and describes the processes started and the files generated by the EJB-to-CORBA/Java Simpapp sample application.

Processes Started

When the tmboot command is executed to start the EJB-to-CORBA/Java Simpapp sample application, the following server processes are started:

Process	Description
TMSYSEVT	The BEA Tuxedo system Event Broker.
TMFFNAME	Starts the following TMFFNAME processes: The TMFFNAME server process with the -N option and the -M option is the MASTER NameManager service. The -N option says to start the NameManager Service; the -M option says to start this name manager as a Master. This service maintains a mapping of application-supplied names to object references. The TMFFNAME server process with the -N option only is a SLAVE NameManager service. The TMFFNAME server with the -F option contains the FactoryFinder object.
JavaServer	The JavaServer process that deploys the SimpBean EJB and hosts the implementation of the SimpBridge CORBA object. The JavaServer takes one argument, SimpleEjb.jar , which is the module for the SimpBean EJB.
JavaServer	The JavaServer process which deploys the Simple CORBA object (the deployment of this process also includes the SimpleFactory factory for the Simple object). The JavaServer takes one argument, SimpleCorba.jar , which is the module for the Simple CORBA object.
ISL	The IIOP Listener/Handler.

Files Generated in the corbaj Directory

The following table lists and describes the files that are generated in the corbaj working directory.

File	Description
Simple.java	Generated by the m3idltojava command for the Simple interface. This interface contains the Java version of the IDL interface. It extends the org.omg.CORBA.Object class.
SimpleHelper.java	Generated by the m3idltojava command for the Simple interface. This class provides auxiliary functionality, notably the narrow method.
SimpleHolder.java	Generated by the m3idltojava command for the Simple interface. This class holds a public instance member of type Simple . It provides operations for out and inout arguments, which CORBA has, but which do not map easily to Java's semantics.
_SimpleImplBase.java	Generated by the m3idltojava command for the Simple interface. This abstract class is the server skeleton. It implements the Simple.java interface. The server class SimpleImpl extends _SimpleImplBase .
_SimpleStub.java	Generated by the m3idltojava command for the Simple interface. This class is the client stub. It implements the Simple.java interface.
SimpleFactory.java SimpleFactoryHelper.java SimpleFactoryHolder.java _SimpleFactoryImplBase.java _SimpleFactoryStub.java	Generated by the m3idltojava command for the SimpleFactory interface.
Simple.ser	The server descriptor file that is generated by the buildjavaserver command.
Simple.jar	The Java archive file that is generated by the buildjavaserver command.

File Generated in the ejb_corbaj Directory

The following file is generated in the ejb_corbaj directory:

results directory	Generated by the runme comand.
.adm/.keydb	Generated by the tmloadcf command. Contains the security encryption key database.

Files Generated in the results Directory

The following table lists and describes the files that are generated in the results directory, which is a subdirectory of the ejb_corbaj working directory.

File	Description
input	Generated by the runme command. Contains the input that runme gives to the SimpleClient Java application.
output	Generated by the runme command. Contains the output that is produced when runme executes the SimpleClient Java application.
expected_output	Generated by the runme command. Contains the output that is expected when the SimpleClient Java application is executed by the runme command. The data in the output file is compared with the data in the expected_output file to determine whether the test passed or failed.
log	Generated by the runme command. Contains the output generated by the runme command. If the runme command fails, check this file and the ULOG file for errors.
setenv.cmd	Generated by the Windows NT runme.cmd command. Contains the commands to set the environment variables needed to build and execute the EJB-to-CORBA/Java Simpapp sample application.
setenv.ksh	Generated by the UNIX runme.ksh command. Contains the commands to set the environment variables needed to build and execute the Simpapp sample.
stderr	Generated by the tmboot command, which is executed by the runme command. If the -noredirect server option is specified in the UBBCONFIG file, the System.err.println method sends the output to the stderr file instead of to the ULOG user log file.
stdout	Generated by the tmboot command, which is executed by the runme command. If the -noredirec t server option is specified in the UBBCONFIG file, the System.out.println method sends the output to the stdout file instead of to the ULOG user log file
tmsysevt.dat	Generated by the tmboot command, which is executed by the runme command. It contains filtering and notification rules used by the TMSYSEVT (system event reporting) process.
tuxconfig	Generated by the tmloadcf command, which is executed by the runme command.
ubb	The UBBCONFIG file for the EJB-to-CORBA/Java Simpapp sample application.
ULOG.< date >	A log file that contains messages generated by the tmboot command. If there are any compile or run-time errors, check this file.

Stopping the EJB-to-CORBA/Java Simpapp Sample Application

Before using another sample application, use the following procedure to stop the EJB-to-CORBA/Java Simpapp sample application and to remove unnecessary files from the work directory.

1. Stop the application:

   Windows NT:

   prompt>tmshutdown -y

   UNIX:

   ksh prompt>tmshutdown -y

2. Restore the working directory to its original state:

   Windows NT:

   prompt>nmake -f makefile.nt clean

   UNIX:

   prompt>. ./results/setenv.ksh
   prompt>make -f makefile.nt clean

3. If Symantec's Visual Café is installed on your system, you can use the smakefile.nt file rather than the makefile.nt file, which is intended for use with the Visual C++ nmake program. For example, execute the following commands:

   prompt>results\setenv
   prompt>set JDKDIR=%JAVA_HOME%
   prompt>smake -f smakefile.nt