SERVER SIDE

1. Create a new Java Project and call it : CorbaAdditionServer

2. Create an  empty file and save it with an *.idl extension and compile using idlj - fall Addition.idl

module AdditionApp
{
  //do not use an interface name as the name of a module
  interface Addition
  {
    long add(in long a,in long b);
    oneway void shutdown();
    };
};

3. Generates 6 files automatically

POA - the server skeleton
Holder - the instance "holder"
Helper - provides functions for casting references to their types
Stub - the client stub
Operations = the operations specific to the app
Addition.java = the "signature" file implementing the addition contract

4. Create a new class called AdditionObj

import AdditionApp.*;
import org.omg.CosNaming.*;
import org.omg.CosNaming.NamingContextPackage.*;
import org.omg.CORBA.*;
import org.omg.PortableServer.*;
import org.omg.PortableServer.POA;
import java.util.Properties;

class AdditionObj extends AdditionPOA {
  private ORB orb;

  public void setORB(ORB orb_val) {
    orb = orb_val;
  }

  // implement add() method
  public int add(int a, int b) {
    int r=a+b;
    return r;
  }

  // implement shutdown() method
  public void shutdown() {
    orb.shutdown(false);
  }
}

5. Create a Class called StartServer

import AdditionApp.*;
import org.omg.CosNaming.*;
import org.omg.CosNaming.NamingContextPackage.*;
import org.omg.CORBA.*;
import org.omg.PortableServer.*;
import org.omg.PortableServer.POA;
import java.util.Properties;

public class StartServer {

  public static void main(String args[]) {
    try{
      // create and initialize the ORB //// get reference to rootpoa & activate the POAManager
      ORB orb = ORB.init(args, null);
      POA rootpoa = POAHelper.narrow(orb.resolve_initial_references("RootPOA"));
      rootpoa.the_POAManager().activate();

      // create servant and register it with the ORB
      AdditionObj addobj = new AdditionObj();
      addobj.setORB(orb);

      // get object reference from the servant
      org.omg.CORBA.Object ref = rootpoa.servant_to_reference(addobj);
      Addition href = AdditionHelper.narrow(ref);

	  // get the root naming context
      // NameService invokes the name service
      org.omg.CORBA.Object objRef =  orb.resolve_initial_references("NameService");

	  // Use NamingContextExt which is part of the Interoperable
      // Naming Service (INS) specification.
	  NamingContextExt ncRef = NamingContextExtHelper.narrow(objRef);

      // bind the Object Reference in Naming
	  NameComponent path[] = ncRef.to_name( "ABC" );
      ncRef.rebind(path, href);

      System.out.println("Addition Server ready and waiting ...");

      // wait for invocations from clients
      for (;;){
	  orb.run();
      }
    }

      catch (Exception e) {
        System.err.println("ERROR: " + e);
        e.printStackTrace(System.out);
      }

      System.out.println("HelloServer Exiting ...");

  }
}

6. Open a new CMD console and type in the command below

start orbd -ORBInitialPort 1050

i.) Click Run on the IDE -> Run Configuration
ii.) Select the StartServer for the CorbaAdditionServer
iii.)  Click on Arguments and type in : -ORBInitialPort 1050 -ORBInitialHost localhost

//The server should be running.

CLIENT SIDE

1. Create a new Java Project and call it : CorbaAdditionClient

2. Copy the AdditionApp Package under CorbaAdditionServer on the src Package under CorbaAdditionClient

3. Create a new Class called StartClient

import AdditionApp.*;
import org.omg.CosNaming.*;
import org.omg.CosNaming.NamingContextPackage.*;
import org.omg.CORBA.*;
import java.io.*;
import java.util.*;

public class StartClient {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
      try {

	    // create and initialize the ORB
		ORB orb = ORB.init(args, null);

		// get the root naming context
	    org.omg.CORBA.Object objRef =   orb.resolve_initial_references("NameService");

		// Use NamingContextExt instead of NamingContext. This is
        // part of the Interoperable naming Service.
		NamingContextExt ncRef = NamingContextExtHelper.narrow(objRef);

		// resolve the Object Reference in Naming
		Addition addobj = (Addition) AdditionHelper.narrow(ncRef.resolve_str("ABC"));

            Scanner c=new Scanner(System.in);
            System.out.println("Welcome to the addition system:");
		    for(;;){
		      System.out.println("Enter a:");
		      String aa = c.nextLine();
		      System.out.println("Enter b:");
		      String bb = c.nextLine();
		      int a=Integer.parseInt(aa);
		      int b=Integer.parseInt(bb);
		      int r=addobj.add(a,b);
		      System.out.println("The result for addition is : "+r);
		      System.out.println("-----------------------------------");
            }
       }
       catch (Exception e) {
          System.out.println("Hello Client exception: " + e);
	  e.printStackTrace();
       }

    }

}

4. 	i.) Click on Run -> Run Configuration
	ii.) Select the StartClient for the CorbaAdditionClient.
	iii.) Click on Arguments, then under the Program arguments, type in : -ORBInitialPort 1050 -ORBInitialHost localhost
	iv.) Click Apply

5. Run the program =)