import calculator.*;
import org.omg.CORBA.*;
import org.omg.CosNaming.*;
import org.omg.PortableServer.*;
import org.omg.CosNaming.NamingContextPackage.*;

// This class implements a very simple CORBA server.
// It provides add, sub, and mult methods that 
// clients may invoke.
//
// This Server requires that a CORBA Name Service be running.
//
// Written by: Stuart Hansen
// Date: February 2, 2009
public class CalculatorServer extends CalculatorPOA{

    private ORB orb;  // the orb for this server
    private POA rootpoa; // the root POA for this server

    // The constructor sets up the ORB for communication
    public CalculatorServer (String [] args)
    {
        setUpServerORB(args);
    }

    // implement the add method
    public int add(int a, int b) 
    {    
        return a + b;
    }
  
    // implement the sub method
    public int sub(int a, int b) 
    {    
        return a - b;
    }

     // implement the mult method
    public int mult(int a, int b) 
    {    
        return a * b;
    }
      
    // This method setups the Server ORB
    public void setUpServerORB(String [] args)
    {
        try{
            // create and initialize the ORB
            orb = ORB.init(args, null);

            // get reference to rootpoa & activate the POAManager
            rootpoa = POAHelper.narrow(
                orb.resolve_initial_references("RootPOA"));
            rootpoa.the_POAManager().activate();

            // Convert our server to a CORBA object and IOR
            org.omg.CORBA.Object ref = 
                rootpoa.servant_to_reference(this);
            Calculator calc = CalculatorHelper.narrow(ref);
	  
            // Look up the Name Service
            org.omg.CORBA.Object nameServiceObj = 
              orb.resolve_initial_references("NameService");
            NamingContextExt nameService = 
                NamingContextExtHelper.narrow(nameServiceObj);

            // Bind (register) the Calculator Server with the Name Service
            String name = "CalculatorServer";
            NameComponent path[] = nameService.to_name( name );
            nameService.rebind(path, calc);

            System.out.println("Calculator Server Ready");

            // wait for client requests
            orb.run();

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

    // The main program simply creates a new Calculator Server
    public static void main(String [] args) {
      new CalculatorServer(args);
    }
}