Creating stub instances

A Java stub implements the Java version for one of the EAServer component’s IDL interfaces. Call the Session.lookup method to obtain a factory for stub instances. The signature of Session.lookup is:

SessionManager.Factory lookup(String name)

The code to call Session.lookup and Factory.create looks like this:

import org.omg.CORBA.*;
import SessionManager.*;
import java.awt.*;
import Calculator.*;  // Package for Java stubs
                      // for this example, matches
                      // IDL module name for the 
                      // component’s interface.

public class myApplet extends Applet {

  Session session;

  ... deleted code that created Session instance
      ...

  //
  // In this example, the component is named calc
  // and is installed in the EAServer package
  // calculator. calcHelper.narrow() verifies that
  // the returned object is of the appropriate
  // type, then returns a Calculator.Calc instance
  //
  try {
    Factory fact = 
      FactoryHelper.narrow(
        session.lookup("calculator/calc"));
    Calc c = 

      CalcHelper.narrow(fact.create());
  } 
  catch (org.omg.CORBA.OBJECT_NOT_EXIST one)
  {

    // Tell the user to contact the server
    // administrator
    ... report the error ...
  }
  catch (org.omg.CORBA.NO_PERMISSION np)
  {
    // Tell the user they are not authorized
    ... report the error ...
  }
  catch (org.omg.CORBA.SystemException se)
  {
    // Catch-all clause for any CORBA system
    // exception that was not explicitly caught
    // above. 
    ... report the error ...
  }