How to run the ConverterClient app?

[Zhixiong Pan]

Hi ranchers,

I am fresh in EJB, and trying to run an example in J2EE tutorial.There are 4 classes in total, and the post will be quite large after i list them here.

  import javax.ejb.EJBObject;
import java.rmi.RemoteException;
import java.math.*;
 
public interface Converter extends EJBObject {
   public BigDecimal dollarToYen(BigDecimal dollars) 
      throws RemoteException;
   public BigDecimal yenToEuro(BigDecimal yen) 
      throws RemoteException;
}
 

import java.rmi.RemoteException;
import javax.ejb.CreateException;
import javax.ejb.EJBHome;
 
public interface ConverterHome extends EJBHome {
  Converter create() throws RemoteException, CreateException;
}
 

import java.rmi.RemoteException; 
import javax.ejb.SessionBean;
import javax.ejb.SessionContext;
import java.math.*;
 
public class ConverterBean implements SessionBean {
 
  BigDecimal yenRate = new BigDecimal("121.6000");
  BigDecimal euroRate = new BigDecimal("0.0077");
 
  public BigDecimal dollarToYen(BigDecimal dollars) {
    BigDecimal result = dollars.multiply(yenRate);
    return result.setScale(2,BigDecimal.ROUND_UP);
  }
 
   public BigDecimal yenToEuro(BigDecimal yen) {
      BigDecimal result = yen.multiply(euroRate);
      return result.setScale(2,BigDecimal.ROUND_UP);
   }
 
   public ConverterBean() {}
   public void ejbCreate() {}
   public void ejbRemove() {}
   public void ejbActivate() {}
   public void ejbPassivate() {}
   public void setSessionContext(SessionContext sc) {}
}
 

import javax.naming.Context;
import javax.naming.InitialContext;
import javax.rmi.PortableRemoteObject;
import java.math.BigDecimal;
 
public class ConverterClient {
 
  public static void main(String[] args) {
 
    try {
      Context initial = new InitialContext();
      Context myEnv = 
        (Context)initial.lookup("java:comp/env");
      Object objref = myEnv.lookup("ejb/SimpleConverter");
 
      ConverterHome home = 
        (ConverterHome)PortableRemoteObject.narrow(objref, 
                            ConverterHome.class);
 
      Converter currencyConverter = home.create();
 
      BigDecimal param = new BigDecimal ("100.00");
      BigDecimal amount =
        currencyConverter.dollarToYen(param);
      System.out.println(amount);
      amount = currencyConverter.yenToEuro(param);
      System.out.println(amount);
 
      System.exit(0);
 
    } catch (Exception ex) {
      System.err.println("Caught an unexpected exception!");
      ex.printStackTrace();
    }
  } 
}  

I compiled them all, and try to run ConverterClient and got an exception.Could you help me?

[paresh vernekar]

HI,
Could you post the exact exception that you have got?

Regards,
Paresh Vernekar

[Zhixiong Pan]

Hi,

I have shown you the 4 classes, it is easy to compile and run. Just try it and will only take you 1 minunt.