Macromedia flash remoting mx-using flash remoting for flash mx 2004 actionscript 2.0 Manuel D’Utilisation

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Chapter 7:  Using Flash Remoting for Java

Calling Enterprise JavaBeans (EJBs) from Flash

The following sections describe how to get a reference to an EJBHome object and call Enterprise 
JavaBeans (EJB) methods from ActionScript.

Getting a reference to an EJBHome object in ActionScript

Before calling the methods of an EJB from ActionScript, you must get a reference to an 
EJBHome object.

To get a reference to an EJBHome object:

1.

Import the mx.remoting.Service file:

import mx.remoting.Service;

2.

Connect to the Flash Remoting gateway and get a reference to the EJBHome object:

SampleLoanHome = new Service(

"http://localhost/flashservices/gateway",
null,
"SampleLoan",
null,
null);

The first parameter of the Service object is the gateway URL. The third parameter is the Java 
Naming and Directory Interface (JNDI) name of the EJBHome object. The JNDI name 
cannot contain a period (.).

Note: There are several other ways to specify the gateway URL. For more information, see 

Invoking EJB methods in ActionScript

Unlike JavaBeans and Java classes, you must invoke the 

create()

 method of an EJBHome object 

and return an EJBObject object before calling EJBObject methods. After you call the 

create()

 

method of an EJBHome object, you can use the ActionScript 

create_Result(re:ResultEvent)

 function to get a reference to the EJBObject object and 

invoke its methods. 

For example, the following method of a stateless session bean performs loan calculations based on 
loan principal, term, and interest rate:

public double calculate(double principal, int months, float rate){
      if (rate < 0 || rate>1) return 0.0;
      double monthlyPayment = principal * (rate / (1 - Math.pow(1 + 

rate,-months)));

      return monthlyPayment;
    }

To invoke the preceding method, you could use the following ActionScript code:

import mx.remoting.Service;
import mx.remoting.PendingCall;
import mx.rpc.RelayResponder;
import mx.rpc.FaultEvent;
import mx.rpc.ResultEvent;