Step #2 : Specify The Enterprise
Java Bean Remote Interface
The remote interface is the clients view of the EJB the task of the
EJB developer is to declare this interface in normal Java RMI
syntax it it the responsibility of the Enterprise Java Bean container tools
provider to generate the implementation of this interface.
There are limitations on what can be specified in this interface, please
refer to the EJB specification (sectoin #16 ) but importantly all of the
objects used and parameters, return values and exceptions must be valid
types in the "java to IDL mapping specification"
for our simple DemoBean the remote interface looks like
/**
* Demo -- this is the "remote" interface
of our Enterprise Java Bean, it
*
defines only one simple method called demoSelect() which as this is
*
a stateless minimal bean example it just returns a string, no
*
database lookup is attempted.
*
* Note: The implementation of this
interface is provided by the container tools
*
but the demoSelect() method and any other methods in this interface
*
will need to have equivalent implementations in the DemoBean.java
*
implementation which is supplied by the bean Writer ..i.e. you!
*/
package ejb.demo;
import java.rmi.RemoteException;
import java.rmi.Remote;
import javax.ejb.*;
public interface Demo extends EJBObject, Remote {
// NB this simple example does not even
do a lookup in the database
public String
demoSelect() throws RemoteException;
}
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