EJB export bindings

External Java™ EE applications can invoke an SCA component by way of an EJB export binding. Using an EJB export lets you expose SCA components so that external Java EE applications can invoke those components using the EJB programming model.

Note: The EJB export is a stateless bean.

You use Integration Designer to create EJB bindings. You can use either of the following procedures to generate the bindings:

Creating EJB export bindings using the external service wizard
You can use the external service wizard in Integration Designer to build an EJB export service based on an existing implementation. The external service wizard creates services based on criteria that you provide. It then generates business objects, interfaces, and export files based on the services discovered.
Creating EJB export bindings using the assembly editor
You can create an EJB export using the Integration Designer assembly editor.

Important: A Java 2 Platform, Standard Edition (J2SE) client cannot invoke the EJB export client that is generated in Integration Designer.

You can generate the binding from an existing SCA component, or you can generate an export with an EJB binding for a Java interface.

When you generate an export for an existing SCA component that has an existing WSDL interface, the export is assigned a Java interface.
When you generate an export for a Java interface, you can select either a WSDL or a Java interface for the export.
Note: A Java interface used to create an EJB export has the following limitations with regard to the objects (input and output parameters and exceptions) passed as parameters on a remote call:
- They must be of concrete type (instead of an interface or abstract type).
- They must conform to the Enterprise JavaBeans specification. They must be serializable and have the default no-argument constructor, and all properties must be accessible through getter and setter methods.
  Refer to the Sun Microsystems, Inc., Web site at http://java.sun.com for information about the Enterprise JavaBeans specification.
In addition, the exception must be a checked exception, inherited from java.lang.Exception, and it must be singular (that is, it does not support throwing multiple checked exception types).

Note also that the business interface of a Java EnterpriseBean is a plain Java interface and must not extend javax.ejb.EJBObject or javax.ejb.EJBLocalObject. The methods of the business interface should not throw java.rmi.Remote.Exception.

The EJB export bindings can interact with Java EE business logic using either the EJB 2.1 programming model or the EJB 3.0 programming model.

The invocation can be local (for EJB 3.0 only) or remote.

Local invocation is used when the Java EE business logic calls an SCA component that resides on the same server as the export.
Remote invocation is used when the Java EE business logic does not reside on the same server as the export.
For example, in the following figure, an EJB uses RMI/IIOP to call an SCA component on a different server.
Figure 1. Remote call from a client to an SCA component by way of an EJB export

When it configures the EJB binding, Integration Designer uses the JNDI name to determine the EJB programming model level and the type of invocation (local or remote).

EJB export bindings contain the following major components:

JAX-WS data handler
EJB export function selector

If your user scenario is not based on the JAX-WS mapping, you might need a custom data handler and function selector to perform the tasks otherwise completed by the components that are part of the EJB export bindings. This includes the mapping normally completed by the custom mapping algorithm.