Occasions might arise when you want to access a service with Java™ interfaces
from a component that can only support WSDL references. However, you cannot
directly draw a wire from a WSDL-typed reference to a Java component
or a stateless session bean EJB import that has a Java interface. As well, most component
implementations do not allow Java-typed references. The assembly editor provides
an easy way of overcoming this difficulty.
Most components in the assembly diagram use WSDL interfaces and references.
If such a component needs to call a Java component or a stateless session bean
EJB import that has a Java interface, you will not be able
to wire the source component's WSDL reference directly to the session bean
import that has the Java interface. However, WebSphere® Integration
Developer allows you to drag a Java class or a stateless session bean onto
the assembly editor canvas as a component or import, respectively. The editor
then provides the option to generate a facade map component with a Java reference
and a WSDL interface to make it easy for you to complete the wiring. Here
are the step-by-step instructions:
- Locate the existing Java implementation or stateless session
bean that you want to use. You can find the Java implementation
in the Java Package Explorer view or the .java file in the
Physical Resources view. To find the stateless session bean EJB, open the
J2EE perspective and locate the bean in its Project Explorer view.
- Drag your Java object into your assembly diagram. A Java class becomes a component when it is dropped on
the canvas. A stateless session bean becomes an import.
- You are prompted to create a facade map component. Click Yes. A facade map component with a WSDL interface and an equivalent Java reference
is created. This facade map component automatically converts the incoming
event for the WSDL interface to the equivalent Java outgoing event sent to the service
wired to its reference. The following detail from the assembly diagram shows
a facade map component, Bridge, that is wired to a stateless session bean
import, SLSBImport:

- Draw a wire from the business process component to the WSDL interface
of the bridge component in the assembly. The editor creates a matching
WSDL reference on the BusinessProcess component to complete the bridge. The
facade map component does not contain any business logic; it just enables
a connection between the Java interface and the WSDL reference. The
following assembly diagram shows that the BusinessProcess component is wired
through the Bridge component to the SLSBImport Java import:

Your process component can now successfully call the Java component
or EJB import.