Use this topic to create a mediation that chooses a particular forward route for a
message.
For an introduction to using mediations with the service integration bus, see Learning about mediations. For details of how to install a mediation
into WebSphere Application Server and associate it with a bus destination, see Working with mediations.
This topic assumes that you are familiar with using a Java Platform, Enterprise Edition
(Java EE)
session bean development environment such as the assembly tools or IBM® Rational® Application Developer.
About this task
A routing mediation is a mediation application that contains a routing handler. You associate a
routing mediation with a service integration bus destination, and use the mediation to choose a
particular route from a range of available routes. For example when you create a new outbound service configuration
or modify an existing outbound service
configuration you can apply a port selection mediation to choose a particular outbound port
from the range of ports that are available to the outbound service.
To create a routing mediation, use a Java Platform, Enterprise Edition (Java EE) session bean development
environment to complete the following steps:
- Create an empty mediation handler project.
This creates the project, and
creates the handler class that implements the handler interface. For detailed instructions on how to
do this, see
Writing the mediation
handler.
- Use the mediation pane on the EJB descriptor to define the handler class as a mediation
handler.
Note: When you do this, you specify a name by which the mediation handler list is known. Make a note
of this name, for later reference when you create the mediation in the bus.
- Add the routing function to the handler.
Before you begin, review
Adding mediation function to handler code, in particular its
subtopic
Working with message context. Add import
statements to your handler class, and modify the handle method by adding your routing code. Specify
the routing destination by adding that destination to the front of the forward routing path list.
The forward routing path list is available from the message context. For
example:
import javax.xml.rpc.handler.MessageContext;
import com.ibm.websphere.sib.mediation.handler.MediationHandler;
import com.ibm.websphere.sib.mediation.handler.MessageContextException;
import com.ibm.websphere.sib.mediation.messagecontext.SIMessageContext;
import com.ibm.websphere.sib.SIMessage;
import com.ibm.websphere.sib.SIDestinationAddress;
import com.ibm.websphere.sib.SIDestinationAddressFactory;
import java.util.List;
public class RouteMediationHandler implements MediationHandler {
public boolean handle(MessageContext ctx) throws MessageContextException {
SIMessageContext siCtx = (SIMessageContext) ctx;
SIMessage msg = siCtx.getSIMessage();
List frp = msg.getForwardRoutingPath();
try {
SIDestinationAddress destination =
SIDestinationAddressFactory
.getInstance()
.createSIDestinationAddress(
"RoutingDestination", //this is the name of the target destination
false);
frp.add(0, destination);
} catch (Exception e) {
return false;
}
msg.setForwardRoutingPath(frp);
return true;
}
}
For
more information about the service integration technologies classes, including the mediation handler
and message context classes, see the
Generated
API documentation - Application programming interfaces.
- Export the routing mediation enterprise application.
What to do next
You are now ready to install your mediation into WebSphere Application Server
and associate it with a bus destination, as described in Working with mediations.