

You created three service contracts in a single package
for the Invoicing, Scheduling, and Shipping service interfaces. You
added an activity diagram and a sequence diagram to the contracts.
The Main diagram should look like the following:
You did not create a service contract for the Purchasing service interface; later, you use a services architecture to specify additional details about the Purchasing service.
In the next lesson, you create the participants that interact with the application services.