Use case realizations are collaborations that group all of the IT elements required to realize a use case. A UCR contains numerous diagrams depicting the architectural assets involved in the realization. These diagrams contain model elements that have been created in their appropriate locations within the architectural views. The diagrams should focus on the changes needed to realize the use case being modeled. Sometimes, nothing is being changed in a particular diagram, and a link to a diagram in another location, e.g. in a previous version of the UCR, may be used.
The following sections describe the different types of diagrams used for a use case realization.
Application Context Diagram
Content
Component Structure Diagram
This diagram type is used to model the structural connections among applications, services, and databases as required by a given scenario related to a Use Case Realization or a Vertical Slice. It uses the (EA)<sup>2</sup> Application Architecture Component Toolbox. The Application Component Diagram shows how application, services, and databases communicate with each other to satify the requirements of the scenario. All of the components shown on this type of diagram are created under their respective architectural views. They were not created on this diagram or they would be placed in the wrong location in the Project Browser. However, the exposed interfaces and the connectors can be created here.
Before creating new exposed interfaces, first make sure that the one you need is not already available. Do this by right clicking on the component and then selecting Embedded Elements / Emebbed Elements… You will see all of the embedded elements. Those that appear on the diagram will be checked. If you find the one you need, simply check it and then click Close. If it is not there, close the dialog and then drag the appropriate type of exposed interface from the (EA)<sup>2</sup> Application Component Toolbox onto the component. Look for the name of the interface in the drop down box.
Component Integration Diagram
Content
Behavior Diagram
This diagram shows the sequence of interactions between the components from the associated Application Structure Diagram. The elements across the top are instances of the components (Business Apps, System Apps, and EDB Schemas) from the Application Structure Diagram. They are created by dragging each element from the project browser while holding down the [Control-key]. To get the interfaces that you see participating in the flow, right click on the elements and select Embedded Elements / Embedded Elements... from the context menu. Check the Exposed Interface(s) that you need, click OK, and the resize the element and its Exposed Interfaces as needed.
Next, use the Quick Link on the lifelines to draw the connectors (referred to as messages). You can have textual descriptions added to the left side of the diagram that following any changes in the position of their related message. To do so, double click on the message to be documented and add the text in the Contraints box.
