Writing effective use case tutorial

1. We first create actors using the Actors Grid. Select Tools > Model Element Grid > Open Actors Grid.
   

   Open actors grid

2. Click the Create Actor button at the top left hand corner to create new actor.
   

   Create actor

3. Name the actor as Order Process Clerk, the documentation of the actor can be specified directly in the Documentation pane.
   

   Input "Order Processing Clerk" to actor name cell and input documentation

4. Create two more actors, Customer Service Assistant and Inventory Control Clerk. Besides clicking the Create Actor button, you can press the Insert key to insert a new actor.
   

   Create two more actors

1. After creating actors, we now switch to create use cases. Select Tools > Model Element Grid > Open Use Cases Grid.
   

   Open use cases grid

2. Similar to the Actors Grid, you can create use case with the Create Use Case button at the top left hand corner of the grid.
   

   Create use case

3. Name the use case as Place Order.
   

   Input "Place Order" to use case name cell

4. Let's create few more use cases, Check Order Status, Process Order, Schedule Delivery and Handle Goods Return.
   

   Create 5 more use cases

1. We can define the details of a use case using the use case detail editor. Select the Place Order use case, and then click the Open Use Case Detail button.
   

   Click the "Open Use Case Detail" button to open use case detail

2. We first switch to Info tab, and specify the Rank of the use case as High, and fill in the brief description in the Documentation field.
   

   Change use case rank to "High"

3. Switch to Flow of Events tab, and then specify the flow of events of the use case.
   

   Switch to "Flow of Events" pane and input the flow of events

4. Switch to Details tab and specify more detail, such as Preconditions and Post-conditions for the use case.
   

   Switch to "Details" tab

5. Go back to Use Case Grid by clicking the Go to Grid button at the top right hand corner of Use Case Details editor.
   

   Click on the "Go to Grid" button

1. After we define the details of the use case, we can now put it into diagram. Select the Place Order use case in the Use Case Grid, and press the Visualize button.
   

   Click on the "Visualize" button to show the selected use case to diagram

2. Let's visualize the Place Order use case in a new use case diagram. Select Create new diagram and leave the name as default in the Visualize Model Element dialog. Press the Create button to proceed.
   

   The Visualize Model Element dialog box

3. Open Model Explorer, and drag the Customer Service Assistant actor to the newly created use case diagram.
   

   Drag and drop "Customer Service Assistant" model element to use case diagram

4. Since the actor is not appearing on any diagram yet, you will be prompted to specify it as Master View in the project.
   

   "Set as Master View" prompt box

5. Connect the actor and use case by selecting the Association icon from actor, and drop it on the use case.
   

   Connect "Customer Service Assistant" actor to "Place order" use case

6. Open the use case detail again by right click on the use case, and select Use Case Details.
   

   Open use case detail pane

7. You can see the Customer Service Assistant now being specified in the Primary Actors field.
   

   "Place Order" use case detail

8. The supporting actors can be specified by pressing the + button next to Supporting Actors field, and select the actor from the list.
   

   Click on the "Add Primary Actor" button

9. Let's create an extended use case from Place Order, name it as Process Out of Stock Order. Name the extension point as Out of Stock.
   

   Create extend use case

10. After that enter the documentation of the Process Out of Stock Order use case.
    

    Use Case Specification dialog box

1. Switch back to the flow of events of Place Order use case. Let's add an extension for step 5 of the flow of events. Select step 5, then press the New Extension button.
   

   Create extension point by "New Extension" button

2. The extended use case will be listed in the combo box in the Extension table. Let's select the Out of Stock use case.
   

   Select "Process Out of Stock" extension point

3. The Out of Stock use case is now listed as the extension for step 5. Move your mouse cursor over it and the documentation of the Out of Stock use case will be shown.
   

   "Process Out of Stock" hyperlink

4. You can jump to the Out of Stock use case or open its flow of events by right clicks on it.
   

   Jump to extend use case by popup menu

Resources

1. sales_order_system.vpp

Related tutorials

• Constructing Use Case Model from Glossary
• Activity diagram generation by use case flow of events
• Identify use cases from business process