How to Use Textual Analysis?

OTV is a company which delivers online TV broadcasting services. It is going to improve its services by re-developing the online broadcasting system. In this tutorial, we will make use of textual analysis to identify main use cases of OTV's online broadcasting services, and form a use case diagram for further studies.

February 3, 2016
Views: 106,285
PDF Download
  1. Download the attached document file OTV.txt, which describes the general business operations of OTV in advance.
  2. Create a new project by selecting Project > New from the application toolbar. In the New Project window, enter OTV as the project name and click Create Blank Project.
  3. Select Diagram > New from the application toolbar.
  4. In the New Diagram window, select Textual Analysis and click Next.
    new textual analysis
  5. Click OK again to create a problem statement.
  6. You can enter the problem statement in the problem statement editor. Choose either to type directly there or import a text file. Let's try to import the downloaded text file. Click on the button Import File, select OTV.txt, and click the Open button.
    import file
  7. The text is imported. Study the problem statement.
    imported text
  8. Now, identify all candidate actors that are involved in the system. By reading the problem statement, we find the first candidate actor, premium member, in the second paragraph. Highlight and then right-click on it, and select Actor from the pop-up menu.
    add first actor
  9. Check out the grid at the bottom. It lists the properties of the extracted candidate object: Candidate Class (candidate object's name), Extracted Text (the word/phrase it extracted from), Type (candidate type), Description, Occurrence (the number of times the word/phrase appears in the problem statement), and Highlight (the highlight color of the candidate object).
    actor created
  10. The second candidate actor, general member, is found. Again, add it as a candidate actor.
    add second actor
  11. In the last paragraph, we find the candidate actor administrator. Add the text administrators as an actor.
    add last actor
  12. Now, identify candidate use cases. Candidate use cases usually appear as a verb or verb + noun phrase. For instance, "watch any archived TV programs" in the second paragraph. Highlight and right-click on "watch any archived TV programs", and select Use Case from the pop-up menu.
    add usecase
  13. Search the text below and identify them as candidate use cases:
    Register as a general member
    Register as a premium member
    Watch both archived and live programs
    Upgrade himself to a premium member
    Remove his/her account
    Posting their opinion
    Receive monthly newsletter
    Update the program schedule
    Update the program
    Archive programs
    Monitor the delivery of newsletter
  14. To distinguish the candidate objects in the problem statement, we can change their highlight color. Let's select orange as the highlight color for candidate actors. Click the Highlight cell of the premium member and press the inverted triangle. Select orange from the combo box.
    change color
  15. You may notice that some of the candidate actors and use cases can be renamed to make them shorter and more informative. Take candidate actor premium member as an example. To rename a candidate actor, in the grid at the bottom, double-click on the premium member cell under Candidate Class and change it to Premium Member.
    rename
  16. On the other hand, you can enter a description for Premium Member. The text you type in the Description cell will become the documentation of the Premium Member actor. For example, enter "A premium member can watch both archived and live TV programs for US $30 per month."
    enter description
  17. Rename the other candidates and their descriptions as shown below:
    Candidate Class Extracted Text Description
    General Member general member A general member can only watch archived TV programs. To watch live programs, s/he should upgrade his/her membership to a premium member.
    Administrator administrators The administrator has the rights to update the TV program schedule, update, and archive TV programs. S/He is responsible for mentoring the delivery of the newsletter to premium members.
    Watch Archived Program watch any archived TV programs Members can watch the scheduled archived TV programs anytime.
    Register as General Member register as a general member It is free of charge to register as a general member.
    Register as Premium Member register as a premium member No application fee is applied for registering as a premium member.
    Watch Live Program watch both archived and live programs Only premium members are allowed to watch live TV programs.
    Upgrade Membership upgrade himself to a premium member A general member can upgrade his/her membership to a premium member.
    Remove Account remove his/her account US$50 of administrative fee is applied when premium members remove their account.
    Post Opinion posting their opinion Premium members can post their opinion regarding TV programs on OTV's official website.
    Receive Newsletter receive monthly newsletter Premium members can subscribe to a monthly newsletter for US$300 per annum.
    Update Program Schedule update the program schedule The administrator keeps updating the TV program schedule fortnightly.
    Update Program update the program The administrator keeps updating TV programs weekly.
    Archive Program archive programs The administrator keeps archiving TV programs weekly.
    Monitor Delivery of Newsletter monitor the delivery of newsletter The administrator is responsible for monitoring the delivery of the newsletter.

    Up to now, the textual analysis should look like this:
    completed
  18. Let's switch to the candidate pane by clicking the Candidate Pane View button. The candidate pane view is where you can visualize candidate objects for easy arrangement.
    candidate pane
  19. We are going to form a use case diagram with those candidate objects. Create a use case diagram first. Select Diagram > New from the application toolbar. In the New Diagram window, select Use Case Diagram and click Next. Then, click OK to create the diagram.
  20. Open the Model Explorer. Select View > Panes > Model Explorer from the application toolbar.
  21. Select all the candidate actors and use cases. Then, drag them onto the diagram.
    select candidate actors and use cases
  22. Rearrange the shapes to make the diagram similar to the image below:
    basic use case diagram
  23. Associate actors with use cases. Finally, the diagram should look like the following:
    final ucd
  24. Save the project. This is the end of the tutorial.