Classification of UML Diagrams - ppt download
Each use case represents a unit of useful functionality that subjects provide to actors. An association between an actor and a use case indicates that the actor. We used the below table to identify the Actors and the Use Cases for the system. Following diagram shows the overall view of the Ticket Booking System for . The following diagram depicts the relationships between the. The actors are external to the system but interact with it. A common So the theater ticket use case diagram could also apply to Amtrak ticket sales. However .
Use cases are typically initiated by a user to fulfill goals describing the activities and variants involved in attaining the goal. Relationship The relationships between and among the actors and the use cases.
System Boundary The system boundary defines the system of interest in relation to the world around it. Benefits of Use Case Diagram Use cases is a powerful technique for the elicitation and documentation of black-box functional requirements.
Because, use cases are easy to understand and provide an excellent way for communicating with customers and users as they are written in natural language. Use cases can help manage the complexity of large projects by partitioning the problem into major user features i.
A use case scenario, often represented by a sequence diagram, involves the collaboration of multiple objects and classes, use cases help identify the messages operations and the information or data required - parameters that glue the objects and classes together.
Use cases provide a good basis to link between the verification of the higher-level models i. Use case driven approach provides an traceable links for project tracking in which the key development activities such as the use cases implemented, tested, and delivered fulfilling the goals and objectives from the user point of views.Use Case Diagram: Actors - Georgia Tech - Software Development Process
How to Draw a Use Case Diagram? A Use Case model can be developed by following the steps below. Identify the Actors role of users of the system. For each category of users, identify all roles played by the users relevant to the system.
Use Case Diagram Tutorial
Identify what are the users required the system to be performed to achieve these goals. Create use cases for every goal. Structure the use cases. Prioritize, review, estimate and validate the users. Draw packages for logical categorization of use cases into related subsystems. You can now look at the Use Cases and identify common sequences of user-system interaction.
Abstract and generalized Use Case The general use case is abstract. It can not be instantiated, as it contains incomplete information. Is the execution of this use case conditional? Does this use case change the behavior of the base use case? Included use case Extending use case No Yes [ Source: I am the manager of a theatre. I want to create an automated movie ticket machine.
Use Case Diagram Tutorial
You are analysts who need to describe what the customer wants as a set of use cases Simplifying assumptions: What are the use cases goals of actors? Why three use cases for Customer? Which use cases look easy to write 40 Use cases for Manager Use case: Set title Use case: Manager requests a change of movie title 2.
Machine asks manager for new movie title 3. Manager enters movie title Use case: Manager requests a change of ticket price 2. Machine asks manager for new price for movie title 3.
Manager enters ticket price Alternatives: Machine asks manager to reenter price Use case: Manager requests a change in number of seats 2.
Machine asks manager for number of seats in theatre 3. Manager enters number of seats Alternatives: Invalid number of seats If manager enters number less than 20 or greater than 3a. Machine asks manager to reenter number of seats 41 Use cases for Customer Use case: Customer requests tickets 2. Machine tells customer to put balance due in money slot 3.
Customer enters money in money slot 4.
Classification of UML Diagrams
Machine updates customer balance 5. Customer requests tickets 6.
Machine prints tickets 7. Machine updates number of seats Alternative: Insufficient seats At step 1, if number of tickets requested is less than available seats, 1a.
Display message and end use case Alternative: Display insufficient amount entered 5b. Go to step 3 42 Behavioral Diagram II Sequence Diagram 43 Interaction Diagrams One of the subsets of Behavioral diagrams wherein Interaction diagrams graphically depicts the way objects interact with each other to give different behaviors.