What is a_use_case


Published on

Published in: Business, Economy & Finance
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide

What is a_use_case

  1. 1. ?What Is A Use Case a usage case is simply a reason to use a System For example ,a bank cardholder might need to use . an ATM to get cash from their account .It s as simple as that
  2. 2. The purpose of use case diagram So in brief, the purposes of use case diagrams can be as follows:  Used to gather requirements of a system (analysis phase).  A Use Case represents a discrete unit of interaction between a user (human or machine) and the system  describing a system from external usage viewpoint not developer's perspective.  Identify external and internal factors influencing the system.
  3. 3. Use case diagram components System boundary: indicates the scope of your system. Anything within the box represents functionality that is in scope and anything outside the box is not boundary . Use case: Actor use case relatio n Deposit cash cardHolder Actor: An actor is a person, organization, or external system that plays a role in one or more interactions with your system relation: To connect between the object (communication) A use case describes a sequence of actions that provide something of measurable value to an actor
  4. 4. Actor    The actor describes a role not person Actors don t have to be people. They can be other systems. For example, the ATM may need to connect to the cardholders bank There are two kinds of actor - primary and secondary.   Primary actor is anyone or thing that interacts with the system to gain direct benefit. Secondary actor is anyone or thing that involve in achieving a use case yet, they do not gain direct benefit from the system. Very often, secondary actor is someone who assist the primary actor to achieve a use case.
  5. 5. (Use case (base    Deposit cash The goal must be of value to the actor . ( enter PINs( don t build ATM s just so people can enter their PINs A use case is an objective user(s( wants to achieve with a system. Use cases are named with : verb or verb + noun phrase.
  6. 6. ( Continuous ….. use case(basic Tip for use case    simple title and describe the user goal Verbs like 'do' and 'perform' and nouns like 'data' and 'information' should be avoided whenever possible. It is intended to provide an overview of what the user want without knowing how to achieve the goal Deposit cash
  7. 7. (Continuous ….. use case( not basic  The <<include>> use case means that the flow of that use case is always included  But a <<extend>> use case means that the flow of the extending use case is only included under specific conditions
  8. 8. (Continuous ….. use case( not basic
  9. 9. Example of wrong use cases
  10. 10. Example of wrong use cases
  11. 11. Example of wrong use cases
  12. 12. conclusion the key questions we need to ask are; who will be using the system, and what will they be using it to do?  Be one of the smart 1% and always remember that use case designs aren t the same thing as requirements  Do not try to include all types of relationships. Because the main purpose of the diagram is to identify requirements. 
  13. 13. ..……… Thank you Written by : noor alshiyab 