Hi

Can someone tell me What is the actual usage of Include and Extend  usecases for programmers & analyst.

As of now I'm using extend use case to document the alternate flow , is this right ? please suggest.

and

Include to document those usecase which contain (Use) the behavior of other usecase.

Actually, I wish to know how & what programmers understand from these use cases & how there coding or development get affected by using these usecases.

Regards,

Raj.

Hi Raj,

I'm going give you the quick answer and will let Perry follow up with the more extensive one:

• Includes & Extends refer to two ways of referencing/specifying that functional behavior in one is used/triggered by another use case.
• The include is generally used when the behavior specified in the included use cases is needed by the main use case to accomplish its goal under a given scenario.
• The extend is generally used when the behavior specified in the extending use case is optional and does not have an impact on the goal if the use case being extended.
• Include example: If "Authenticate Customer" is the use case which checks the credentials of a customer at an ATM machine, then this could very well server as an included use case for a  "Withdraw Money" use case.  Since the authentication process is required in order to Withdraw Money, the "Authenticate Customer" will be shown as an include.
• Extend example: However, if another use case exists called "Print Receipt", this might be used to extend the "Withdraw Money" use cases since this could be an optional step.  That is I can successfully withdraw money without needing or printing a receipt.

- Adrian