use case senario
Use Case Senario Based Diagram
A Use Case Model describes the proposed functionality of a new system. A Use Case represents a discrete unit of interaction between a user (human or machine) and the system. This interaction is a single unit of meaningful work, such as Create Account or View Account Details.
Each Use Case describes the functionality to be built in the proposed system, which can include another Use Case's functionality or extend another Use Case with its own behavior.
A Use Case description will generally includes:
General comments and notes describing the use case.
Requirements - The formal functional requirements of things that a Use Case must provide to the end user, such as . These correspond to the functional specifications found in structured methodologies, and form a contract that the Use Case performs some action or provides some value to the system.
Constraints - The formal rules and limitations a Use Case operates under, defining what can and cannot be done. These include:
Pre-conditions that must have already occurred or be in place before the use case is run; for example, must precede
Post-conditions that must be true once the Use Case is complete; for example,
Invariants that must always be true throughout the time the Use Case operates; for example, an order must always have a customer number.
Scenarios – Formal, sequential descriptions of the steps taken to carry out the use case, or the flow of events that occur during a Use Case instance. These can include multiple scenarios, to cater for exceptional circumstances and alternative processing paths. These are usually created in text and correspond to a textual representation of the Sequence Diagram.
Scenario diagrams - Sequence diagrams to depict the workflow; similar to Scenarios but graphically portrayed.
Additional attributes, such as implementation phase, version number, complexity rating, stereotype and status.
Actors
Use Cases are typically related to
A Use Case Model describes the proposed functionality of a new system. A Use Case represents a discrete unit of interaction between a user (human or machine) and the system. This interaction is a single unit of meaningful work, such as Create Account or View Account Details.
Each Use Case describes the functionality to be built in the proposed system, which can include another Use Case's functionality or extend another Use Case with its own behavior.
A Use Case description will generally includes:
General comments and notes describing the use case.
Requirements - The formal functional requirements of things that a Use Case must provide to the end user, such as . These correspond to the functional specifications found in structured methodologies, and form a contract that the Use Case performs some action or provides some value to the system.
Constraints - The formal rules and limitations a Use Case operates under, defining what can and cannot be done. These include:
Pre-conditions that must have already occurred or be in place before the use case is run; for example, must precede
Post-conditions that must be true once the Use Case is complete; for example,
Invariants that must always be true throughout the time the Use Case operates; for example, an order must always have a customer number.
Scenarios – Formal, sequential descriptions of the steps taken to carry out the use case, or the flow of events that occur during a Use Case instance. These can include multiple scenarios, to cater for exceptional circumstances and alternative processing paths. These are usually created in text and correspond to a textual representation of the Sequence Diagram.
Scenario diagrams - Sequence diagrams to depict the workflow; similar to Scenarios but graphically portrayed.
Additional attributes, such as implementation phase, version number, complexity rating, stereotype and status.
Actors
Use Cases are typically related to