In the Unified Modelling Language (UML), a Use Case is a concept, a way of thinking about a problem The problem is described (or better: depicted) by means of actions between actors
A use case is a description of how end-users will use a software code It describes a task or a series of tasks that users will accomplish using the software, and includes the responses of the software to user actions Use cases may be included in the Software Requirements Document (SRD) as a way of specifying the end-users' expected use of the software
A specific way of using the system by performing some part of the functionality Each use case constitutes a complete course of action initiated by an actor, and it specifies the interaction that takes place between an actor and the system The collected use cases specify all the existing ways of using the system
One of the models supported by the Unified Modelling Language (UML), a use case provides a snapshot model of a set of system behaviour that meets a user goal A use case represents a functional requirement, showing what happens, but not how it is achieved by the system
a general way of using a blackbox business, application, component, or framework to achieve a goal of some external, primarily specified in terms of its normal and exceptional use case paths Contrast with usage scenario and use case path Contrast with change case and misuse case For example, the use cases for an automatic teller machine application could include customer deposits funds, customer withdraws funds, customer obtains account balances, customer transfers funds, and customer makes payment Note that a use case is a single, complete functional abstraction
A description of system behaviour, in terms of sequences of actions A use case should yield an observable result of value to an actor A use case contains all alternate flows of events related to producing the "observable result of value" More formally, a use case defines a set of use-case instances or scenarios
A description of a process by which actors do things that lead to the need for information interchange Use cases may break down into component use cases A use case may appear as a component in several other use cases When a use case contains component use cases, the order in which they occur is not specified See scenario
Amethodology used in system analysis to identify, clarify, and organize system requirements The use case is made up of a set of possible sequences of interactions between systems and users in a particular environment and related to a particular goal It consists of a group of elements (for example, classes and interfaces) that can be used together in a way that will have an effect larger than the sum of the separate elements combined The use case should contain all system activities that have significance to the users
A use case is a named collection of classes, interfaces, and other elements that work together to provide some behavior that is bigger than the behavior represented by the sum of the parts This behavior yields an observable result of value to one or more actors A use case always has one main flow of events (also known as a basic course of action, and will generally have at least one exceptional flow of events (or alternate course of action
A description of a single interaction between a user and an entity A technique used by a designer to identify requirements on the entity Includes preconditions and postconditions @@
A transaction with the system from interface to interface initiated by the user or another system The use case captures the essence of a single, simple system responsibility and is the basis for object-oriented modeling Use cases are used to detail requirements, drive testing, and validate the object model
A use-case model consists of actors, use cases, and relations among them Actors represent everything that must exchange information with the system, including what are typically called users When an actor uses the system, the system performs a use case A good use case is a sequence of transactions that yields a measurable result of value for an actor The collection of use cases is the system's complete functionality [go to site]
A typical interaction between a user (or agent) and a computer system It captures some function visible to the user The use case achieves a goal for the user