Concept: Business Use-Case Realization |
A use-case realization represents how a use case will be implemented in terms of collaborating objects. This guideline describes its purpose and UML notation.
Relationships
Related Elements | Business Analysis Model Business Design Model Business Model Business Use Case Model a Scenario
Main Description
A business use-case realization describes how a Business Use Case is performed within an organization in terms of collaborating elements. Business use-case realizations are described from an internal (white box) perspective. A realization can be thought of as the "machinery" or inner workings that allows an organization to perform a business use case. Realizations are usually maintained in the Artifact: Business Model. Realizations help team members understand how the business is structured and operates in order to: Identify and prioritize organizational improvement Identify roles, responsibilities, and information the organization requires, based on the the requirements in the business use cases Determine the effects of organizational changes due to process automation or outsourcing Gain understanding of how software and other systems can fit into the organization The Business Use-Case Realization may include, for example, a textual description (a document), class diagrams of participating classes and subsystems, and sequence diagrams that illustrate the flow of interactions between elements inside the business. The reason for separating the use-case realization from its use case is so business use cases can be managed separately from their realizations. This is particularly important for larger projects, or of organizations where the same business use cases are used to define different to-be business processes. In a model, a use-case realization is represented as a UML collaboration that groups the diagrams and other information (such as textual descriptions) that form part of the use-case realization. UML diagrams that supports business use-case realizations can be produced in an analysis context, a design context, or both, depending on the needs of the project. For each use case in the use-case model, there can be a use-case realization in the analysis/design model with a realization relationship to the use case. In UML this is shown as a dashed arrow, with an arrowhead like a generalization relationship, indicating that a realization is a kind of inheritance, as well as a dependency. #### Class Diagrams Owned by a Use-Case Realization For each business use-case realization there can be one or more class diagrams depicting its participating elements. A business elements often participate in several use-case realizations. #### Sequence Diagrams Owned by a Use-Case Realization For each business use-case realization there can be one or more interaction diagrams depicting its participating business elements their interactions. Sequence diagrams show the explicit sequence of messages between elements and are better when it is important to visualize the time ordering of messages.Realizing use cases through interaction diagrams helps to keep the design simple and cohesive. Assigning responsibilities to elements on the basis of what the business use-case scenario explicitly requires encourages the business model to contain the following: Only the behavior actually used in support of a business use case scenario Behavior that can be verified through observation or some other means. Business behavior that is more easily traceable to requirements and changes Explicitly declared dependencies that are easier to manage
More Information
Concepts | Business Use Case
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