iGATE: An Introduction to UML
iGATE: An Introduction to UML
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UML-Introduction
UML-Introduction
UML - Unified Modeling Language.
The model abstracts the essential details of the
underlying problem in a diagrammatic way.
Solution to an object-oriented problem lies in the
construction of a model.
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Some terminologies…..
Some terminologies…..
Domain - Actual world from which the problem comes.
Model - An abstraction of the underlying problem.
Objects - Models consist of objects that interact with each
other.
Messages - Interaction between objects is through
messages.
Attributes - Data of an object.
Behaviors - Methods or functions of an object telling what it
can do.
Classes - Wraps attributes behaviors into a single distinct
entity.
Instances - Objects are instances of classes.
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ModelingDiagramsinUML
ModelingDiagramsinUML
•Use case diagrams
•Class diagrams
•Object diagrams
•Sequence diagrams
•Collaboration diagrams
•State chart diagrams
•Activity diagrams
•Component diagrams
•Deployment diagrams
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1.UseCaseDiagrams
1.UseCaseDiagrams
Use case diagrams describe what a system does from
the standpoint of an external observer. The emphasis is
on what a system does rather than how
Use case diagrams are closely connected to scenarios.
A scenario is an example of what happens when
someone interacts with the system.
A use case is a summary of scenarios for a single task
or goal. It is the key system behavior of the system. An
actor is who or what initiates the events involved in that
task.
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