The IS Development Funnel UML SDLC Systems Development

The IS Development ‘Funnel’ – UML

SDLC – Systems Development Life Cycle In IST-110 you learned about the SDLC.

Where does the UML fit? The UML is used in the analysis and design phases of the SDLC.

What is the UML? The Unified Modeling Language (UML) is a means of diagramming how a system operates. It is the graphical notation used to express system design and operation.

UML Components Most of the systems components in UML can be broken down into 2 main categories of components: static components and dynamic components. Static components are used to represent the static views of a system, mainly the classes. The classes, which also show the object-orient nature of the UML, are used to represent the objects that exist in a system. Dynamic components are used to represent the dynamic views of a system, mainly the point of view of the users of the system and how they see it.

Static UML Components Static components of a system are represented in UML as classes. Classes, as you remember from IST-230, are types containing data. Classes contain functions (functions may manipulate data, perform a computation, make a query or monitor an object for the occurrence of an event).

UML Classes Here is an example of a UML class.

Dynamic UML Components Dynamic components of a system are represented in UML as use case diagrams. Use case diagrams are used to illustrate how the system is used. Another way to think of the use case is as a collection of scenarios about system usage.

UML Use Cases In this example of a Library Information system, ‘A’ represents the system boundary which in this case is a generalized view of the info system. ‘B’ and ‘C’, called actors, represent the users in the info system and how they interact with the system.

How is the UML Used in Systems Development? UML is used to communicate both with developers and users and is used throughout the SDLC design and analysis phases. It can also be used to assist in documenting the system.