Activity diagrams describe the actual work flow behavior of a system in Information Technology. These diagrams are very similar to state Diagrams because activities are the actual state of doing something. These diagrams describe the actual state of activities of a system by showing all the sequence of activities performed. Also, these diagrams can show activities that are conditional or parallel.
When to Use: Activity Diagrams
Activity diagrams should be used in alignment with other modeling techniques like interaction diagrams and State diagrams. The main reason behind using these diagrams is to model the work flow behind the system being designed. these Diagrams are also useful for analyzing a use case by describing what actions need to take place and when they should occur, describing a complicated sequential algorithm and modeling applications with parallel processes.
Activity diagrams’ advantages:
- UML modeling language included that these diagrams are normally easily comprehensible for both analysts and stakeholders.
- In UML for the IT Business Analyst, “The activity diagram is the one most useful to the IT BA for depicting work flow [because] it is simple to understand-both for BAs and end-users.”
- Since they are among the most user-friendly diagrams available, they are generally regarded as an essential tool in an analyst’s repertoire.
- Additionally, as stated above, activity diagrams allow an analyst to display multiple conditions and actors within a work flow through the use of swimlanes. Swimlanes, however, are optional as a single condition or actor is normally displayed without them.
Activity diagrams’ disadvantages:
UML modeling language include that these diagrams have the potential to become overly complex because their user-friendly nature may lend itself to an all-inclusive description. In other words, since it is so simple to display the information related to the project, why not include all of it? When an analyst has a large project, creating a single, overly complex diagram can be a temptation.
However, as one author notes, “if you are using activity diagrams to define the structure of a work flow, you should not attempt to explore several levels of activity graphs down to their most ‘atomic’ level”. Instead, an analyst should try to present a new diagram for each work flow, or if more applicable, to use swimlanes to present different actors within the same work flow.
Another aspect of these diagrams is that they may not be used in lieu of a state diagram or sequence diagram because “activity…