Search results
Results from the WOW.Com Content Network
The diagram emphasizes events that cross the system boundary from actors to systems. A system sequence diagram should be done for the main success scenario of the use case, and frequent or complex alternative scenarios. There are two kinds of sequence diagrams: Sequence Diagram (SD): A regular version of sequence diagram describes how the ...
In software and systems engineering, a use case is a potential scenario in which a system receives an external request (such as user input) and responds to it. A use case is a list of actions or event steps typically defining the interactions between a role (known in the Unified Modeling Language (UML) as an actor) and a system to achieve a goal.
A use case diagram [1] is a graphical depiction of a user's possible interactions with a system. A use case diagram shows various use cases and different types of users the system has and will often be accompanied by other types of diagrams as well. The use cases are represented by either circles or ellipses. The actors are often shown as stick ...
System context diagrams are used early in a project to get agreement on the scope under investigation. [4] Context diagrams are typically included in a requirements document. These diagrams must be read by all project stakeholders and thus should be written in plain language, so the stakeholders can understand items within the document.
CRC card sessions may be followed by the creation of sequence diagrams to capture interactions that are identified. CRC cards are frequently employed during the design phase of system and software development to transition use-case descriptions into class diagrams, allowing a smoother transition with a greater overview and permitting developers ...
UML diagrams used to represent the physical view include the deployment diagram. [2] Scenarios: The description of an architecture is illustrated using a small set of use cases, or scenarios, which become a fifth view. The scenarios describe sequences of interactions between objects and between processes.
Use case analysis is a technique used to identify the requirements of a system (normally associated with software/process design) and the information used to both define processes used and classes (which are a collection of actors and processes) which will be used both in the use case diagram and the overall use case in the development or redesign of a software system or program.
Examples of such operations are requesting a read operation, reading, writing, aborting, committing, requesting a lock, locking, etc. Often, only a subset of the transaction operation types are included in a schedule. Schedules are fundamental concepts in database concurrency control theory. In practice, most general purpose database systems ...