Shulou(Shulou.com)06/02 Report--

This article mainly introduces the relationship between UML use case diagrams, which has a certain reference value, interested friends can refer to, I hope you can learn a lot after reading this article, let the editor take you to understand it.

UML use case diagram

I. concept

The UML use case view divides system functionality into requirements that are useful to participants (that is, ideal users of the system). The interaction part is called the use case. Use cases use a series of messages between the system and one or more participants to describe interactions in the system.

The use case view contains six elements, namely: actor (Actor), use case (UseCase), relevance (Association), inclusion (Include), Extend (Extend), and generalization (Generalization).

II. Participants

The actor is an entity outside the system that participates in the execution of the use case in some way. Each participant can participate in one or more use cases. It interacts with the use case by exchanging information, while the internal implementation of the actor is irrelevant to the use case. There are three main categories of participants: system users, other systems that interact with the system being built, and processes that can be run.

3. UML use case diagram relationship

1. Association: the association represents the communication between the participant and the use case, represented by arrows.

2. Inclusion relationship: a use case in the UML use case diagram can simply contain the behavior that other use cases have, and take the use case behavior it contains as part of its own behavior, which is called the inclusion relationship. In UML, the inclusion relationship is represented by a dotted arrow with the word "include" pointing to the included use case. The inclusion relationship separates the common steps of several use cases into a separate included use case. The included use case is called the provider use case, and the included use case is called the customer use case.

Extension relationship: a use case can also be defined as an incremental extension of the underlying use case, which is called an incremental extension. In UML, the extension relationship is represented by a dotted arrow plus the word "extend". The arrow points to the extended use case (that is, the underlying use case).

4. Generalization relationship: a use case in a UML use case diagram can be specifically enumerated as one or more sub-use cases, which is called use case generalization. When the parent use case can be used, any child use case can also be used. Generalization relationships in UML use a triangular arrow to point from the child use case to the parent use case.

Thank you for reading this article carefully. I hope the article "what is the relationship between UML use case diagrams" shared by the editor will be helpful to you. At the same time, I also hope that you will support us and pay attention to the industry information channel. More related knowledge is waiting for you to learn!

Welcome to subscribe "Shulou Technology Information " to get latest news, interesting things and hot topics in the IT industry, and controls the hottest and latest Internet news, technology news and IT industry trends.