UML War Needs analysis read Note 04

Learning the preceding UML diagrams does not meet the modeling of all situations, such as when a flowchart involves multiple roles, and by interacting with multiple roles, a sequence diagram is an option. The sequence diagram is similar to the spoken language of Chinese grammar, which describes the sequence in which an event occurs. Sequence diagram is divided into two kinds of syntax: loop and branch grammatical structure. It emphasizes the order of precedence.

As a developer, not only to know how to get useful information from users, but also to understand how to clearly describe their own ideas, to give customers a complete structure, full-featured system prototype. Then, these necessary drawing techniques will help a lot. Business use cases can capture requirements throughout the software development process, and serve as a guide to other workflow processes throughout the project development process. The business process of the system is clearly understood by the business use case description of the system in the process of the machine. Another UML diagram is involved in this process: use case diagrams.

Use case diagrams can express the needs of the system from a relatively clear starting point, and do not involve technical terminology. Use case diagrams and other UML work together to be efficient. It focuses on the diagram of what role can be done by a system, and the use case diagram focuses on the external performance of the system, the interaction of the system with the human, and the interaction of the system with other systems. First a villain in the use case diagram represents a character. A role is an abstraction of the user of a system. A character can represent a number of specific people, both as performers and as things that interact with the system. What the system should do is to describe a use case in a "dynamic" form. Several use cases can be executed by multiple performers. At all, there should be a system boundary in the outer layer of the use case diagram, with only use cases within the system boundary and no performers. and to see them connected is the relationship. But not all use case diagrams need to draw system boundaries, so it is common practice to use a global case diagram to represent the system's requirements in a macroscopic way, such that a macro use case diagram needs to draw a system boundary. The relationships of roles in a use case diagram include inheritance, include, Extend (extensions). Prior to the development of the system, the use case diagram was identified and the business process was determined.

Of course, use case diagrams are not omnipotent and are not the only way to express demand. Learn to master the use case diagram to carry out the demand analysis method, can be flexible application is the key.

UML War Needs analysis read Note 04