First knowledge of UML

Labels: UML Visualization

UML, full name: Unified Modeling Language, unified modeling language. It is a standard modeling language for software and system development. It mainly analyzes and designs the system in a graphical manner. At the same time, UML is neither a programming language nor a formal language, but a visual modeling language.

From the diagram, we can basically understand the basic concepts of UML, the most important of which is the relationship and diagram in the basic structure.

Relationship: represents the relationship between basic symbols or things.

Association: represented by a horizontal line

Dependency: add an arrow to the dotted line to indicate the dependency between items. The arrow points to the dependent object.

Generalization: a line is composed of a hollow triangle frame. It can also be called inheritance.

Implementation: The dotted line is added with a hollow triangle, and the class is at the dotted line end.

Drawing can be said to be the most important module. UML is to make developers better understand the program to be developed through drawing. Therefore, drawing is the focus and difficulty of our learning. First, we will briefly introduce the basic concepts of each graph:

Use case diagram: used to describe the user's needs, describe the system's functions from the user's perspective, and point out the executors of the Functions

Class diagram: defines the class in the system, including describing the internal structure of the class and the relationship between the class. Class diagrams are mainly used to describe the static structure of the system.

Object graph: an instance of a class graph that describes the objects contained by the system at a specific time point and the relationships between objects.

Status chart: Describes all possible states of the Class Object and transfer conditions of the State when an event occurs.

Activity diagram: used to describe the activities that meet the requirements of use cases and the constraint relationships between activities. It is used to identify parallel activities of the system.

Sequence diagram: Describes the interaction sequence between objects.

Collaboration diagram: partnerships between objects

Component diagram: physical structure of code components and dependencies between components

Deployment diagram: defines the physical architecture of hardware in the system, which is used to describe the actual physical devices and their connection relationships.

We are still watching the video of UML. We need to learn more about it. However, with this open-door learning, I can deeply feel that the preparation of the documents we learned previously is a stepping stone for us to step into a higher position by programmers, this allows us to pay attention to the details that we did not pay attention to when writing code. The learning of UML is to help us better understand the software we want to develop. In addition, it can also be understood by those who do not understand programming. The more you learn, the higher you will feel. In this case, work hard, fighting...

I was just getting started with UML, but I still don't know much about it. If you have any shortcomings, I hope you can give us some guidance and make common progress.

First knowledge of UML