Nine types of UML diagrams

Labels: UML, nine types of graph analysis

UML, as a design tool, focuses on practice, and this is inseparable from nine types of diagrams. drawing is done after watching the video. When I first started to draw a picture, my head was broken, I don't know where to start, so I learned the relationship between the nine images and the four types of graphs again before drawing the picture. I finally got a bit of an idea, this begins to draw. The nine types of UML diagrams include: use case diagram, object diagram, class diagram, component diagram, deployment diagram, state diagram, sequence diagram, activity diagram, and collaboration diagram. The four relationships and nine types of diagrams are the top priorities in UML learning. The most important thing in these nine types of diagrams is the use case diagram, class diagram, and sequence diagram, which can be digested after repeated learning.

I. Concepts

In these nine types of charts, they can be divided into static and dynamic graphs. Static graphs include class graphs, object graphs, use case graphs, component graphs, and deployment diagrams. dynamic graphs include status diagrams, sequence diagram, activity diagram, and collaboration diagram.

1. use case diagram)

It defines the functional requirements of the system. It looks at the system functions from outside the system and does not describe the specific implementation of the functions in the system.

2. Class digraphs)

A description of the static structure used to define the relationship between classes in the system.

3. object diagrams)

Indicates the object instance of the class. It is usually used to show a complex class chart. It reflects the real instance and the relationship between them to help you understand the class.

4. Status chart (statechart diagrams)

Supplementary description of the thing described by the class, the possible states of all objects of the class, and the things that cause state changes.

5. Sequence Diagram (sequence diagrams)

It is also called the sequence diagram, which emphasizes the interaction diagram of the message time sequence, and describes the messages whose classes interact with each other to complete the expected behavior.

6. collaboration diagrams)

A collaboration diagram only models the relationships between objects that interact with each other and these objects, while ignoring other objects and associations.

7. Activity digraphs)

A continuous activity flow is used to describe the activity status when an operation is executed.

8. Component diagram (Component diagrams)

It is mainly used to describe the dependencies between various software components.

9. Deployment diagram (deployment diagrams)

Displays the physical architecture of software and hardware in the system. From the deployment diagram, you can understand the physical relationship between software and hardware components and the component distribution of processing nodes.

II. Application phase of nine types of Graphs

Requirement stage: use case diagram to describe the requirement

Analysis phase:Class diagram description static structure

Design Phase: Application of class charts and package charts to interfaces
Implementation Phase: component diagram and deployment Diagram

Iii. pkcompetition

1. Timeline and collaboration Diagram

Similarities:

(1) The sequence chart and co-drawing belongInteraction DiagramThey represent the interaction between objects,Describes an interaction, which consists of a group of objects and their relationships, and also includes messages transmitted between objects,

(2) Time Sequence diagram and cooperative plot are equivalent.

(3) Both of them come from the same information of the UML meta-model, so their semantics is equivalent. They can be converted from one form of graph to another form of graph, without losing any information.

Differences:

The collaboration diagram emphasizes space,However, the time sequence must be obtained from the serial number.

The time sequence diagram emphasizes the time.But there is no explicit expression of the relationship between objects..

2. Status chart and activity diagram

Similarities:They all belong to behavior graphs, which describe the dynamic behavior of objects.

Differences:

(1) different description objects:
Status chart: Describes the transition between object states. It mainly shows the State of the object.
Activity diagram: Describes the control flow from activity to activity. It mainly represents system actions.
(2) Use Cases are different:
Status chart: Describes the behavior changes of an object during its life cycle.
Activity diagram: describes the process changes.

3. Object diagram and class diagram

Similarities: an object chart is an instance of a class chart and uses almost the same ID as a class chart.

Difference: the object graph shows multiple object instances of the class, rather than the class of the instance. Because the object has a lifecycle, the object graph can only exist in a certain period of time in the system.

4. Activity diagram and use case diagram

The activity diagram is a refinement of the use case diagram.

5. status chart and class chart

A status chart is a supplement to a class chart and helps developers improve a class.

Iv. Summary

The nine types of UML diagrams focus on practice. They can only deepen their understanding of UML through repeated learning. Now, they are only a preliminary study of UML, and their understanding is not so deep. What is wrong, thank you!

Nine types of UML diagrams