In the expression of class diagram, we must pay business email list attention to the difference between arrows.
a) Connected by a straight line, representing the relationship between the two classes, when the specific relationship is uncertain, use a straight line to link first; the numbers at both ends of the straight line represent the corresponding quantitative relationship, as follows:
Representing 1 G can have 0-3 M, for example, a group can have 0-3 members in addition to the leader.
b) Navigation relationship
It means that A can navigate to B. Generally speaking, A can find B. For example, participating users can be found in the group list.
② Aggregation relationship, that is, weak inclusion relationship
Representing a department can be composed of multiple employees. If the department disappears, the employees can continue to exist.
③ Combination relationship, that is, strong inclusion relationship
Representing a department can be composed of multiple employees. If the department disappears, the employees will also disappear.
④ Generalization relationship
It means that A generalizes to B, A has the characteristics of B, and also has its own unique characteristics, such as banana generalization to fruit.
It means that A depends on B, and for something, A needs the assistance of B to get it done.
3) Steps of class diagram modeling
To identify a class, first note the name of the class;
Identify the main attributes and operations of the class;
Delineate the relationships between classes;
Analyze, abstract, and organize various types.
This picture was found on the Internet, and the use of arrows is not very standardized. Remember to use arrows in class diagram syntax.
2. Component diagram
1) What is a component?
① A component symbol is as follows. The service interface is like a hand and a fist, and the contact memory is: reach out for service, and punch people for service.
② The connection between the two components is as follows:
③ The example is as follows:
3. Deployment diagram
Product managers generally need to figure out:
Where is the server deployed? Where is the database placed?
Internet or LAN?
4. Activity Diagram (Flowchart)
Activity diagrams are more commonly used and don’t tell much about them, but they must be standardized when drawing. For example, each activity is expressed in the form of “active object”. When a swimming lane diagram is used and there is a role swimming lane, the “subject” can be omitted.
2) Drawing steps
What is the business purpose of the process?
What is the role of this process?
Drawing the process under normal circumstances is the backbone of the process, generally a linear process.
Identify roles and activities in the backbone process.
The branch process is gradually increased, and the key process branches are drawn. Some abnormal processes can be simply drawn and explained in words.
Appropriate control of activity granularity.
Optimize the process.
5. State Machine Diagram
A state machine diagram shows a process in terms of how the state of something changes. The expression of "active object" should also be strictly used when describing the triggering behavior.