(1) The
domain model (domain model) is a visual representation of the actual objects in the conceptual class or problem domain, also known as:
Conceptual models conceptual models
domain object models domain object models
analysis object models
(2) domain models describe real-world classes and their relationships The main content of the
domain model is to capture the information content of the domain
All the class names in the class diagram Vocabulary from the problem domain
(3) Class diagram is a static diagram that has several classes associated together and reflects the structure of the system or subsystem.
The modeling of the class diagram runs through the analysis and design stages of the project. It usually starts with the class that the business partners can understand, and eventually becomes the class that the development team can fully understand.
(4) The class diagram consists of the following elements:
class (class ) ): is an abstract form of a collection of objects with common structural characteristics, behavioral characteristics, relationships and semantics.
Association: It represents the relationship between classes
(5) Identification method (the domain model is established based on the use case model)
1. Use the concept classification list to find the concept
2. Identify the concept class according to the noun phrase
(6) ) Principles of establishing associations
(1) Most of the time domain model creation should be used to identify conceptual classes, not associations.
(2) Declare meaningful connections between concepts from a purely analytical point of view, without considering how to implement the associations.
(3) Associations obtained during the analysis phase may be found to be useless at the design phase.
(7) Establish the association between classes (six kinds of relationships can be established between classes):
(1) Dependency relationship:
It means that the elements of one class use another class. Dependencies refer to the dependencies between two or more classes, such as the plant class depends on the soil class.
Dependencies can be further subdivided into 5 types, namely Binding Dependencies, Realization Dependencies, Usage Dependencies, Abstraction Dependencies, and Permission Dependencies.
The dependency relationship is represented by a dotted arrow, and the arrow points to the direction of dependency
(2) Generalization relationship
Simply speaking, it is the inheritance relationship between classes. In UML, the generalization relationship is represented by a hollow triangle + a solid line, and the arrow points to the parent class.
(3) Association (Association) relationship The
association relationship is a mutual influence relationship between classes, and the direction of influence is the direction of the association. In UML class diagrams, compositional relationships are represented by solid arrows.
(4) Aggregation (Aggregation)
Aggregation is a special case of the association relationship, which reflects the relationship between the whole and the part and the possession, that is, the relationship of has-a, such as (family and children, company and employees).
In the UML class diagram, the aggregation relationship is represented by a hollow diamond + solid arrow, and the arrow points to the aggregated class.
(5) Composition
The composition is also a special case of the association relationship. It embodies a contains-a relationship, which is stronger than aggregation, also known as strong aggregation; it also reflects the relationship between the whole and the part. The relationship between the whole and the part is inseparable, such as (human and brain, bird and wings, frog and legs).
In the UML class diagram, the combination relationship is represented by a solid diamond + solid arrow, and the arrow points to the combined class.
(6) Realization Interfaces can also have inheritance relationships and dependencies similar to those between classes, but there is also a realization relationship (Realization) between interfaces and classes. In this relationship, classes implement The operation in the class implements the operation declared in the interface
(8) Simple class diagram example
Reference :
http://www.cnblogs.com/silent2012/archive/2011/09/07/2169946.html
http ://www.cnblogs.com/liuzhang/archive/2013/03/17/2964427.html