Class diagrams are a type of structure diagram in UML which clearly illustrates the structure and class descriptions, attributes, methods, and relationships of each object. It is static, in the sense that class diagrams do not explain what happens when the classes are related, but rather explain what relationships occur.


This class diagram is suitable if implemented in projects that use object-oriented concepts because the description of the class diagram is quite easy to use. The model design of this class diagram itself is divided into two parts. The first part is the description of the database. The second part is part of the MVC module, which has interface classes, control classes, and entity classes.


This class diagram has several functions, its main function is to describe the structure of a system. Following are the other functions:

- Shows the structure of a system clearly.
- Increase understanding of the general description or scheme of a program.
- Can be used for business analysis and used to create system models from the business side.
- Can provide an overview of the system or software and the relationships contained therein.


Using class diagrams provides many advantages to the software development process and in business. The following are the advantages of class diagrams:

- Class diagrams serve to explain a data model for a program, both simple and complex data models.
- Gives an overview of the application scheme clearly and better.
- Help you to convey the requirements of a system.


Class diagrams have three constituent components. Following are the components:

Top component
This component contains the class name. Each class must have a different name, another name for this name is a simple name.

Middle component
This component contains the attributes of the class, this component is used to describe the quality of a class. This attribute can be written in more detail, by entering the value type.

bottom component
This component includes operations that are displayed in list form. This operation can describe how a class can interact with data.


After we know the explanation of class diagrams, now we will discuss the relationships between classes. There are three relationships in the class diagram. The following is an explanation:

Association
First there are associations. Association can be interpreted as a relationship between two classes that are static. Usually associations describe classes that have additional attributes like other classes.

Aggregation
Aggregation is a relationship between two classes where one class is part of another class, but these two classes can stand separately.

Inheritance
Inheritance, also known as generalization in class diagrams, is the ability to inherit all attributes and methods from the original class (superclass) to another class (subclass).


The above material was delivered by a presenter from Indonesia in an international visiting lecturer held by STEKOM University in collaboration with Universities from Ukraine. The title of the presentation is "Engineering in the Software Development Model". The name of the presenter is Migunani Hudayatullah, S.Kom., M.Kom. Mr. Migunanani is an active lecturer and head of the Information Systems study program at STEKOM University.


This international webinar activity is part of the implementation of STEKOM University's commitment to increase various international activities. This was done in order to realize the vision to become an international-class university. Various international activities carried out by STEKOM University continue from year to year. There are international activities that are sustainable and there are also some international activities that are not sustainable. All types of international activities are accommodated and regulated by the International department of STEKOM University.