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Use case diagram for online telephone directory system
Use case diagram for online telephone directory system










In composition, a class is strongly connected to another class that it will stop functioning without it. The aggregation has another special type, called composition. For example, if an employee does not come, the organization will remain there. In aggregation, 2 classes have a whole-part relationship. If 100 people work at an organization, then the attribute has multiplied 100 times. The multiplicity factor in association represents how many times an attribute is multiplied. The association between a student and school is “studies”. Checking, Savings, and Credit Accounts are generalized by AccountĪssociation shows a static relationship between two entities. The class diagram allows a subclass to inherit from multiple superclasses but it can’t be used to model interface implementation. Generalizations are often known as Inheritance because it links a subclass to its superclass. There are three main types of relationships here:

use case diagram for online telephone directory system

To create a class diagram, the next step is building relationships. You don’t need to show operations that are similar to attributes because one can already deduce that from the information. They correspond to the methods of a class.

use case diagram for online telephone directory system

Operations are processes that a class knows to carry out.

use case diagram for online telephone directory system

Attributes must be meaningful and are usually used with the visibility factor that describes the accessibility of an attribute. You can simply add new attributes or derive new attributes from already listed attributes. Moreover, an abstract class should be written in italics.Īttributes are written in the middle compartment and list down all the properties of the object being modeled. It should be written in bold in the top compartment and start with a capital letter. The class name is important for graphical representation. The rectangle is divided into three compartments with the topmost being Class Name, then Attributes in the middle, and Operations in the bottom. There are three major parts of a class diagram as shown in the image below:Ī single rectangle is used to represent the class as shown above.












Use case diagram for online telephone directory system