Figure1 Use Case diagram for Online reservation system. At Lucidchart, we provide free examples of sequence diagrams in UML for your convenience.
View image at full size Importance of understanding the basics It is more important than ever in UML 2 to understand the basics of the class diagram. This is because the class diagram provides the basic building blocks for all other structure diagrams, such as the component or object diagrams just to name a few.
Beyond the basics At this point, I have covered the basics of the class diagram, but do not stop reading yet!
In the following sections, I will address more important aspects of the class diagram that you can put to good use. These include interfaces, the three remaining types of associations, visibility, and other additions in the UML 2 specification.
Interfaces Earlier in this article, I suggested that you think of classifiers simply as classes. In fact, a classifier is a more general concept, which includes data types and interfaces. A complete discussion of when and how to use data types and interfaces effectively in a system's structure diagrams is beyond the scope of this article.
So why do I mention data types and interfaces here? There are times when you might want to model these classifier types on a structure diagram, and it is important to use the proper notation in doing so, or at least be aware of these classifier types.
Drawing these classifiers incorrectly will likely confuse readers of your structure diagram, and the ensuing system will probably not meet requirements. A class and an interface differ: A class can have an actual instance of its type, whereas an interface must have at least one class to implement it.
In UML 2, an interface is considered to be a specialization of a class modeling element. Example of a class diagram in which the Professor and Student classes implement the Person interface View image at full size In the diagram shown in Figure 10, both the Professor and Student classes implement the Person interface and do not inherit from it.
We know this for two reasons: As shown in Figure 10, a dotted line with a closed, unfilled arrow means realization or implementation ; as we saw in Figure 4, a solid arrow line with a closed, unfilled arrow means inheritance.
More associations Above, I discussed bi-directional and uni-directional associations. Now I will address the three remaining types of associations.
Association class In modeling an association, there are times when you need to include another class because it includes valuable information about the relationship. For this you would use an association class that you tie to the primary association.
An association class is represented like a normal class. The difference is that the association line between the primary classes intersects a dotted line connected to the association class. Figure 11 shows an association class for our airline industry example.
Adding the association class MileageCredit View image at full size In the class diagram shown in Figure 11, the association between the Flight class and the FrequentFlyer class results in an association class called MileageCredit.
This means that when an instance of a Flight class is associated with an instance of a FrequentFlyer class, there will also be an instance of a MileageCredit class. Aggregation Aggregation is a special type of association used to model a "whole to its parts" relationship. In basic aggregation relationships, the lifecycle of a part class is independent from the whole class's lifecycle.
For example, we can think of Car as a whole entity and Car Wheel as part of the overall Car. The wheel can be created weeks ahead of time, and it can sit in a warehouse before being placed on a car during assembly.
In this example, the Wheel class's instance clearly lives independently of the Car class's instance. However, there are times when the part class's lifecycle is not independent from that of the whole class — this is called composition aggregation.
Consider, for example, the relationship of a company to its departments.Agile Use Case Tool. Create diagrams easily. Define use cases and requirements. Generate clear, readable specifications. Take the Tour. Use Case Diagrams.
Clarify requirements with use cases, actors, and relationships. CaseComplete is the requirements management tool that business analysts love. Organizations around the world - large and.
A UML Use Case Diagram showing Hospital Management System. You can edit this UML Use Case Diagram using Creately diagramming tool and include in your report/presentation/website. Proposed System The Hospital Management System (HMS) is designed for Any Hospital to replace their existing manual, paper based system.
The new system is to control the following information; patient information, room availability, staff and operating room schedules, and patient invoices.
Below is the case study of it for the construction of different UML diagrams CASE STUDY: Hospital Management System Hospital management system helps in registering information about patients and handles patient’s query.
UML 2 class diagrams are the mainstay of object-oriented analysis and design. UML 2 class diagrams show the classes of the system, their interrelationships (including inheritance, aggregation, and association), and the operations and attributes of the classes.
A full case study in UML HOSPITAL MANAGEMENT SYSTEM: Patient Admit / Registration Uing Visual Paradigm Community Edition for Illusration Case Study Description: The hospital has several specialized departments like Cardiology, Gynecologic, Orthope.