UML Use Case Diagrams: A Restaurant System Case Study

Business use-case diagrams are used to model and illustrate interactions between business actors and processes within businesses. They are used in software development to capture a system's requirements, which is essential in the early stage of development. A use-case diagram illustrates the behavior of systems, helping to capture the working requirements of those systems. Actors can be people, organizations, or external or internal systems that interact with the business, while use cases are specific functionalities or services that the business provides to the actors and other use cases. The restaurant customer service system is an example of a business use-case diagram, which represents one functionality of a restaurant organization. It involves external actors such as dine-in customers and takeaway customers, and internal actors such as servers, bussers, hosts, service managers, and cooks. Use cases include placing an order, making a payment, and preparing food, and relationships within the system include associations, includes, and extends. Business use cases can be divided into base cases and additional cases, and can also be categorized into business processes, supporting activities, and management activities. Actors can be categorized as external or internal, and relationships between actors and use cases can be defined as association, include, extend, or generalization relationships. UML use-case diagrams have several advantages in software development, including providing a user-centric approach, being easy to recognize and understand, and facilitating tracing of requirements. However, they also have limitations, such as not capturing non-functional requirements, not being object-oriented in nature, and not providing a good basis for coding. Overall, business use-case diagrams are a powerful tool for modeling and visually representing interactions between business actors and processes within businesses. They can be used to capture system requirements and provide a user-centric approach to software development.