WINDEV Concepts

Part 4: Advanced concept 123 • Use case : describes a sequence of actions performed by the application. For example, place an order, enter an invoice, create a new customer entry, etc. A use case describes the actions performed by an application but it does not specify how the application performs these actions. • Relationship : describes the behavior of an actor with a use case. There are three types of relationships: • Association : Structural relationship between two linked elements. • Dependency : Indicates that one element uses or depends on another element. For example, a bank customer may get cash from an ATM. In this case, the Get Cash action depends on the Customer. To withdraw money, the Customer must enter a PIN number. In this case, the Get Cash action depends on the Password. • Generalization : Relationship in which elements are organized based on a hierarchy. For example: • the Customer actor can be of two types: Individual customer or Company customer . • there are two ways to verify the user’s identity: a password or a fingerprint. • Package : divides and organizes the diagram representation (in the same way that directories organize files). Each package can contain actors and use cases. 2.3 Object diagram An object diagram represents a set of objects and how they relate to each other at a certain moment in time. An object diagram is used to show a context (before or after an interaction between objects, for example). For example, the diagram below presents a section of the general structure of motorcycles: An object diagram includes the following elements: • object : represents a class instance. Remark: If a class diagram is opened, you can create an object from a class in this diagram (Drag and drop it from the "UML analysis" pane). • composite object : visually represents an object made of other objects. For example: a window that contains scrollbars, buttons, etc. • link : represents the relationship between different objects. 2.4 Component diagram A component diagram describes the physical and static architecture of a software application. For example: source files, libraries, executables, etc. For example, the diagram below presents the steps of a program that allows users to log in in text mode in Unix.