UML Use Case Diagram? Basic Use Case Diagram Symbols and Notations

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1 This file will be helpful during viva exam. You should have all the knowledge about the diagrams which you have included in your presentation. You should know all the symbols, relationships. You must prepare one of your favorite subjects. You should know about your software/product and coding. Also how specific activity or function is working. Best of luck: No need to be tense. There will be friendly environment. UML Use Case Diagram? Use case diagrams model the functionality of a system using actors and use cases. Use cases are services or functions provided by the system to its users. Basic Use Case Diagram Symbols and Notations System Draw your system's boundaries using a rectangle that contains use cases. Place actors outside the system's boundaries.

2 Use Case Draw use cases using ovals. Label with ovals with verbs that represent the system's functions. Actors Actors are the users of a system. When one system is the actor of another system, label the actor system with the actor stereotype. Relationships Illustrate relationships between an actor and a use case with a simple line. For relationships among use cases, use arrows labeled either "uses" or "extends." A "uses" relationship indicates that one use case is needed by another in order to perform a task. An "extends" relationship indicates alternative options under a certain use case.

3 Data Flow Diagram (DFD) Data flow diagram (DFD) represents the flows of data between different processes in a business. It is a graphical technique that depicts information flow and the transforms that are applied as data move form input to output. Context Diagrams A context diagram is a top level (also known as Level 0) data flow diagram. It only contains one process node (process 0) that generalizes the function of the entire system in relationship to external entities. Level 1 data flow diagram is the refinement of the context (0-level) data flow diagram. All the external entities are the same; however, the process is further elaborated by the other processes The level of detail. The Level 1 shows the whole system. Level 2 focus more closely on one particular process in the level 1, and the level 3 focuses on a single process from a level 2.

4 Entity Relationship Diagrams? Entity Relationship Diagrams (ERDs) illustrate the logical structure of databases. Entity relationship model (ER model) in software engineering is an abstract way to describe a database.

5 Examples of Entity Relationship Diagram

6 An entity relationship diagram example, showing a simple database for the business order process. Cardinality and Modality Cardinality and Modality work together to define the relationship. Cardinality indicates the maximum number of times an instance in one entity can be associated with instances in the related entity. Modality indicates the minimum number of times an instance in one entity can be associated with an instance in the related entity. Thus, Modality is also called participation because it denotes whether or not an instance of an entity MUST participate in the relationship. Cardinality and Modality are both shown on the relationship line by symbols. We will go over each of the symbols and how to interpret them. Cardinality Cardinality indicates the maximum number of times an instance of one entity can be associated with instances in the related entity. Cardinality can have the values of one or many, no more

7 detail than that. It is either one or more than one. On the relationship line, the cardinality is the closest to the entity box. The cardinality symbol in the diagram on the slide is in the red circle. Cardinality is indicated at BOTH ends of the relationship line, so there is a left to right cardinality and a right to left cardinality. Modality Modality indicates the minimum number of times an instance in one entity can be associated with an instance in the related entity. Modality can have the values of zero or one, two or three are not allowed. The modality symbol is located next to the cardinality symbol, on the inside, i.e., NOT next to the entity box. A modality of one is denoted by a straight vertical line and a modality of zero is denoted by a circle. Like cardinality, modality is indicated at both ends of the relationship. Reading Modality and Cardinality Activity diagram Activity diagrams are graphical representations of workflows of stepwise activities and actions with support for choice, iteration and concurrency. Activity diagram is basically a flow chart to represent the flow form one activity to another activity. The activity can be described as an operation of the system.

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9 What is a UML Sequence Diagram? Sequence diagrams describe interactions among classes in terms of an exchange of messages over time. Basic Sequence Diagram Symbols and Notations Class roles

10 Class roles describe the way an object will behave in context. Use the UML object symbol to illustrate class roles, but don't list object attributes. Activation Activation boxes represent the time an object needs to complete a task. Messages Messages are arrows that represent communication between objects. Use half-arrowed lines to represent asynchronous messages. Asynchronous messages are sent from an object that will not wait for a response from the receiver before continuing its tasks.

11 Various message types for Sequence and Collaboration diagrams Lifelines Lifelines are vertical dashed lines that indicate the object's presence over time. Destroying Objects Objects can be terminated early using an arrow labeled "<< destroy >>" that points to an X.

12 Loops A repetition or loop within a sequence diagram is depicted as a rectangle. Place the condition for exiting the loop at the bottom left corner in square brackets [ ]. KEYS Primary Key, Secondary Key, Candidate Key, Unoque Key, Foreign Key Class Diagram: Class diagrams are used to represents real life objects in our design by capturing its data methods and relationships of these methods with each other. These classes are basic building blocks of our object oriented system. Class diagrams are represented with white boxes which consist of three parts. Each of these parts has unique characteristics.

13 The details of these parts are as follow. 1. The upper part contains the name of the class for our object oriented design. 2. The next part contains the attributes of the class. 3. The third part contains the methods and operations on the class. Database design: In our daily life every object has some data associated with it. This data can be managed through data base design. Data large data can be represented by this data base design. Data base design can be represented in the form of physical, conceptual and logical. Interface Diagram: Interface diagram are used to represents Graphical User Interface (GUI) of our system. GUI consists of Buttons, text fields and check boxes etc. Deployment Diagram: Deployment Diagram represents the physical view of the system. Deployment diagram shows the relationship between pieces of software execution and hardware that will execute this piece. The Deployment Diagram also shows the relationship among different devices. For example system topology, installation of the devices and communication of these devices. Test Cases: A test case in software engineering is a set of circumstances or variables under which a tester will determine whether a software system is working according to implementation and giving expected results or not. It may take many test cases to determine that a software system is functioning correctly. When test case are documented then referred to as test scripts.