26 Lecture

Q: What are design patterns in software development? a) Detailed implementation guidelines for specific programming languages. b) Reusable solutions to common software design problems. c) Comprehensive project management methodologies. d) Documentation templates for software projects. Solution: b) Reusable solutions to common software design problems. Q: Which of the following is a benefit of using design patterns? a) Increased software complexity. b) Reduced code flexibility. c) Improved code maintainability. d) Limited code reusability. Solution: c) Improved code maintainability. Q: Design patterns are intended to be: a) Specific to individual programming languages. b) Adapted to each software project independently. c) Reusable across various software projects. d) Only used in small-scale applications. Solution: c) Reusable across various software projects. Q: The Singleton pattern ensures that a class has: a) Multiple instances with shared data. b) Multiple instances with separate data. c) Only one instance throughout the application. d) Multiple instances with limited access. Solution: c) Only one instance throughout the application. Q: Which design pattern promotes loose coupling between objects? a) Adapter pattern. b) Observer pattern. c) Facade pattern. d) Singleton pattern. Solution: b) Observer pattern. Q: In the Factory Method pattern, the responsibility of object creation is: a) Assigned to the client code. b) Delegated to a factory class. c) Shared between multiple classes. d) Ignored, as objects are created implicitly. Solution: b) Delegated to a factory class. Q: The Strategy pattern enables: a) Objects to communicate with each other. b) Dynamically changing algorithms or behaviors. c) Objects to share their data with others. d) Objects to hide their internal structure. Solution: b) Dynamically changing algorithms or behaviors. Q: Which design pattern provides a simple interface to a complex subsystem? a) Singleton pattern. b) Facade pattern. c) Factory Method pattern. d) Adapter pattern. Solution: b) Facade pattern. Q: The Chain of Responsibility pattern is used to: a) Establish relationships between classes in an inheritance hierarchy. b) Create a chain of interconnected objects to process a request. c) Ensure that only one instance of a class exists throughout the application. d) Simplify the creation of objects in complex systems. Solution: b) Create a chain of interconnected objects to process a request. Q: The Decorator pattern allows: a) Adding new functionalities to objects dynamically. b) Sharing data between multiple objects. c) Preventing multiple instances of a class. d) Restricting access to certain classes. Solution: a) Adding new functionalities to objects dynamically.

Q: What are design patterns in software development? A: Design patterns are reusable solutions to common software design problems that provide proven approaches to address specific challenges. Q: How do design patterns contribute to software development? A: Design patterns improve code maintainability, flexibility, and scalability by promoting best practices and standard solutions to common problems. Q: Give an example of a creational design pattern. A: An example of a creational design pattern is the Singleton pattern, which ensures a class has only one instance throughout the application. Q: How does the Observer pattern promote loose coupling between objects? A: The Observer pattern allows subjects (observed objects) to notify multiple observers (listeners) without knowing their specifics, achieving loose coupling. Q: What is the purpose of the Factory Method pattern? A: The Factory Method pattern delegates the responsibility of object creation to a factory class, allowing clients to create objects without specifying the exact class. Q: How does the Strategy pattern enable dynamically changing behaviors? A: The Strategy pattern encapsulates interchangeable algorithms, allowing clients to switch between different strategies at runtime, thus enabling dynamic behavior changes. Q: Provide an example where the Facade pattern simplifies a complex subsystem. A: In a multimedia player, the Facade pattern provides a simple interface to interact with various subsystems like audio, video, and playlist management. Q: How does the Chain of Responsibility pattern work? A: The Chain of Responsibility pattern creates a chain of interconnected handlers, where each handler processes a request and passes it to the next handler until it's handled or reaches the end of the chain. Q: Explain the role of the Decorator pattern in software design. A: The Decorator pattern allows adding new functionalities to objects dynamically without modifying their structure, enhancing flexibility and promoting code reuse. Q: What advantage does using design patterns offer to software developers? A: Design patterns simplify the design process, enhance code readability, and promote best practices, making it easier for developers to build robust and maintainable software.