What are the differences between a static class and a singleton class?
- A singleton class can be extended, while a static class cannot be extended
- A singleton class can have multiple instances, while a static class can only have one instance
- A static class can be extended, while a singleton class cannot be extended
- A static class can have multiple instances, while a singleton class can only have one instance
A static class can have multiple instances, while a singleton class can only have one instance. A static class is a class that is declared as static and can only access static variables and methods. A singleton class is a class that ensures that only one instance of the class exists in the JVM.
What's the difference between the Dependency Injection and Service Locator patterns?
- The Dependency Injection pattern involves a central registry that provides objects when requested, while the Service Locator pattern involves passing objects as dependencies to the objects that require them.
- The Dependency Injection pattern involves creating and configuring objects, while the Service Locator pattern involves finding and returning objects.
- The Dependency Injection pattern involves finding and returning objects, while the Service Locator pattern involves creating and configuring objects.
- The Dependency Injection pattern involves passing objects as dependencies to the objects that require them, while the Service Locator pattern involves a central registry that provides objects when requested.
The Dependency Injection pattern involves passing objects as dependencies to the objects that require them, while the Service Locator pattern involves a central registry that provides objects when requested. The Dependency Injection pattern provides objects to its client as they are needed, while the Service Locator pattern allows objects to request objects they need from a centralized registry.
What is the difference between Façade and Mediator?
- Façade and Mediator are the same thing.
- Façade and Mediator have no relationship to each other.
- Façade is a pattern for communication between components of a system, while Mediator is a simplified interface to a complex system. Façade is a two-way communication pattern, while Mediator is a one-way communication pattern.
- Façade is a simplified interface to a complex system, while Mediator is a pattern for communication between components of a system. Façade is a one-way communication pattern, while Mediator is a two-way communication pattern.
The Façade pattern provides a simplified interface to a complex system, while the Mediator pattern provides a way for components of a system to communicate with each other in a loosely coupled manner. Façade is a one-way communication pattern, while Mediator is a two-way communication pattern.
What is the purpose of the Facade pattern?
- To allow multiple objects to communicate with each other
- To create a reusable object-oriented design
- To provide a common interface for a group of related classes
- To provide a simplified interface to a complex system, hiding the complexity of the system behind a single interface and making it easier to use
The Facade pattern provides a simplified interface to a complex system, hiding the complexity of the system behind a single interface and making it easier to use
What is relationship between Repository and Unit of Work?
- The Repository and Unit of Work patterns are interchangeable, as they both provide similar functionality and can be used interchangeably in a project.
- The Repository and Unit of Work patterns are not related, as they are completely separate design patterns with different purposes.
- The Repository and Unit of Work patterns are related, as the Unit of Work is responsible for managing the persistence of data changes, while the Repository provides an abstraction over the data access layer. The Repository can use the Unit of Work to persist changes to the data.
- The Repository and Unit of Work patterns are the same, as they are both used to manage the persistence of data changes.
The Repository and Unit of Work patterns are related, as the Unit of Work is responsible for managing the persistence of data changes, while the Repository provides an abstraction over the data access layer. The Repository can use the Unit of Work to persist changes to the data.
What is Design Patterns and why anyone should use them?
- A collection of best practices for software development that are specific to a certain programming language or framework.
- A pre-written solution to common software problems that can be adapted to fit the specific needs of a project. Design patterns provide a common vocabulary and shared understanding among team members, allowing for more efficient and maintainable code.
- A set of coding conventions that must be followed when developing software to ensure consistency and readability.
- A set of guidelines for designing user interfaces in a way that is aesthetically pleasing and easy to use.
Design Patterns are reusable solutions to common problems that arise in software development. They provide a standardized way of approaching these problems, which can improve the efficiency, maintainability, and understandability of the code.
What is Observer pattern?
- A design pattern in which an object, called the composite, is composed of one-to-many other objects, in a tree-like structure, allowing the client to interact with individual objects and compositions of objects uniformly
- A design pattern in which an object, called the decorator, adds or overrides behavior of an existing object, dynamically
- A design pattern in which an object, called the proxy, acts as an intermediary between a client and a target object, forwarding requests from the client to the target object and vice versa
- A design pattern in which an object, called the subject, maintains a list of its dependents and notifies them automatically of any changes to its state
The Observer pattern is a design pattern in which an object, called the subject, maintains a list of its dependents and notifies them automatically of any changes to its state. The Observer pattern is used to implement a publish/subscribe mechanism, allowing the subject to be decoupled from its dependents, and allowing multiple dependents to be notified of changes to the subject's state. The Observer pattern is used to implement event-driven systems.
What is the difference between the State and Strategy patterns?
- None of the above
- The State and Strategy patterns are the same
- The State pattern allows an object to alter its behavior when its internal state changes, while the Strategy pattern allows an object to change its behavior based on the context it is in
- The State pattern allows an object to change its behavior based on the context it is in, while the Strategy pattern allows an object to alter its behavior when its internal state changes
The State pattern allows an object to alter its behavior when its internal state changes, while the Strategy pattern allows an object to change its behavior based on the context it is in
What is the Visitor pattern?
- A behavioral design pattern that lets you pass requests along a dynamic chain of receivers until one of them handles it.
- A behavioral design pattern that separates an algorithm from an object structure on which it operates. The pattern allows you to define a new operation without changing the classes of the objects on which it operates.
- A creational design pattern that uses factory methods to deal with the problem of creating objects without specifying the exact class of object that will be created.
- A structural design pattern that allows you to compose objects into tree structures to represent part-whole hierarchies.
A behavioral design pattern that separates an algorithm from an object structure on which it operates. The pattern allows you to define a new operation without changing the classes of the objects on which it operates.
What is Inversion of Control?
- A mechanism for managing dependencies between software components, such as libraries or services, that are required to run an application.
- A method of testing in which dependencies are replaced with mock objects to isolate the test subject from the rest of the system.
- A software design principle in which the flow of control of a system is inverted compared to the traditional approach. Instead of the system calling a component to perform a task, the component is notified when a task is ready and performs it. This leads to a more flexible and decoupled system, allowing for easier maintenance and testing.
- A technique for structuring software components into a tree-like hierarchy to organize dependencies and reduce coupling between components.
Inversion of Control is a design principle in which the flow of control in a system is inverted. Instead of a system calling components to perform tasks, components are notified when tasks are ready and perform them. This leads to a more flexible and decoupled system, allowing for easier maintenance and testing.