In the previous discussion on the Abstract Factory pattern, we encountered a limitation regarding the flexibility of object creation. This article presents a solution using Component Object Model (COM) technology and explores how the Factory Pattern is utilized within it. The fundamental reason the...
Factory Pattern is one of the most commonly used creational design patterns in software development, particularly in Java and C++. It provides a standardized way to create objects while hiding the underlying instantiation logic from client code, and uses a shared interface to reference the newly cre...
What is a Protocol? A protocol in Objective-C serves a similar purpose to interfaces in Java. It defines a contract of methods that a class must implement, without providing any implementation details or member variables. Key Characteristics of Protocols Protocols exist solely to declare collections...
The Adapter pattern serves as a bridge between incompatible interfaces, enabling seamless integration of existing componants into new systems without altering their original structure. This is particular useful in scenarios where third-party services—such as Alipay or WeChat Pay—must be incorporated...
1. Single Responsibility Principle (SRP)The Single Responsibility Principle states that a class should have only one reason to change. In practical terms, this means a module should be responsible for a single functional area or logic within the application. This principle serves as a foundation for...
The Simple Factory pattern centralizes object instantiation behind a unified interface, adhering strictly to the Dependency Inversion Principle. High-level modules interact exclusively with abstractions rather than concrete implementations, decoupling client logic from construction details. 1. Abstr...
The Singleton pattern is a creational design pattern intended to ensure that a class has exactly one instance while providing a global point of access to that instance. This pattern is particularly valuable when coordinating actions across a system or managing shared resources where multiple instanc...
SPI (Service Provider Interface) is a standard Java mechanism for enabling service discovery and dynamic component loading. It facilitates loose coupling by separating service interface definitions from their concrete implementations, allowing runtime loading of providers without modifying the core...
The Singleton pattern ensures a class has only one instance and provides a global point of access to it. Instead of relying on global variables—which can be instantiated multiple times—the class itself controls the creation and storage of its sole instance, guaranteeing uniqueness. Class Structure T...
Consider a document editing application where users compose text but lack the ability to reverse accidental deletions. Without a mechansim to capture prior conditions, each modification permanently alters the working state. public class Draft { private StringBuilder manuscript = new StringBuilder();...