Master 23 Classic Design Patterns with Real-World Analogies

Factory Method

When courting a girl, ordering chicken wings at McDonald’s or KFC is like a Factory pattern: the client and the factory are separated, and the consumer simply asks for four wings while the restaurant produces them.

Builder Pattern

Having a multilingual love‑phrase machine that says “I love you” in the appropriate language for each girl is analogous to a Builder, separating the product’s internal representation from its construction process.

Abstract Factory

Taking a girl to order a burger and letting her specify the exact type mirrors an Abstract Factory, where the core factory delegates the creation of concrete products to subclasses.

Prototype Pattern

Collecting a stash of cheesy love lines and copying them into a chat whenever needed exemplifies the Prototype pattern, which creates new objects by cloning an existing prototype.

Singleton Pattern

Having six wives all referring to the same husband illustrates a Singleton, ensuring that only one instance of a class exists system‑wide.

Adapter Pattern

A friend who translates between me and a Hong‑Kong girl who speaks Cantonese acts as an Adapter, converting one interface into another so the two can communicate.

Bridge Pattern

Using different greetings for morning, evening, new clothes, or new hairstyles and combining them flexibly demonstrates the Bridge pattern, which decouples abstraction from implementation.

Composite Pattern

Buying multiple gifts for a birthday and treating the collection as a single composite object reflects the Composite pattern, which lets clients treat individual objects and compositions uniformly.

Decorator Pattern

Adding a photo frame and a custom box to a gift to enhance its appearance illustrates the Decorator pattern, which extends an object’s functionality without altering its core.

Facade Pattern

A camera’s auto mode that handles aperture and shutter settings for the user acts as a Facade, providing a simplified high‑level interface to a complex subsystem.

Flyweight Pattern

Storing frequently used phrases on a phone and reusing them with different names demonstrates the Flyweight pattern, which shares common state to reduce memory usage.

Proxy Pattern

Automating replies to repetitive chat greetings via a program that intercepts and responds on my behalf exemplifies the Proxy pattern, which controls access to another object.

Chain of Responsibility

Passing a love note up the rows of a classroom until someone handles it mirrors the Chain of Responsibility, where a request traverses a chain of handlers.

Command Pattern

Using a brother to deliver written instructions (commands) to a girl, and rewarding him for doing so, illustrates the Command pattern, which encapsulates a request as an object.

Interpreter Pattern

Following a scripted set of dating steps like a manual shows the Interpreter pattern, which defines a language grammar and evaluates sentences.

Iterator Pattern

Iterating through a list of purchases (diamond, house, sports car) for a girlfriend demonstrates the Iterator, which provides sequential access to elements without exposing the underlying structure.

Mediator Pattern

Acting as a neutral party to settle bets among four girls playing mahjong exemplifies the Mediator pattern, which centralizes communication between objects.

Memento Pattern

Saving snapshots of conversations with different girls in a memo so they can be reviewed later reflects the Memento pattern, which captures and restores an object’s internal state.

Observer Pattern

Subscribing to a mailing list that automatically forwards new information about girls to all observers illustrates the Observer pattern, which notifies dependents of state changes.

State Pattern

A girl’s behavior changing with her internal state—uninterested, neutral, or enthusiastic—mirrors the State pattern, which alters an object’s behavior when its state changes.

Strategy Pattern

Selecting different dating tactics (movie, snack, beach) for different girls demonstrates the Strategy pattern, which encapsulates interchangeable algorithms.

Template Method Pattern

The fixed sequence of steps in a seduction guide (encounter, break the ice, pursue, kiss, etc.) with customizable sub‑steps exemplifies the Template Method pattern, which defines a skeleton algorithm while allowing subclasses to refine certain steps.

Visitor Pattern

Having a florist and a gift shop act as visitors to customize flowers and cards for each girl shows the Visitor pattern, which separates operations from the object structure they operate on.

Source: zhuanlan.zhihu.com/p/100746724