Static & Private Class Fields

What pattern is implemented using private fields?

class Database {
  static #instance;
  #connection;
  
  constructor() {
    if (Database.#instance) {
      return Database.#instance;
    }
    this.#connection = this.#connect();
    Database.#instance = this;
  }
  
  #connect() {
    // Connection logic
  }
}

Factory pattern
Observer pattern
Singleton pattern
This implements the Singleton pattern using private fields: 1) Private static #instance ensures single instance control, 2) Private #connection field protects the connection state, 3) Private #connect method encapsulates connection logic, 4) Instance check and storage are fully encapsulated, 5) Cannot be circumvented from outside the class, 6) More robust than traditional JavaScript singleton implementations.
Builder pattern

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