Façade Pattern

Façade Pattern에 대해 설명하는 페이지입니다.

Posted Oct 18, 2023

By HyunJinNo

Tags

Design Pattern, Java

1. Introduction

• Purpose
  • Supplies a single interface to a set of interfaces within a system.
• Use When
  • A simple interface is needed to provide access to a complex system.
  • There are many dependencies between system implementations and clients.
  • Systems and subsystems should be layered.
• Characteristics
  • Provide a unified interface to a set of interfaces in a subsystem. It defines a higher-level interface that makes a subsystem easier to use.
  • Does not prevent sophisticated clients from accessing the underlying classes.
  • It doesn't add any functionality. It just simplifies interfaces.
• Benefits
  • Hides the implementations of the subsystem from clients.
    • makes the subsystem easier to use
  • Promotes weak coupling between the subsystem and its clients
    • allows changing the classes comprising the subsystem without affecting the clients

2. How to Use (Example)

• A set of interfaces

  java

  1public class Class1 {
  2    public void doSomething() {
  3        System.out.print("Hello, ");
  4    }
  5}
  6public class Class2 {
  7    public void doSomething() {
  8        System.out.print("World!");
  9    }
  10}

• Façade

  java

  1public class MyClass {
  2    public void doSomething() {
  3        Class1 c1 = new Class1();
  4        Class2 c2 = new Class2();
  5        c1.doSomething();
  6        c2.doSomething();
  7    }
  8}