Java 外觀模式

 Java設計模式 - 外觀模式

外觀模式隱藏了系統(tǒng)的復雜性。

它為客戶端提供了一個簡單的接口，客戶端使用接口與系統(tǒng)交互。

外觀模式是結構型模式。

例子

class ShapeFacade {
  interface Shape {
    void draw();
  }
  class Rectangle implements Shape {
    @Override
    public void draw() {
      System.out.println("Rectangle::draw()");
    }
  }
  class Square implements Shape {
    @Override
    public void draw() {
      System.out.println("Square::draw()");
    }
  }
  class Circle implements Shape {
    @Override
    public void draw() {
      System.out.println("Circle::draw()");
    }
  }
  private Shape circle = new Circle();
  private Shape rectangle = new Rectangle();
  private Shape square = new Square();

  public ShapeFacade() {
  }
  public void drawCircle() {
    circle.draw();
  }
  public void drawRectangle() {
    rectangle.draw();
  }
  public void drawSquare() {
    square.draw();
  }
}
public class Main {
  public static void main(String[] args) {
    ShapeFacade shapeFacade = new ShapeFacade();
    shapeFacade.drawCircle();
    shapeFacade.drawRectangle();
    shapeFacade.drawSquare();
  }
}

上面的代碼生成以下結果。