结构型模式-装饰器模式

Posted 2021-01-26 liunianfeiyu

　　对原有对象进行修饰，如有一个篮子，现在对篮子进行修饰，放入苹果，香蕉，橙子

package constructional.pattern.decorator;

/* 
 * 创建一个对象的抽象也就是接口 
*/  
public interface Basket {  
    public void show();  
      
}

package constructional.pattern.decorator;

/** 
 *身份：被装饰的对象 
 *一个对接口的实现，这个对象表示要我们将来要修饰的篮子里装内容，如果想修饰篮子的造型，还可以创建其他类实现Basket的接口,比如Shape 
 * 不理解的话可以查看java语言的接口抽象机制 
*/  
public class Original implements Basket{  
    public void show(){  
      System.out.println("The original Basket contains");  
    }  
}

package constructional.pattern.decorator;

/** 
 *身份：装饰器 
 *为原来的类添加新的功能 
*/  
public class AppleDecorator implements Basket{  
    private Basket basket;  
    public AppleDecorator( Basket basket){  
      super();  
      this.basket = basket;  
    }  
      
    public void show(){  
      basket.show();  
      System.out.println("An Apple");  
    }  
      
}

package constructional.pattern.decorator;

/** 
 *身份：装饰器 
*/  
public class BananaDecorator implements Basket{  
    private Basket basket;  
    public BananaDecorator(Basket basket){  
        super();  
        this.basket = basket;  
    }  
      
    public void show(){  
        basket.show();  
        System.out.println("A Banana");  
    }  
      
}

package constructional.pattern.decorator;

/** 
 *身份：装饰器 
*/  
public class OrangeDecorator implements Basket{  
    private Basket basket;  
    public OrangeDecorator(Basket basket){  
        super();  
        this.basket = basket;  
    }  
      
    public void show(){  
        basket.show();  
        System.out.println("An Oranage");  
    }  
      
}

　　测试代码如下：

package constructional.pattern.decorator;
/* 
 * 设计模式：装饰器模式 
 * java 简单的演示 
*/  
  
/** 
 * 
 * @author octobershiner 
 * 2011 7 25 
 * SE.HIT 
*/  
public class DecoratorPattern {  
  
    /** 
     * @param args the command line arguments 
*/  
    public static void main(String[] args) {  
        // TODO code application logic here  
        Basket basket = new Original();  
        //一个装饰的过程  
        Basket myBasket =new AppleDecorator(new BananaDecorator(new OrangeDecorator(basket)));   
        myBasket.show();  
    }  
}

　　运行结果：