装饰者模式

今天把java编程思想的IO系统重新温习了一下，对装饰者模式有了更加深刻的理解。下面以我的理解重新构思了程序，直接上code

Human（人类）-我们需要装饰的对象

 1 /**
 2  * 
 3  */
 4 package com.decorate;
 5 
 6 /**
 7  * @author Administrator
 8  *
 9  */
10 public interface Human {
11     
12     /**
13      * 
14 */
15     public void printDescription();
16 }

 

由Human派生出来的两个被装饰类Man（男人）和Woman（女人）

/**
 * 
 */
package com.decorate;

/**
 * @author Administrator
 *
 */
public class Man implements Human {

    /* (non-Javadoc)
     * @see com.decorate.Human#printDescription()
     */
    @Override
    public void printDescription() {
        System.out.println("男人");
    }

}

 

/**
 * 
 */
package com.decorate;

/**
 * @author Administrator
 *
 */
public class Woman implements Human {

    /* (non-Javadoc)
     * @see com.decorate.Human#printDescription()
     */
    @Override
    public void printDescription() {
        System.out.println("女人");
    }

}

 

有了需要装饰的对象，我们开始实现装饰者。首先需要一个所有装饰者基类，即抽象类Decorator，以后定义的所有装饰者都有继承自这个类

/**
 * 
 */
package com.decorate;

/**
 * @author Administrator
 *
 *装饰人的抽象类
 */
public abstract class Decorator implements Human {
    
    /**
     * 被装饰的人
     */
    public Human human;
    
    public Decorator(Human human){
        this.human = human;
    }
    
    /* (non-Javadoc)
     * @see com.decorate.Human#printDescription()
     */
    @Override
    public void printDescription() {
        human.printDescription();
    }

}

然后我们开始进行具体的装饰，比如：你想把这个人装饰成黄皮肤的、长头发的，还是他吃饭、散步....  下面是三个具体的装饰者：

1.长头发

/**
 * 
 */
package com.decorate;

/**
 * @author Administrator
 *
 * 把human变成长头发
 */
public class HairstyleDecorator extends Decorator {

    /**
     * @param human
     */
    public HairstyleDecorator(Human human) {
        super(human);
        // TODO Auto-generated constructor stub
    }
    
    /* (non-Javadoc)
     * @see com.decorate.Decorator#printDescription()
     */
    public void printDescription(){
        System.out.print("长头发-");
        super.printDescription();
    }

}

2.黄皮肤

/**
 * 
 */
package com.decorate;

/**
 * @author Administrator
 * 把human变成黄皮肤
 */
public class YellowskinDecorator extends Decorator {

    /**
     * @param human
     */
    public YellowskinDecorator(Human human) {
        super(human);
        // TODO Auto-generated constructor stub
    }
    
    public void printDescription(){
        System.out.print("黄皮肤-");
        super.printDescription();
    }

}

3.让human散步

/**
 * 
 */
package com.decorate;

/**
 * @author Administrator
 * 使human在散步
 */
public class WalkingDecorator extends Decorator {

    /**
     * @param human
     */
    public WalkingDecorator(Human human) {
        super(human);
        // TODO Auto-generated constructor stub
    }
    
    public void printDescription(){
        super.printDescription();
        System.out.println("-在散步");
    }

}

 

测试类：

/**
 * 
 */
package com.decorate;

/**
 * @author Administrator
 *
 */
public class TestDecorator {

    public static void main(String[] args) {
        Human human = new Man();
        human = new HairstyleDecorator(human);
        human.printDescription();
        
        human = new YellowskinDecorator(human);
        human.printDescription();
        
        human = new WalkingDecorator(human);
        human.printDescription();
        
        System.out.println("------------------------");
        
        Human human1 = new Woman();
        human1 = new YellowskinDecorator(human1);
        human1.printDescription();
        
        human1 = new HairstyleDecorator(human1);
        human1.printDescription();
        
        human1 = new WalkingDecorator(human1);
        human1.printDescription();
    }
}

运行结果：

长头发-男人
黄皮肤-长头发-男人
黄皮肤-长头发-男人
-在散步
------------------------
黄皮肤-女人
长头发-黄皮肤-女人
长头发-黄皮肤-女人
-在散步