Java装饰模式

首先，直接代码说话

　　

//广阔的空间里，到处都是美好的气息
interface  BroadItch{
    void getItch();

}

//我们可以直接去个好地方
class Library implements BroadItch{
    @Override
    public void getItch() {
        System.out.println("图书馆看书好舒服!");
    }
}

//也可以创造个工具，帮我们导引去找个地方
class HomeBuilder implements  BroadItch{

    private BroadItch broadItch;//保持对抽象的引用

    public HomeBuilder(BroadItch broadItch) {
        this.broadItch = broadItch;
    }

    public void getItch() {
        broadItch.getItch();
    }

}

//用工具去找个学校
class School extends HomeBuilder{

    public School(BroadItch broadItch) {
        super(broadItch);
    }

    @Override
    public void getItch() {
        System.out.println("早个学校");
    }
}

//或者去找个地方做礼拜
class Temple extends HomeBuilder {

    public Temple(BroadItch broadItch) {
        super(broadItch);
    }

    @Override
    public void getItch() {
        System.out.println("做礼拜去！");
    }
}

/**
 * Created by nicknailo on 2018/4/14.
 */
public class Decorator {

    public static void main(String args[]) {

        BroadItch aa,bb,bb1,cc,cc1;

        aa = new Library();
        aa.getItch();
        System.out.println("---------------------");
        bb = new School(aa);
        bb1 = new HomeBuilder(bb);
        bb1.getItch();
        System.out.println("---------------------");
        cc = new Temple(bb1);
        cc1 = new HomeBuilder(cc);
        cc1.getItch();


    }

}

　　结果输出

装饰者模式，针对单个对象，需要我们外部构造一个装饰者，然后把我们需要的示例加入装饰者的构造中，程序依次直接调用，外部看不出来，对象是怎么运行的。