装饰模式

装饰模式(Decorator)：动态的给一个对象添加一些额外的职责，就增加功能来说，装饰模式比生成子类更为灵活。

装饰模式是为已有功能动态地添加更多功能的一种方式。装饰模式提供了非常好的解决方案，它把每个装饰功能放在单独的类中，并让这个类包装它所要装饰的对象，因此，当需要执行特殊行为时，客户代码就可以在运行时根据需要有选择地、按顺序地使用装饰功能包装对象。

装饰模式的优点：把类中的装饰功能从类中搬移去除，这样可以简化原有的类。有效地把类的核心职责和装饰功能区分开了。而且可以去除相关类中重复的装饰逻辑。

People.java类

package decorate;


public class People{
    private String name;
    
    public People() {
    }
    public People(String name) {
        this.name = name;
    }

    public void operation() {
        System.out.println("开始装饰："+name);
    }
}

Finery.java类

package decorate;

public class Finery extends People{
    private People people;
    
    public void decorate(People people) {
        this.people = people;
    }

    public void operation(){
        people.operation();
    }
}

TshirtFinery.java类

package decorate;

public class TshirtFinery extends Finery {

    @Override
    public void operation() {
        super.operation();
        this.show();

    }
    public void show(){
        System.out.println("大T衫");
    }

}

BigTrouserFinery.java类

package decorate;

public class BigTrouserFinery extends Finery {
    @Override
    public void operation() {
        super.operation();
        this.show();
        
    }
    public void show(){
        System.out.println("大裤衩");
    }
}

ShoeFinery.java类

package decorate;

public class ShoeFinery extends Finery {
    @Override
    public void operation() {
        super.operation();
        this.show();
        
    }
    public void show(){
        System.out.println("长袜子");
    }
}

Business.java类

package decorate;

public class Business {
    public static void main(String[] args) {
        People p = new People("桂清");
        TshirtFinery t = new TshirtFinery();
        BigTrouserFinery b = new BigTrouserFinery();
        ShoeFinery s = new ShoeFinery();
        t.decorate(p);
        b.decorate(t);
        s.decorate(b);
        s.operation();

    }
}