设计模式-装饰模式

装饰模式：动态的给对象扩展功能，提供了比继承更为弹性的替代方案。详情看代码

/**
 * Created by apple on 2018/10/17.
 */
public interface CarService {

    public double takeCosts();

    public String takeServiceName();
}

/**
 * Created by apple on 2018/10/17.
 */
public abstract class CommonService implements CarService {

    protected CarService carService;

    public CommonService(CarService carService) {
        this.carService = carService;
    }

}

/**
 * Created by apple on 2018/10/17.
 */
public class MetaSheetService extends CommonService {

    public MetaSheetService(CarService carService) {
        super(carService);
    }

    @Override
    public double takeCosts() {
        return carService.takeCosts()+ 135.0;
    }

    @Override
    public String takeServiceName() {
        return carService.takeServiceName()+ ","+ "钣金";
    }
}

/**
 * Created by apple on 2018/10/17.
 */
public class RefitService extends CommonService {

    public RefitService(CarService carService) {
        super(carService);
    }

    @Override
    public double takeCosts() {
        return carService.takeCosts()+ 235.0;
    }

    @Override
    public String takeServiceName() {
        return carService.takeServiceName()+ "," + "改装";
    }
}

/**
 * Created by apple on 2018/10/17.
 */
public class WashCarService implements CarService {
    @Override
    public double takeCosts() {
        return 30.0;
    }

    @Override
    public String takeServiceName() {
        return "洗车";
    }
}

/**
 * Created by apple on 2018/10/17.
 */
public class Main {

    public static void main(String[] args){
        WashCarService washCarService = new WashCarService();
        System.out.println(washCarService.takeCosts());
        System.out.println(washCarService.takeServiceName());

        MetaSheetService metaSheetService  = new MetaSheetService(washCarService);
        System.out.println(metaSheetService.takeCosts());
        System.out.println(metaSheetService.takeServiceName());

        RefitService refitService  = new RefitService(metaSheetService);
        System.out.println(refitService.takeCosts());
        System.out.println(refitService.takeServiceName());

    }
}