Задача решена, правильный код сюда по правилам не выкладываю. Вопрос вот в чем: почему нельзя было решить через switch, используя имя класса?

package com.javarush.task.task14.task1415;

import java.util.ArrayList;
import java.util.List;

/*
Клининговый центр
*/

public class Solution {
    public static void main(String[] args) {
        List<Apartment> apartments = new ArrayList<Apartment>();
        apartments.add(new OneRoomApt());
        apartments.add(new TwoRoomApt());
        apartments.add(new ThreeRoomApt());

        cleanAllApartments(apartments);
    }

    public static void cleanAllApartments(List<Apartment> apartments) {
        //написать тут вашу реализацию пунктов 1-4
        for (Apartment apartment :
                apartments) {
            /*String name = apartment.getClass().getSimpleName();
            switch (name){
                case "OneRoomApt":
                    ((OneRoomApt)apartment).clean1Room();
                    break;
                case "TwoRoomApt":
                    ((TwoRoomApt)apartment).clean2Rooms();
                    break;
                case "ThreeRoomApt":
                    ((ThreeRoomApt)apartment).clean3Rooms();
                    break;
            }*/

        }
    }

    static interface Apartment {
    }

    static class OneRoomApt implements Apartment {
        void clean1Room() {
            System.out.println("1 room is cleaned");
        }
    }

    static class TwoRoomApt implements Apartment {
        void clean2Rooms() {
            System.out.println("2 rooms are cleaned");
        }
    }

    static class ThreeRoomApt implements Apartment {
        void clean3Rooms() {
            System.out.println("3 rooms are cleaned");
        }
    }
}