java达达租车系统，菜鸟一枚，希望大家能给些批评建议

汽车类，客车、货车、皮卡车继承这个类

public class Car {
    String name;
    int price;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getPrice() {
        return price;
    }

    public void setPrice(int price) {
        this.price = price;
    }
}

客车类

public class PassengerCar extends Car {
    private int passengerNum;

    public PassengerCar(String name, int i, int passengerNum) {
        super();
        super.setName(name);
        super.setPrice(i);
        this.passengerNum = passengerNum;
    }

    public int getPassengerNum() {
        return passengerNum;
    }

    public void setPassengerNum(int passengerNum) {
        this.passengerNum = passengerNum;
    }

    @Override
    public String toString() {
        return this.getName() + "\t" + this.getPrice() + "元/天\t载客" + passengerNum + "人";
    }
}

货车类

public class Truck extends Car {
    private int goodsNum;

    public Truck(String name, int price, int goodsNum) {
        super();
        super.setName(name);
        super.setPrice(price);
        this.goodsNum = goodsNum;
    }

    public int getGoodsNum() {
        return goodsNum;
    }

    public void setGoodsNum(int goodsNum) {
        this.goodsNum = goodsNum;
    }

    @Override
    public String toString() {
        return this.name + "\t" + price + "元/天\t载货" + goodsNum + "T";
    }
}

皮卡车类

public class PickUp extends Car {
    private int passengerNum;
    private int goodsNum;

    public PickUp(String name, int price, int passengerNum, int goodsNum) {
        super();
        super.setName(name);
        super.setPrice(price);
        this.passengerNum = passengerNum;
        this.goodsNum = goodsNum;
    }

    public int getPassengerNum() {
        return passengerNum;
    }

    public void setPassengerNum(int passengerNum) {
        this.passengerNum = passengerNum;
    }

    public int getGoodsNum() {
        return goodsNum;
    }

    public void setGoodsNum(int goodsNum) {
        this.goodsNum = goodsNum;
    }

    @Override
    public String toString() {
        return this.getName() + "\t" + this.getPrice() + "元/天\t载客" + passengerNum + "人\t载货" + goodsNum + "T";
    }

}

出租的逻辑代码

public class Lease {
    @SuppressWarnings({ "null", "null", "null", "null" })
    public static void main(String[] args) {
        System.out.println("欢迎使用哒哒租车系统\n您是否要租车：1是 0否");
        @SuppressWarnings("resource")
        Scanner input = new Scanner(System.in);
        if (input.nextInt() != 1) {
            return;
        }
        System.out.println("您可租车的类型及价目表");
        System.out.println("序号 汽车名称 租金 容量");
        // 初始化车辆信息
        PassengerCar car = new PassengerCar("奥迪A4", 500, 4);
        PassengerCar car2 = new PassengerCar("马自达6", 400, 4);
        PickUp car3 = new PickUp("皮卡雪6", 450, 4, 2);
        PassengerCar car4 = new PassengerCar("金龙", 800, 20);
        Truck car5 = new Truck("松花江", 400, 4);
        Truck car6 = new Truck("依维柯", 1000, 20);
        Car[] cars = { car, car2, car3, car4, car5, car6 };
        // 展示车辆信息
        for (int i = 0; i < cars.length; i++) {
            System.out.println((i + 1) + ".\t" + cars[i].toString());
        }

        System.out.println("请输入您要租汽车的数量：");
        // 记录租车数量
        int num = input.nextInt();
        // 记录租车的序号
        int[] carsNO = new int[num];
        for (int i = 0; i < num; i++) {
            System.out.println("请输入第" + (i + 1) + "辆车的序号:");
            int key = input.nextInt();
            if (key >= 1 && key <= 6) {
                carsNO[i] = key;
            } else {
                System.out.println("您输入的序号有误，请重新输入");
                i--;//输入错误序号后，增加一次循环
            }
        }

        // 总金额，总载客量，总载货量
        int totalPrice = 0, totalPassengerNum = 0, totalGoodsNum = 0;
        // 记录租车的车名
        StringBuffer passengerName = new StringBuffer();
        StringBuffer truckName = new StringBuffer();

        for (int j = 0; j < carsNO.length; j++) {
            switch (carsNO[j]) {
            case 1:
                passengerName.append(car.getName() + "   ");
                totalPrice += car.getPrice();
                totalPassengerNum += car.getPassengerNum();
                break;
            case 2:
                passengerName.append(car2.getName() + "   ");
                totalPrice += car2.getPrice();
                totalPassengerNum += car2.getPassengerNum();
                break;
            case 3:
                passengerName.append(car3.getName() + "   ");
                truckName.append(car3.getName() + "   ");
                totalPrice += car3.getPrice();
                totalPassengerNum += car3.getPassengerNum();
                totalGoodsNum += car3.getGoodsNum();
                break;
            case 4:
                passengerName.append(car4.getName() + "   ");
                totalPrice += car4.getPrice();
                totalPassengerNum += car4.getPassengerNum();
                break;
            case 5:
                truckName.append(car5.getName() + "   ");
                totalPrice += car5.getPrice();
                totalGoodsNum += car5.getGoodsNum();
                break;
            case 6:
                truckName.append(car6.getName() + "   ");
                totalPrice += car6.getPrice();
                totalGoodsNum += car6.getGoodsNum();
                break;
            default:
                break;
            }
        }

        System.out.println("请输入租车天数：");
        int days = input.nextInt();
        // 输出最后信息
        System.out.println("您的账单：\n***可载人的车有：");
        System.out.println(passengerName + "共载人：" + totalPassengerNum + "人");
        System.out.println("***载货的车有：");
        System.out.println(truckName + "共载货：" + totalGoodsNum + "吨");
        System.out.println("***租车的总价格：" + days * totalPrice + "元");
        System.out.println("感谢您使用哒哒租车系统");
    }
}