Java层次结构和对象数组

我有很多关于这段代码的问题，这段代码是我为一个学校项目写的。我正在尝试这样做：

创建并实现一个类层次结构，其中Vehicle超类、“Motorcycle”和“Truck”是子类

• 摩托车和卡车共有的变量是车轮和重量以及方法显示（）。属性不应在类外部可访问。display（）将打印轮子和重量，并且应该仅对公共类和所有子类都可以访问
• 摩托车等级特有的数据应为乘客。卡车类别特有的数据应为有效载荷。包括显示此信息的方法
• 绘制类层次结构
• 创建一个“驱动程序”类来测试您的层次结构。允许用户通过在车辆阵列中存储参考来创建多个对象。您应该允许用户通过输入“m”来创建摩托车对象，然后请求相关属性。沿相同的直线，使用“t”创建卡车对象
• 输入所有数据后，通过调用display（）方法打印出每个对象的内容。如果是摩托车，则打印乘客人数；如果是卡车，则打印有效载荷。注意，display（）方法必须为不同的子类重写

这是我的原始代码：

import java.util.Scanner;
class Hierarchy{
    public static void main(String[] args){
        Scanner in = new Scanner(System.in);
        Vehicle [] garage = new Vehicle [3];
        for(int i = 0; i< garage.length;i++){
            System.out.println("Please enter 't' to create a truck, and 'm' for a motorcycle");
            String charIn = in.nextLine();
            if(charIn == "m"){
                System.out.println("What is the payload of the Truck");
                int payload = in.nextInt();
                System.out.println("What is the weight of the Truck");
                int weight = in.nextInt();
                System.out.println("How many wheels does the Truck have");
                int wheels = in.nextInt();
                garage[i] = new Truck(payload, wheels, weight);
            }else{
                System.out.println("How many passengers can the Motorcycle seat");
                int passengers = in.nextInt();
                System.out.println("What is the weight of the Motorcycle");
                int weight = in.nextInt();
                System.out.println("How many wheels does the Motorcycle have");
                int wheels = in.nextInt();
                garage[i] = new Motorcycle(passengers, weight, wheels);
            }
        }
        //display();
    }
}


class Vehicle{
    int wheels;
    int weight;
    public Vehicle(int wheels, int weight){
        weight = this.weight;
        wheels = this.wheels;
    }
    //private void display(int weight, int passengers, int wheels){
    //}
    //private void display(int weight, int payload, int wheels){
    //}

}

class Truck extends Vehicle{
    int payload;
    public int getWheels(){
        return wheels;
    }
    public int getWeight(){
        return weight;
    }
    public Truck(int wheels, int payload, int weight){
        super(wheels, weight);
        this.payload = payload;
    }
}

class Motorcycle extends Vehicle{
    int passengers;
    public int getWheels(){
        return wheels;
    }
    public int getWeight(){
        return weight;
    }
    public Motorcycle(int wheels, int passengers, int weight){
        super(wheels, weight);
        this.passengers = passengers;
    }
}

import java.util.Scanner；
类层次结构{
公共静态void main（字符串[]args）{
扫描仪输入=新扫描仪（系统输入）；
车辆[]车库=新车[3]；
对于（int i=0；i

我尝试了尽可能多地查找资源，但是我看不到一种方法可以将数据输入到超类和子类中，然后将信息放入一个对象（车库数组）。还有，谁能给我一些方法来打印车库阵列对象中的数据？当然，如果你看到任何愚蠢的错误，请随时告诉我。

---

非常感谢你的帮助

从以下内容开始：

class Vehicle {
    int wheels;
    int weight;
    public Vehicle(int wheels, int weight){
        this.weight = weight;
        this.wheels = wheels;
    }

    public int getWheels() {
        return wheels;
    }

    public int getWeight() {
        return weight;
    }
}

class Truck extends Vehicle {
    int payload;

    public Truck(int wheels, int payload, int weight){
        super(wheels, weight);
        this.payload = payload;
    }

    public String toString() {
        // todo - write code to output the truck details as a string
        return "truck details here";
    }
}

class Motorcycle extends Vehicle{
    int passengers;

    public Motorcycle(int wheels, int passengers, int weight){
        super(wheels, weight);
        this.passengers = passengers;
    }

    public String toString() {
        // todo - write code to output the motorcycle details as a string
        return "motorcycle details here";
    }
}

创建卡车和摩托车并将它们放入车辆数组的代码看起来很好

当您想要打印它们时，只需在每个对象上循环调用toString的数组并打印出来：

for(Vehicle vehicle : garage) {
    System.out.println(vehicle.toString());
}

---

此外，您还可以测试charIn='m'是否创建了一辆卡车而不是摩托车。如果用户输入的不是

m

，那么您就创建了一个摩托车。

为了很好地打印数组，

arrays.toString（someArray）

是您的朋友。