如何添加输入到继承

Question

对不起，如果这是有点令人困惑，第一次使用本网站，所以我不知道我是否正确输入我的代码。所以我的问题是，当我运行这个程序的类驱动程序我得到这个：

name: No Name Yet 
Manufacturer: no name yet 
Engine Cyclinders: 0 
Load: 0.0 
Towing: 0.0 

这是默认的，现在我想可以把输入的类驱动程序，这将改变说这个名字例如，我将其设置为Person。我尝试过使用p.setName("Tim")，但如果我拨打Person的writeouput方法，它只会显示名称tim。如果我打电话给班级卡车writeoutput，那么它说没有名字。我把writeoutput放在超级，但我不知道我做错了什么。任何帮助，将不胜感激

public class Person { 

    private String name; 

    public Person() 
    { 
     name = "No Name Yet"; 
    } 
    public Person(String initialName) 
    { 
     name = initialName; 
    } 
    public void setName(String newName) 
    { 
     newName = "tim"; 
     name = newName; 
    } 
    public String getName() 
    { 
     return name; 
    } 
    public void writeOutput() 
    { 
     System.out.println("name: " + name); 
    } 
    public boolean hasSameName(Person otherPerson) 
    { 
     return this.name.equalsIgnoreCase(otherPerson.name); 
    } 

} 
public class Vehicle extends Person { 

    String manufactName; 
    int engine; 



    public Vehicle() 
    { 
     manufactName = "no name yet"; 
     engine = 0; 
    } 
    public Vehicle(String initialManufactName, int initialEngine) 
    { 
     manufactName = initialManufactName; 
     engine = initialEngine; 
    } 
    public void setManufactName(String newManufactName) 
    { 
     manufactName = newManufactName; 
    } 
    public void setEngine(int newEngine) 
    { 

     engine = newEngine; 
    } 
    public String getManufactName() 
    { 

     return manufactName; 
    } 
    public double getEngine() 
    { 
     return engine; 
    } 
    public void writeOutput() 
    { 
     super.writeOutput(); 
     System.out.println("Manufacturer: " + manufactName); 
     System.out.println("Engine Cyclinders: " + engine); 
    } 
    public boolean hasSameManufactName(Vehicle otherVehicle) 
    { 
     return this.manufactName.equalsIgnoreCase(otherVehicle.manufactName); 
    } 
    public boolean hasSameEngine(Vehicle otherVehicle) 
    { 
     return this.engine == (otherVehicle.engine); 
    } 
} 

public class Truck extends Vehicle { 

    private double load; 
    private double towing; 

    public Truck() 
    { 
     load = 0; 
     towing = 0; 
    } 
    public Truck(double initialLoad, double initialTowing) 
    { 
     load = initialLoad; 
     towing = initialTowing; 
    } 
    public void setLoad(double newLoad) 
    { 
     load = newLoad; 
    } 
    public void setTowing(double newTowing) 
    { 
     towing = newTowing; 
    } 
    public double getLoad() 
    { 
     return load; 
    } 
    public double getTowing() 
    { 
     return towing; 
    } 
    public void writeOutput() 
    { 
     super.writeOutput(); 
     System.out.println("Load: " + load); 
     System.out.println("Towing: " + towing); 
    } 
    public boolean hasSameLoad(Truck otherTruck) 
    { 
     return this.load == (otherTruck.load); 
    } 
    public boolean hasSameTowing(Truck otherTruck) 
    { 
     return this.towing == (otherTruck.towing); 
    } 
} 

public class Driver extends Truck{ 
    public static void main(String[] args){ 
     Person p = new Person(); 
     Vehicle v = new Vehicle(); 
     Truck t = new Truck(); 
     t.writeOutput(); 
    } 

}

Answer 1

你并不需要在层次结构中创建的每个类的一个实例。

尝试：

Truck t = new Truck(); 
t.setName("tim"); 
t.writeOutput(); 

而且，你的设计是奇数：车辆通常不会继承一个人，和驱动程序通常不会继承一个卡车。一个Driver将是Person的一个子类。一辆卡车将是一辆车的一个子类，一辆车将拥有一辆车。