Java 如何传递需要Food类型参数的参数？

我正在编写一个基于继承演示的程序。我正在尝试编写一个异常，以便唯一可以传递到链接到Wolf类的Meat类的参数。本质上，我试图允许唯一可以传递到eating方法中的参数是一个名为Meat的食物变量。代码如下：

动物

abstract public class Animal 
{

String name;
int age;  
String noise;

abstract public void makeNoise();

public String getName() {
        return name;
    }

    public void setName(String newName) {
        name = newName;
    }

abstract public Food eat(Food x) throws Exception;

}

食物

public class Food {

    //field that stores the name of the food
    public Food name; 

    //constructor that takes the name of the food as an argument
    public Food(Food name){
        this.name = name;
    }

    public Food getName() {
        return name;
    }
}

肉

public class Meat extends Food 
{

    public Meat(Food name) 
    {
        super(name);
    }

    public Food getName() 
{
    return super.getName();
}
}

食肉动物

public class Wolf extends Carnivore
{

Wolf()   
{
    name = "Alex";
    age = 4;

}
    public void makeNoise()  
    {
        noise = "Woof!";
    }
    public String getNoise()  
    {
        return noise;
    }
    public String getName() 
    {
        return name;
    }  
    public int getAge()
    {
        return age;
    }

    public Food eat(Food x) throws Exception
    { 
        if (x instanceof Meat) {
                return x;
            } else {
               throw new Exception("Carnivores only eat meat!");
            }
    }    
}

狼

public class Wolf extends Carnivore
{

Wolf()   
{
    name = "Alex";
    age = 4;

}
    public void makeNoise()  
    {
        noise = "Woof!";
    }
    public String getNoise()  
    {
        return noise;
    }
    public String getName() 
    {
        return name;
    }  
    public int getAge()
    {
        return age;
    }

    public Food eat(Food x) throws Exception
    { 
        if (x instanceof Meat) {
                return x;
            } else {
               throw new Exception("Carnivores only eat meat!");
            }
    }
}

Main

public class Main {

    public static void main(String[] args) 
    {

        Wolf wolfExample = new Wolf();        
        System.out.println("************Wolf\"************");
        System.out.println("Name = " + wolfExample.getName());
        System.out.println("Age = " + wolfExample.getAge());
        wolfExample.makeNoise();
        System.out.println("Noise = " + wolfExample.getNoise());

        Meat meatExample = new Meat(//Food argument goes here?);
        System.out.println("************Wolf eating habits************");
        System.out.println("Wolves eat " + wolfExample.eat(meatExample.getName()));
    }
}

---

我遇到的问题是，我不能在我在主方法中创建的新肉类对象中传递任何食物参数。当我试图调用

System.out.println（“Wolfs eat”+wolfExample.eat（meatExample.getName（）））时，我会得到一个不受支持的异常错误首先，您的食肉类和狼类是相同的

您尚未传递“meatExample”的名称

并尝试实例化肉类对象并在Food类中分配它

Food meatExample = new Meat("Beef");

通过这种方式，您调用的是食品类的getName（）方法，而不是来自肉类类。
基本上，您的
Food
和
Meat
类设计不正确，需要如下所示进行修复，即
Meat
类应采用食品
name
属性的参数

食品类：

public abstract class Food {

    //field that stores the name of the food
    protected String name; 

    public String getName() {
        return this.name;
    }
}

public class Meat extends Food {

    public Meat(String name) {
        super.name = name;
    }

    //other methods or add other specific meat fields
}

public static void main(String[] args) {

        //Create the Meat Object by sending the name in constructor
        Meat meatExample = new Meat("Chicken");
        //other code
}

肉类类别：

public abstract class Food {

    //field that stores the name of the food
    protected String name; 

    public String getName() {
        return this.name;
    }
}

public class Meat extends Food {

    public Meat(String name) {
        super.name = name;
    }

    //other methods or add other specific meat fields
}

public static void main(String[] args) {

        //Create the Meat Object by sending the name in constructor
        Meat meatExample = new Meat("Chicken");
        //other code
}

main（）方法：

public abstract class Food {

    //field that stores the name of the food
    protected String name; 

    public String getName() {
        return this.name;
    }
}

public class Meat extends Food {

    public Meat(String name) {
        super.name = name;
    }

    //other methods or add other specific meat fields
}

public static void main(String[] args) {

        //Create the Meat Object by sending the name in constructor
        Meat meatExample = new Meat("Chicken");
        //other code
}

你必须先修改你的动物和食物类，然后在你的主类中做一些其他的改变，你也许能够达到你想要达到的目标。以下是一些建议的修改：

public class Food {

    //field that stores the name of the food
    public String name; 

    //constructor that takes the name of the food as an argument
    public Food(String name){
        this.name = name;
    }

    public String getName() {
        return name;
    }
}

public class Meat extends Food 
{
    public Meat(String name) {
        super(name);
    }

    public String getName() {
        return super.getName();
    }
}


public class Main {
    public Main() {
        super();
    }

    public static void main(String[] args) {
        Wolf wolfExample = new Wolf();        
          System.out.println("************Wolf\"************");
          System.out.println("Name = " + wolfExample.getName());
          System.out.println("Age = " + wolfExample.getAge());
          wolfExample.makeNoise();
          System.out.println("Noise = " + wolfExample.getNoise());

        try {            
            Meat meatExample = new Meat("Steak");
            //Food vegFood =  new Food("Spinach");
                    System.out.println("************Wolf eating habits************");
            wolfExample.eat(meatExample);
            //wolfExample.eat(vegFood);

        } catch (Exception e) {
            // TODO: Add catch code
            e.printStackTrace();
        }
    }
}

所以，如果你调用
wolfExample.eat（vegFood）您的代码将引发异常
 您应该修复混乱的缩进。只需传递meatExample而不是meatExample.getName（）。
Meat-meatExample=new-Meat（//此处是Food参数？）
仍然需要传递一个我仍然不确定的Food参数。我认为应该与它正在查找Food变量和已传递的String变量这一事实分开，因此我收到错误消息
String无法转换为Food
？