我对java继承有相当基本的了解。有人能解释一下应该怎么做吗？

这个问题是在我最近的编码回合中提出的

我必须打印以下行：

My name is Fastfood. My name is Fruits. Our superclass is Food I'm serving Fastfood I'm serving Fruit

---

我试了很多次，经过一个小小的修改，我得到了解决方案

class FoodFactory  extends Solution
{
    public Food getFood(String string) 
    {
        return new Food(string);
    }
}

class Food extends Solution
{
    String name=null;
    public Food(String string) 
    {
        this.name=string;
    }
    public void servesFood() 
    {
        System.out.println("I'm serving "+this.name);
    }
}

class Solution
{
    public static void main (String[] args) throws java.lang.Exception
    {
        FoodFactory myFoods = new FoodFactory();
        Food food1 = myFoods.getFood("Fastfood");
        Food food2 = myFoods.getFood("Fruits");
        System.out.println("My name is: " + food1.name);
        System.out.println("My name is: " + food2.name);
        System.out.println("Our superclass is: " + food1.getClass().getName());//modification
        food1.servesFood();
        food2.servesFood();
    }}

---

我已经测试了它，它的工作如预期

`class FoodFactory extends Food {
    public Food getFood(String string) {
        if (string.equals("Fruit")) {
            return new Fruit("Fruit");
        } else {
            return new FastFood("FastFood");
        }
    }
}

class Fruit extends Food {
    public Fruit(String name1) {
        super.name = name1;
    }
}

class FastFood extends Food {
    public FastFood(String name1) {
        super.name = name1;
    }
}

class Food {
    public String name = null;
    public Food() {

    }
    public Food(String string) {
        this.name = string;
    }
    public void servesFood() {
        System.out.println("I'm serving " + this.name);
    }
}

class Solution1 {
    public static void main(String[] args) throws java.lang.Exception {
        FoodFactory myFoods = new FoodFactory();
        Food food1 = myFoods.getFood("FastFood");
        Food food2 = myFoods.getFood("Fruit");
        System.out.println("My name is: " + food1.getClass().getName());
        System.out.println("My name is: " + food2.getClass().getName());
        System.out.println("Our superclass is: "
                + food1.getClass().getSuperclass().getName());// modification
        food1.servesFood();
        food2.servesFood();
    }
}`

---

与给出的答案相似，但带有抽象食物类

class FoodFactory extends Food {
    public Food getFood(String string) {
        if (string.equals("Fruit")) {
            return new Fruit();
        } else if (string.equals("FastFood"){
            return new FastFood();
        }
        return null;
    }

    @Override
    public void servesFood() {

    }
}

class Fruit extends Food {
    @Override
    public void servesFood() {
        System.out.println("I'm serving " + getClass().getName());
    }
}

class FastFood extends Food {
    @Override
    public void servesFood() {
        System.out.println("I'm serving " + getClass().getName());
    }
}

abstract class Food {
    public abstract void servesFood();
}

class Solution1 {
    public static void main(String[] args) throws java.lang.Exception {
        FoodFactory myFoods = new FoodFactory();
        Food food1 = myFoods.getFood("FastFood");
        Food food2 = myFoods.getFood("Fruit");
        System.out.println("My name is: " + food1.getClass().getName());
        System.out.println("My name is: " + food2.getClass().getName());
        System.out.println("Our superclass is: "
                + food1.getClass().getSuperclass().getName());// modification
        food1.servesFood();
        food2.servesFood();
    }
}

---

我检查了答案，但我检查了这个结果，注意目标是所有参数的复合短语。在许多情况下，答案必然是在标记的摘录之后，而不是像我下面描述的那样使用整个类

编译成功

/*
 * My name is: Fastfood
 * My name is: Fruits
 * Our superclass is: Food
 * I'm serving Fastfood
 * I'm serving Fruits
 */

class Solution {
    public static void main(String[] argh) {
        foodFactory myFoods = new foodFactory();
        Food food1 = myFoods.getFood("Fastfood");
        Food food2 = myFoods.getFood("Fruits");
        System.out.println("My name is: " + food1.getClass().getName());
        System.out.println("My name is: " + food2.getClass().getName());
        System.out.println("Our superclass is: " + food1.getClass().getSuperclass().getName());
        food1.serveFood();
        food2.serveFood();
    }
}

// attention: from here you will have the correct use
class foodFactory extends Solution {
    public Food getFood(String food) {
        if (food.equals("Fastfood")) {
            return new Fastfood();
        } else {
            return new Fruits();
        }
    }
}

class Food extends Solution {
    public void serveFood() {
        System.out.println("I'm serving " + this.getClass().getName());
    }
}

class Fruits extends Food {
}

class Fastfood extends Food {
}

---

你是在问我们如何编写食物/快餐/水果课程吗？@NikG我正要问同样的问题xD；）什么是

解决方案

类？你能给我们看一下你的

食品

、

水果

和

快餐

课程吗？@NikG你为什么要写水果课？？？@sinisteraadi这听起来像是一个仓促编写的课堂黑板写作示例/作业出错了。如果您已经对继承有了一些了解，那么一定要询问新的或笨拙的代码。我特别为为什么所有的东西都扩展了

解决方案而烦恼。食品工厂没有理由继承食品。它不是食物，它是某种工厂。我们继承它是因为我们希望我们的超类被打印为“食物”，它是FoodFactory，所以它应该打印FoodFactory。
`class FoodFactory extends Food {
    public Food getFood(String string) {
        if (string.equals("Fruit")) {
            return new Fruit("Fruit");
        } else {
            return new FastFood("FastFood");
        }
    }
}

class Fruit extends Food {
    public Fruit(String name1) {
        super.name = name1;
    }
}

class FastFood extends Food {
    public FastFood(String name1) {
        super.name = name1;
    }
}

class Food {
    public String name = null;
    public Food() {

    }
    public Food(String string) {
        this.name = string;
    }
    public void servesFood() {
        System.out.println("I'm serving " + this.name);
    }
}

class Solution1 {
    public static void main(String[] args) throws java.lang.Exception {
        FoodFactory myFoods = new FoodFactory();
        Food food1 = myFoods.getFood("FastFood");
        Food food2 = myFoods.getFood("Fruit");
        System.out.println("My name is: " + food1.getClass().getName());
        System.out.println("My name is: " + food2.getClass().getName());
        System.out.println("Our superclass is: "
                + food1.getClass().getSuperclass().getName());// modification
        food1.servesFood();
        food2.servesFood();
    }
}`

class FoodFactory extends Food {
    public Food getFood(String string) {
        if (string.equals("Fruit")) {
            return new Fruit();
        } else if (string.equals("FastFood"){
            return new FastFood();
        }
        return null;
    }

    @Override
    public void servesFood() {

    }
}

class Fruit extends Food {
    @Override
    public void servesFood() {
        System.out.println("I'm serving " + getClass().getName());
    }
}

class FastFood extends Food {
    @Override
    public void servesFood() {
        System.out.println("I'm serving " + getClass().getName());
    }
}

abstract class Food {
    public abstract void servesFood();
}

class Solution1 {
    public static void main(String[] args) throws java.lang.Exception {
        FoodFactory myFoods = new FoodFactory();
        Food food1 = myFoods.getFood("FastFood");
        Food food2 = myFoods.getFood("Fruit");
        System.out.println("My name is: " + food1.getClass().getName());
        System.out.println("My name is: " + food2.getClass().getName());
        System.out.println("Our superclass is: "
                + food1.getClass().getSuperclass().getName());// modification
        food1.servesFood();
        food2.servesFood();
    }
}

/*
 * My name is: Fastfood
 * My name is: Fruits
 * Our superclass is: Food
 * I'm serving Fastfood
 * I'm serving Fruits
 */

class Solution {
    public static void main(String[] argh) {
        foodFactory myFoods = new foodFactory();
        Food food1 = myFoods.getFood("Fastfood");
        Food food2 = myFoods.getFood("Fruits");
        System.out.println("My name is: " + food1.getClass().getName());
        System.out.println("My name is: " + food2.getClass().getName());
        System.out.println("Our superclass is: " + food1.getClass().getSuperclass().getName());
        food1.serveFood();
        food2.serveFood();
    }
}

// attention: from here you will have the correct use
class foodFactory extends Solution {
    public Food getFood(String food) {
        if (food.equals("Fastfood")) {
            return new Fastfood();
        } else {
            return new Fruits();
        }
    }
}

class Food extends Solution {
    public void serveFood() {
        System.out.println("I'm serving " + this.getClass().getName());
    }
}

class Fruits extends Food {
}

class Fastfood extends Food {
}