如何给不同的arraylist赋值？

Question

我正在做一个餐厅模拟项目。但是，我卡在了代码的反馈部分。我从顾客那里拿了食物给 ArrayList，关于这个 ArrayList，程序可以针对每种食物一个一个地提出问题，并从顾客那里获取一个评分值。但是我不能将它们放入不同的 ArrayLists 中。我想这样做是因为关于食物的比率，程序应该显示评分最高的食物。

简而言之，我想对不同的数组进行排序。

public static ArrayList FeedBack(ArrayList<String> foods) {
    int foodtype;
    int rate;
    for (int i = 0; i < foods.size(); i++) {
        System.out.printf("%s", foods.get(i));
        System.out.println("");
        System.out.println("please rate that food out of 5");
        Scanner feedbackk = new Scanner(System.in);
        rate = feedbackk.nextInt();
        if ((foods.get(i)).equals("Fried Fries")) {

            RateOfFriedFries.add(rate);
            AllTheFoodRates.add(RateOfFriedFries);
        } else if (foods.get(i).equals("Meat Bal")) {
            RateOfMeatBall.add(rate);
            AllTheFoodRates.add(RateOfMeatBall);
        }
    }
    return AllTheFoodRates;
}

Answer 1

按如下操作：

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Scanner;

public class Main{
    public static void main(String[] args) {
        //Test
        List<String> foods=Arrays.asList("Fried Fries","Meat Bal");
        System.out.println(feedBack(foods));
    }
    public static List<ArrayList> feedBack(List<String> foods){
        int foodType;
        int rating;
        List<ArrayList> ratingOfAllFoods=new ArrayList<ArrayList>();
        List<Integer> ratingOfFriedFries=new ArrayList<Integer>();
        List<Integer> ratingOfMeatBall=new ArrayList<Integer>();
        for(int i=0;i<foods.size();i++)        {
            System.out.printf("%s%n",foods.get(i));
            System.out.print("Please rate that food out of 5: ");
            Scanner feedback=new Scanner(System.in);
            if(feedback.hasNextInt()) {
                rating=feedback.nextInt();
                if ("Fried Fries".equals(foods.get(i))) {
                    ratingOfFriedFries.add(rating);
                    ratingOfAllFoods.add((ArrayList) ratingOfFriedFries);
                }
                else if("Meat Bal".equals(foods.get(i))){
                    ratingOfMeatBall.add(rating);
                    ratingOfAllFoods.add((ArrayList) ratingOfMeatBall);
                }
              } else {
                  System.out.println("Invalid input");
              }
        }
        return ratingOfAllFoods;
    }
}

样本运行:

Fried Fries
Please rate that food out of 5: 3
Meat Bal
Please rate that food out of 5: 4
[[3], [4]]

我还建议您遵循变量和函数的命名约定。

如何给不同的arraylist赋值？

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