Question

所以我正在制作一个模仿真正的自动售货机的程序，我遇到了一些麻烦。这是该计划的标准。必须，

从用户输入的文件中读取。
读取文件后，显示每个文件的项目和价格。
为每个项目指定一个坐标，就像真正的自动售货机一样（例如A1，B3，C4等）。
询问用户他们想要什么项目并让他们输入坐标。
然后让他们输入他们的钱然后给予改变或要求他们输入更多的钱。

我已经弄清楚如何将价格放在一个数组中并显示它们，但这就是我所得到的。请帮忙！我的代码可以在下面看到！

import java.util.*;
import java.io.File;
import java.io.FileNotFoundException;

public class Vending2 
{
  public static void main(String[] args) throws FileNotFoundException
  {
      System.out.print("Enter your food selection file: ");      // User inputs file
      Scanner input = new Scanner(System.in);                       // Keyboard input from user
      String filename = input.nextLine();
      Scanner fs = new Scanner(new File(filename));         // Scans in the file that was inputed



        String line;
        double price;
        int num = 0;
        while(fs.hasNextLine()){
             line = fs.nextLine();
             price = Double.parseDouble(line.split(" ")[0]);
             num++;
        }

        fs.close();
        fs = new Scanner(new File(filename));

        double[] value = new double[num];                        //Array for prices
        int i = 0;
        while(fs.hasNextLine()){
             line = fs.nextLine();
             price = Double.parseDouble(line.split(" ")[0]);
             value[i] = price;
             i++;
        }
        System.out.println(Arrays.toString(value));
  }
}

以下是我正在阅读的文件：

1.00 Honey roasted peanuts
1.50 Cheetos
1.50 Bugles
2.00 Synder’s Pretzels
1.00 Snickers
1.00 Twix
1.25 M n Ms
.75 Life savers
1.00 Twizzlers
1.00 Nutter Butters
1.00 Butter Fingers
1.50 King Size Kit Kats
1.25 Carrot sticks
.50 Juicy Fruit
.50 Spearmint Gum
0.50 Five gum
3.50 Pepperoni
1.75 Cheez-Its
.25 Slim Jim
1.50 Lays Barbeque Chips

Answer 1

1）创建一个名为FoodItem的类，其中包含名称和价格

2）用“”分隔文件中的行并填充名称＆amp;价

3）将FoodItem添加到foodItemsList

4）遍历List并打印值。

我使用该列表假设食品名称中可能存在重复项。如果没有，请将List更改为HashMap。

import java.util.*;
import java.io.File;
import java.io.FileNotFoundException;

public class Vending2 {
    public static void main(String[] args) throws FileNotFoundException {
        System.out.print("Enter your food selection file: "); // User inputs
                                                                // file
        Scanner input = new Scanner(System.in); // Keyboard input from user
        String filename = input.nextLine();
        Scanner fs = new Scanner(new File(filename)); // Scans in the file that
                                                        // was inputed

        String line;
        double price;
        List<FoodItem> foodItemsList = new ArrayList<FoodItem>();

        while (fs.hasNextLine()) {
            line = fs.nextLine();
            String[] itemsWithPrice;
            itemsWithPrice = line.split(" ");
            if (itemsWithPrice.length > 1){
                price = Double.parseDouble(itemsWithPrice[0]);
                String name="";
                for (int i=1; i<itemsWithPrice.length;i++){
                    name +=     itemsWithPrice[i];              
                }
                foodItemsList.add(new FoodItem(name,price));
            }
        }
        System.out.println("Food List");
        for (int i=0; i< foodItemsList.size(); i++){
            System.out.println(foodItemsList.get(i));
        }
    }

}

class FoodItem{
    String name;
    double price;
    public FoodItem(String name, double price){
        this.name = name;
        this.price = price;
    }
    public String toString(){
        return new StringBuffer().append("name:").append(name).append(":").append("price:").append(price).toString();
    }
}

输出：

输入您的食物选择文件：v1.txt

食物清单

name:Honeyroastedpeanuts:price:1.0
name:Cheetos:price:1.5
name:Bugles:price:1.5
name:SynderÆsPretzels:price:2.0
name:Snickers:price:1.0
name:Twix:price:1.0
name:MnMs:price:1.25
name:Lifesavers:price:0.75
name:Twizzlers:price:1.0
name:NutterButters:price:1.0
name:ButterFingers:price:1.0
name:KingSizeKitKats:price:1.5
name:Carrotsticks:price:1.25
name:JuicyFruit:price:0.5
name:SpearmintGum:price:0.5
name:Fivegum:price:0.5
name:Pepperoni:price:3.5
name:Cheez-Its:price:1.75
name:SlimJim:price:0.25
name:LaysBarbequeChips:price:1.5

自动售货机模拟器，读取文件并使用数组

1 个答案: