java - IOException 循环

Question

我需要帮助弄清楚如何循环我的IOException（在我要求文件名的地方，直到输入有效的文件名）。我需要一个循环来以某种方式识别输入了无效文件并且不确定如何执行此操作。

import java.util.*;
import java.io.*;
public class JavaGradedLab {
    public static void main(String[] args) throws IOException {

        Scanner inScan, fScan = null;
        int [] A = new int[5];
        inScan = new Scanner(System.in);
        System.out.println("Please enter the file to read from: ");

        try{
            String fName = inScan.nextLine();
            fScan = new Scanner(new File(fName));
        }

        catch (FileNotFoundException ex)
        {
            System.out.println("Your file is invalid -- please re-enter");
        }

        String nextItem;
        int nextInt = 0;
        int i = 0;

        while (fScan.hasNextLine())
        {
            nextItem = fScan.nextLine();
            nextInt = Integer.parseInt(nextItem);
            A[i] = nextInt;
            i++;
        }

        System.out.println("Here are your " + i + " items:");
        for (int j = 0; j < i; j++)
        {
            System.out.println(A[j] + " ");
        }
    }
}

Answer 1

好吧，肯定会有人解释如何通过最佳实践等来改进您的代码，但作为一个非常基本的答案，它本身可能会得到改进（假设您的代码在输入有效时工作）：

while(true) {
    try{
        String fName = inScan.nextLine();
        fScan = new Scanner(new File(fName));
        break;
    }
    catch (FileNotFoundException ex)
    {
        System.out.println("Your file is invalid -- please re-enter");
    }
}