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我的Java代码无法编译-我出错了,我也不明白为什么

[英]My Java code would not compile- I am having an error and i don't understand why

package test;

   /* Read numbers from a text file and store them into an array; then
  sort the array and display it on the screen. Save the sorted array
in sorted.txt. */ 

import java.util.Scanner;
import java.io.*;

public class Test {

 static public void main(String[] args) throws IOException {

    /* Initialize the input stream reading from a text file */

Scanner inputFile; 
    inputFile = new Scanner(new File("arrayex1.txt"));

    /* Initialize the output stream writing into a text file */

PrintWriter outputFile;
outputFile = new PrintWriter(new FileWriter("sorted.txt"));

    /* Declare the array */

int[] numbers = new int[50];
int index = 0;

    int temp, smallest, smallest_index;

    /* Read the first number */
    numbers[index] = inputFile.nextInt();

    while (numbers[index] != 0) {

        index++;
        numbers[index] = inputFile.nextInt();

    }

    /* Sort the array using the selection sort method; the inner 
       loop finds the smallest unsorted number, and the outer
       loop places it in the right place. */ 

    for (int i = 0; i < index - 1; i++) {

        smallest = numbers[i];
        smallest_index = i;

        for (int j = i + 1; j < index; j++) {

        if (numbers[j] < smallest) { 
                smallest = numbers[j];
                smallest_index = j;
            }
        }

        /* If needed switch numbers[i] and numbers[smallest_index] */

        if (numbers[i] != numbers[smallest_index]) {

            temp = numbers[i];
            numbers[i] = numbers[smallest_index];
            numbers[smallest_index] = temp;
        }
    }

    /* Display the sorted array and also save the result in sorted.txt*/

    for (int i = 0; i < index; i++) {          
    System.out.print (numbers[i] + " ");
        outputFile.print (numbers[i] + " ");
    }

    inputFile.close();
    outputFile.close();

 }
  }

这是Errror获取:

Exception in thread "main" java.util.NoSuchElementException
at java.util.Scanner.throwFor(Unknown Source)
at java.util.Scanner.next(Unknown Source)
at java.util.Scanner.nextInt(Unknown Source)
at java.util.Scanner.nextInt(Unknown Source)
at test.Test.main(Test.java:37)

请任何帮助和解决方案将不胜感激。 提前致谢。

始终通过调用Scanner.hasNext()检查Scanner是否具有下一个元素,而不要跳转到Scanner.Next()

显示该错误是因为扫描仪到达了最后一个元素,并且没有其他要显示的元素了。

首先,由于我猜测每次排序的数字不会相同,因此,我建议使用整数ArrayList。

这是读入方法,并且暗含导入:

    private static ArrayList<Integer> nums;
    public static void readIn() throws FileNotFoundException{
        Scanner sc = new Scanner(new File("file.txt"));
        boolean error = false;
        while(sc.hasNext()&&!error){
            try{
                nums.add(Integer.parseInt(sc.next()));
            }catch(NumberFormatException e){
                e.printStackTrace();
                error = true;
            }
        }
    }

这是最有效的排序代码。

        int[] numbers = (int[]) nums.toArray();
        Arrays.sort(numbers);
        System.out.println(Arrays.toString(numbers)); 

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