如何使程序在编译时读取任意文件

Question

当我在终端中运行程序时，我需要程序读取任何文本文件，所以如果它看起来像这样：

01.txt中的java TextAnalysis，当我按回车键时。如果我有一个特定的文本文件被扫描仪读取，我知道一切都能正确编译。但是当我尝试用args替换该文件时，它停止了编译，并给出了一个错误：

Exception in thread "main" java.io.FileNotFoundException: in01.txt (No such file or directory)
    at java.io.FileInputStream.open(Native Method)
    at java.io.FileInputStream.<init>(FileInputStream.java:120)
    at java.util.Scanner.<init>(Scanner.java:636)
    at TextAnalysis.main(TextAnalysis.java:17)

来源：

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

public class TextAnalysis {

    public static void main (String [] args) throws IOException {
        String fileName = args[0];
        File file = new File(fileName);
        Scanner fileScanner = new Scanner(file);
        int MAX_WORDS = 10000;
        String[] words = new String[MAX_WORDS];
        int unique = 0;

        System.out.println("TEXT FILE STATISTICS");
        System.out.println("--------------------");
        System.out.println("Length of the longest word: " + longestWord(fileScanner));
        read(words, fileName);
        System.out.println("Number of words in file wordlist: " + wordList(words));
        System.out.println("Number of words in file: " + countWords(fileName));
        System.out.println("Word-frequency statistics");

    }


    public static String longestWord (Scanner s) {
        String longest = "";
        while (s.hasNext()) {
            String word = s.next();
            if (word.length() > longest.length()) {
                longest = word;
            }
        }
        return (longest.length() + " " + "(\"" + longest + "\")");
    }

    public static int countWords (String fileName) throws IOException {
        File file = new File(fileName);
        Scanner fileScanner = new Scanner(file); 
        int count = 0;

            while(fileScanner.hasNext()) {
                String word = fileScanner.next();
                    count++;
            }
        return count;
    }


    public static void read(String[] words, String fileName) throws IOException{
        File file = new File(fileName);
        Scanner s = new Scanner(file);
        while (s.hasNext()) {
        String word = s.next();
        int i;
        for ( i=0; i < words.length && words[i] != null; i++ ) {
            words[i]=words[i].toLowerCase();
            if (words[i].equals(word)) {
                break;
            }
        }
        words[i] = word;
    }
    }

    public static int wordList(String[] words) {
        int count = 0;
        while (words[count] != null) {
            count++;
        }
     return count; 
    }

}

Answer 1

您的文件名中有一个空格，这使得java将您的参数解释为数组{TextAnalysis，in01}。解决此问题的简单方法是将文件名中的空格设置为下划线。

Answer 2

由于您在01.txt中的文件不存在，因此当您尝试使用此文件中的扫描仪时，抛出异常。

确保在TextAnalysis.class所在的目录中有一个名为in01.txt的文件。