读取文件从电脑

Question

现在我有这样的错误：在线程 “主要” java.lang.ArrayIndexOutOfBoundsException

例外：4 在Lotto1.main（Lotto1.java:37）

37号线：arr [count] [0] = s.next（）+“”+ s.next（）;

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

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

     File f = new File("D:\\Filipe\\Project Final\\src\\database_lotto.txt"); 
     Scanner s; 
     try { 
      s = new Scanner(f); 

      BufferedReader reader = new BufferedReader(new FileReader(f)); 
      int lines = 0; 
      while (reader.readLine() != null) { 
       lines++; 
      } 
      reader.close(); 

      arr = new String[lines][3]; 

      int count = 0; 
      //while theres still another line 
      while (s.hasNextLine()){ 
       arr[count][0] = s.next() + ""+ s.next(); 
       arr[count][1] = s.next(); 
       arr[count][2] = s.next(); 
       count++;     
      } 
     } catch (FileNotFoundException ex) { 
      System.out.println("File does not exist"); 
     } 

Answer 1

你没有把正确的路径进入的FileReader只进文件F，你可以通过˚F到的FileReader而不是重复的路径：

File f = new File("D:\\database_lotto.txt"); 
[...] 
BufferedReader reader = new BufferedReader(new FileReader(f));