fileReader和掃描儀

-1

我不明白如何從下面的.txt文件讀取數據。fileReader和掃描儀

static final String DATA_PATH = "DataFile.txt"; 

public static void main(String[] args) { 

    Scanner fileReader = null; 
    try { 

     fileReader = new Scanner(new File(DATA_PATH)); 
     //Print out a trace of the program as it is running 
     System.out.println("Debug: Scanner is open "+fileReader); 
    } catch (FileNotFoundException e) { 
     // If the file is not there, an exception will be thrown and the program flow 
     // will directed here. An error message is displayed and the program stops. 
     System.out.println("The file "+DATA_PATH+" was not found!"); 
     System.out.println("The program terminates now."); 
     System.exit(0); 
    }

來源

2013-06-12 The Mack MAck

真的嗎？你甚至保留練習號碼 – meda

你的冒險精神在哪裏？ :)查看'Scanner'類（web || textbook）的文檔，即使最後輸入一段時間，比如'fileReader.'，也應該打開IntelliSense並給出一些想法。（當你剛剛啓動stackoverflow時，我不會'-1'） –

以下是使用掃描儀的readFile示例。因此，您應該導入三個重要的包：

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

之後，您將創建文件對象以及文件的名稱參數。然後，創建掃描儀對象。最後，你可以使用while循環來逐行閱讀或者任何你想要的東西。

public class ScannerReadFile { 
    public static void main(String[] args) { 
     // 
     // Create an instance of File for data.txt file. 
     // 
     File file = new File("data.txt"); 

     try { 
      // 
      // Create a new Scanner object which will read the data 
      // from the file passed in. To check if there are more 
      // line to read from it we check by calling the 
      // scanner.hasNextLine() method. We then read line one 
      // by one till all line is read. 
      // 
      Scanner scanner = new Scanner(file); 
      while (scanner.hasNextLine()) { 
       String line = scanner.nextLine(); 
       System.out.println(line); 
      } 
     } catch (FileNotFoundException e) { 
      e.printStackTrace(); 
     } 

    }

所以，你可以嘗試從我在這裏提到的代碼開始，練習更多！從網站上的許多教程。

來源

2013-06-12 21:33:55

fileReader和掃描儀

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