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scanner class in java

Hey I'm trying to compile 开发者_JAVA百科the following piece of code to basically read stuff from a file but it refuses to work. it gives me an java.io.FILENOTFOUNDEXCEPTION error at line4. help would be appreciated.

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


 public class test{
    public static void main(String args[]) {
    File fin = new File ("matrix1.txt");
    Scanner scanner = new Scanner(fin);
       while (scanner.hasNextLine()){
       String line = scanner.nextLine();
       System.out.println(line);
       }
    }
 }


Try putting the absolute path to the file, like

c:\\java\\matrix1.txt or /home/user/java/matrix1.txt

=== OOPS

You need to catch the Exception that's being thrown. Here's a couple options:

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

public class test{
    public static void main(String args[]) throws FileNotFoundException {
    File fin = new File ("matrix1.txt");
    Scanner scanner = new Scanner(fin);
       while (scanner.hasNextLine()){
       String line = scanner.nextLine();
       System.out.println(line);
       }
    }
 }

OR

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


 public class test{
    public static void main(String args[]) {
       File fin = new File ("matrix1.txt");

       Scanner sc = null;
       try {
           scanner = new Scanner(fin);
       }
       catch(FileNotFoundException e) {
          System.out.println("File does not exist...");
          return;
       }
       while (scanner.hasNextLine()){
       String line = scanner.nextLine();
       System.out.println(line);
       }
    }
 }


Make sure matrix1.txt is in your src folder if you're using Eclipse.


If you're using an IDE such as Netbeans/Eclipse, you need to put the file to be read in the project folder. This is usually 1 level above the src folder.

A good alternative in case you can't find the folder is to try and create a file. That way, you know where the file was created and you can place the file you want to read in that same folder.

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