如何使用Jfilechooser使用文本文件中的数据

Question

I am trying to use the values from a text file in my program, but first I would like to really understand how to use JFileChooser which I cannot make it work.

The program:

import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;
import javax.swing.JFileChooser;
public class Hw7Problem2 {
    public static void main(String[] args) throws FileNotFoundException {
        JFileChooser student_scores = new JFileChooser();
        int jfcUserOption = student_scores.showOpenDialog(null);
        // To verify it reads
        if (jfcUserOption == JFileChooser.APPROVE_OPTION) {
            File chosenFile = student_scores.getSelectedFile();
            System.out.println("The file you chose was: " + chosenFile.getName());
        }
        Scanner scanner = new Scanner(new File("student_scores.txt"));
        // Print text file on program
        System.out.println(scanner);
    }
}

The error:

The file you chose was: student_scores.txt
Exception in thread "main" java.io.FileNotFoundException: student_scores.txt (The system cannot find the file specified)
    at java.io.FileInputStream.open(Native Method)
    at java.io.FileInputStream.<init>(Unknown Source)
    at java.util.Scanner.<init>(Unknown Source)
    at Hw7Problem2.main(Hw7Problem2.java:21)

Answer 1

You are doing this correctly until you create the scanner. The problem is that you aren't using the result of the JFileChooser. It looks like you put the result in chosenFile . getSelectedFile() will return the file that was chosen, so you just need to create the scanner with it.

If you need to understand more about how the JFileChooser works, you can find the documentation online here .