I am encountering a problem with file associations in Java (using the terminal command JPackage for building an executable file). The problem is basically the following: when I try to open a file with my application, the file path is not passed to my main method as an argument. Let me share a simplified example of the code below. I am working on IntelliJ Idea on MacOs 12 (Monterey).

This is the (only) class, containing the main method, from which I build an executable .jar file.

import javax.swing.*;
import java.awt.*;

public class Main {

public static void main(String[] args) {

    if (args.length == 0) {

        JFrame frame = new JFrame("Test");
        JLabel label = new JLabel("No arguments");
        frame.setLayout(new BorderLayout());
        frame.add(label, BorderLayout.CENTER);
        frame.setPreferredSize(new Dimension(1000,500));
        frame.pack();
        frame.setVisible(true);

    } else if (args.length == 1) {

        JFrame frame = new JFrame("Test");
        JLabel label = new JLabel(args[0]);
        frame.setLayout(new BorderLayout());
        frame.add(label, BorderLayout.CENTER);
        frame.setPreferredSize(new Dimension(1000,500));
        frame.pack();
        frame.setVisible(true);

    }
}
}

This is the ".properties" file I have written, to set the file association with the ".txt" file type.

mime-type=text/plain
extension=txt
description=Text Source

Finally, here is the terminal command I used to build the executable file for MacOs.

jpackage --type "app-image" --name JavaGuiApp --input /Users/username/Desktop/JavaGuiApp --main-jar JavaGuiApp.jar --file-associations /Users/username/Desktop/JavaGuiApp/FAtxt.properties

I have relied on information found here on JPackage: https://docs.oracle.com/en/java/javase/14/jpackage/packaging-overview.html.

Thank you all in advance for your help!