How do I display an image in Java?

Question

I turns out Java has UI, and some even claim people use it. Here's my little app to play around with it a bit (I shortened it a little)

public class App {
    public static void main(String[] args) {
        MyUI ui = new MyUI();
        ui.display();
    }
}

public class MyUI {
    public void display() {
        new UIBuilder()
                .withPanel(() -> new JPanel() {
                    @Override
                    protected void paintComponent(Graphics g) {
                        Image image = new ImageIcon("statics/img.png").getImage();
                        g.drawImage(image, 3, 4, this);
                    }
                })
                .visualize();
    }

    private static class UIBuilder {
        private final JFrame frame;

        { // initialization and defaults
            frame = new JFrame();
            frame.setSize(300, 300);
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        }

        private UIBuilder withPanel(Supplier<JPanel> panelSupplier) {
            JPanel panel = panelSupplier.get();
            frame.getContentPane().add(panel);
            return this;
        }

        private UIBuilder withFrameSize(int width, int height) {
            frame.setSize(width, height);
            return this;
        }

        private UIBuilder withDefaultCloseOperation(int windowConstant) {
            frame.setDefaultCloseOperation(windowConstant);
            return this;
        }

        private void visualize() {
            frame.setVisible(true);
        }
    }
}

The problem: no image is displayed. It's a 1200x800 PNG-file. In my attempt to troubleshoot, I changed the panel code to this

        Image image = null;
        try {
            image = ImageIO.read(new File("statics/img.png"));
        } catch (IOException e) {
            e.printStackTrace();
        }

        if (image != null) {
            g.drawImage(image, 3, 4, this); // I also tried g.drawImage(image, 3, 4, 200, 150, this);
        } else {
            System.out.println("Error loading image.");
        }

Result:

javax.imageio.IIOException: Can't read input file!
    at java.desktop/javax.imageio.ImageIO.read(ImageIO.java:1310)
    at org.example.demos.ui.MyUI$1.paintComponent(MyUI.java:32)

What is causing the issue? The directory and the file name are ok

UPD: For some reason, specifying the path from the content root helped. If it's in the statics folder, src/main/java/org/example/demos/ui/statics/img.png does the job

new ImageIcon("src/main/java/org/example/demos/ui/statics/img.png").getImage()

I expected relative paths to be resolved relative to the main class directory. It was typically the case before, in other projects. I don't know why it's different here