Java JFrame inner size-CodePudding

How can I make the inner size 500x500 pixel?

Or should I hardcode the 28px macOS top-bar for windows?

My simple code:

import javax.swing.JFrame;

public class Hello {

    public static void main(String[] args) {
        JFrame frame = new JFrame();

        frame.setSize(500, 500);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setResizable(false);

        frame.setVisible(true);
    }
}

CodePudding user response：

Don't set the JFrame size. Use a JPanel and add that to the JFrame and set the size of the JPanel.

JFrame frame = new JFrame();
JPanel panel = new JPanel();
panel.setPreferredSize(new Dimension(500,500));
frame.add(panel);
frame.pack();
frame.setLocationRelativeTo(null); // centers on screen.
frame.setVisible(true);

If you are extending JPanel it is best to set the size by overridding the following:

@Override
public Dimenison getPreferredSize() {
   return new Dimension(500,500);
}

It is also considered best practice to do most layouts and especially painting inside JPanel(s) and not the JFrame.