Create a Jdialog that has an icon just like joptionpane

Question

I have a extended JDialog for a custom dialog because it's a bit complicated and I can't create it with JOptionPane but my issue is I still want to add to the JDialog the same icons that JOptionPane has to keep my dialogs similar in the entire app. These are the Icons provided by java in JOptionPane, but when I create a JDialog it doesn't have an Icon, how can I add one just like JOptionPane without changing into a JOptionPane.

Answer 1

On MacOS, JOptionPane, left to right, top to bottom, Error; Information; Warning; Question

Loaded from UIManager

import java.awt.EventQueue;
import java.awt.GridLayout;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.UIManager;

public class Main {
    public static void main(String[] args) {
        new Main();
    }

    public Main() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                JFrame frame = new JFrame();
                frame.setLayout(new GridLayout(2, 2));
                frame.add(new JLabel(UIManager.getLookAndFeel().getDefaults().getIcon("OptionPane.errorIcon")));
                frame.add(new JLabel(UIManager.getLookAndFeel().getDefaults().getIcon("OptionPane.informationIcon")));
                frame.add(new JLabel(UIManager.getLookAndFeel().getDefaults().getIcon("OptionPane.warningIcon")));
                frame.add(new JLabel(UIManager.getLookAndFeel().getDefaults().getIcon("OptionPane.questionIcon")));
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);

                JOptionPane.showMessageDialog(frame, "Test", "Test", JOptionPane.ERROR_MESSAGE);
                JOptionPane.showMessageDialog(frame, "Test", "Test", JOptionPane.INFORMATION_MESSAGE);
                JOptionPane.showMessageDialog(frame, "Test", "Test", JOptionPane.WARNING_MESSAGE);
                JOptionPane.showMessageDialog(frame, "Test", "Test", JOptionPane.QUESTION_MESSAGE);
            }
        });
    }
}