Thread: Need help putting GUI in program!

I have a program that works fine already, I just have to make a GUI for it and have no idea what I am doing lol. I need it to look like the picture I have attached. Can anyone please help! Much appreciated!

import java.io.PrintStream;
import javax.swing.JOptionPane;
 
 
public class DivisibleByTwo
{
    public static void main(String args[])
    {
        int first = Integer.parseInt(JOptionPane.showInputDialog("Enter starting integer."));
        int second = Integer.parseInt(JOptionPane.showInputDialog("Enter ending integer."));
        if(first > second)
        {
            int temp = first;
            first = second;
            second = temp;
        }
        System.out.println((new StringBuilder()).append("The integers divisible by 2 in the range ").append(first).append(" to ").append(second).append(" are:\n").toString());
        for(int l = first; l <= second; l++)
            if(l % 2 == 0)
                System.out.printf("\t\t%5d\n", new Object[] {
                    Integer.valueOf(l)
                });
 
        System.exit(0);
    }
}

I have a basic understanding of creating a GUI but Im having a real hard time turning an already made program into one that has a GUI. Any help please?

I have to put "extends JFrame
implements ActionListener" in right? But do I put it right after "public class DivisibleByTwo" or what? I'm just having trouble incorporating the gui stuff into the code I already have. Thanks