HOW does it work?

the easiest way is to create a standard frame with the preset class JOptionPane.

1. create a standard main-program setup
   package JFrame;
   
   public class printFrame {
   
   	void start () {
   	}
   	
   	public static void main(String[] args) {
   		new printFrame().start();
   	}
   	
   }

   a small example as that does not necessarily need a constructor

2. import JOptionPane
   import javax.swing.JOptionPane;

3. add: JOptionPane.showMessageDialog(frame, message, title, messageOption);
   in the start method

   void start () {
   	JOptionPane.showMessageDialog(frame, message, title, messageOption);
   }

4. create the value for the variables | frame can be set null for default. An example is shown below:
   String title = "OUTPUT WINDOW";
   String message = "HELLOWORLD";
   JFrame frame = null;
   int messageOption = JOptionPane.INFORMATION_MESSAGE;

In this example we import the preset class JFrame, to work with a JFrame, frame.

Program

package JFrame;

import javax.swing.JFrame;
import javax.swing.JOptionPane;

public class printFrame {
	String title = "OUTPUT WINDOW";
	String message = "HELLOWORLD";
	JFrame frame = null;
	int messageOption = JOptionPane.INFORMATION_MESSAGE;
	

	void start () {
		JOptionPane.showMessageDialog(frame, message, title, messageOption);
		
	}
	
	public static void main(String[] args) {
		new printFrame().start();
	}
	
}

OUTPUT

Synonym: GUI OUtPUT | JOptionPane OUTPUT | SWING OUTPUT | DISPLay output