JOptionPane : Message Dialog in Java Swing

Program to demonstrate working of JOptionPane's Message Dialog in Java Swing

import javax.swing.ImageIcon;
import javax.swing.JOptionPane;

public class MessageDialogDemo {

 public static void main(String[] args) {

  JOptionPane.showMessageDialog(null, "Hello World !!!"); 
  
  JOptionPane.showMessageDialog(null, "Hello World !!!", "Welcome",
    JOptionPane.PLAIN_MESSAGE);
  
  JOptionPane.showMessageDialog(null, "Hello World !!!", "Welcome",
    JOptionPane.INFORMATION_MESSAGE);
  
  JOptionPane.showMessageDialog(null, "Hello World !!!", "Welcome",
    JOptionPane.WARNING_MESSAGE);
  
  JOptionPane.showMessageDialog(null, "Hello World !!!", "Welcome",
    JOptionPane.QUESTION_MESSAGE);
  
  JOptionPane.showMessageDialog(null, "Hello World !!!", "Welcome",
    JOptionPane.ERROR_MESSAGE);
  ImageIcon icon = new ImageIcon("CD.png");
  
  JOptionPane.showMessageDialog(null, "Hello World !!!", "Welcome", 
    JOptionPane.INFORMATION_MESSAGE, icon);  

 }

}

Output of the program :

Watch the Youtube video below for better understanding ...