Displaying an Image

import javax.swing.*;

public class MessageTest
{
   public static void main(String[] args)
   {
      JOptionPane.showMessageDialog(null, "Hello, World!");
      System.exit(0);
   }
}

Results

IconTest.java

import javax.swing.*;

public class IconTest
{
   public static void main(String[] args)
   {
      JOptionPane.showMessageDialog(
         null, 
         "Hello, World!",
         "Message",
         JOptionPane.INFORMATION_MESSAGE,
         new ImageIcon("globe.gif"));
      System.exit(0);
   }
}

Results