The Quintessential Swing User Interface
This example creates and shows a frame with a button. 

 
 import java.awt.*;
 import javax.swing.*;
     
 public class BasicUI {
     public static void main(String[] args) {
         JButton button = 
           new JButton("Label");
         JFrame frame = new JFrame();
     
         // Add button to the frame.
         frame.getContentPane().add(
           button, BorderLayout.CENTER);
    
         // Set initial size.
         frame.setSize(300,
            300);
     
         // Show the frame.
         frame.setVisible(true);
     }
 }