Java™ Application Development on Linux - Dator

342Chapter 16Getting in the Swing of Things: Designing a GUI for BudgetPro16.2A SIMPLE SWING PROGRAMLet’s take a look at a very simple (in its function, not in its composition)Swing program—a simple “Hello, world” that will appear in a window(Example 16.1).Example 16.1 A simple Swing applicationimport java.awt.*;import javax.swing.*;public classhw{public static voidmain(String[] args){//Create the top-level containerJFrame frame = new JFrame();JLabel hi = new JLabel("Hello, world.");frame.getContentPane().add(hi, BorderLayout.CENTER);frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);frame.pack(); // kicks the UI into actionframe.setVisible(true);} // main} // class hwNow compile this program and run it from the command line like this:$ javac hw.java$ java hwYou should then see a small window appear, looking as in Figure 16.1.Figure 16.1 “Hello, world” in a Swing window