import javax.swing.*; //This is necessary to use the JFrame class


/** Drawing a window. Not really Object-Oriented Programming, but to show you how to draw a window and
    set its title and size.
*/
class SimpleFrameTest {
    
    /** Constants for the window size. */
    public static final int WIDTH=300;   
    public static final int HEIGHT=200;
    
    public static void main(String[] args){
        JFrame frame = new JFrame();       //create an Object of class JFrame, this is mainly a window.
        frame.setSize(WIDTH,HEIGHT);
        frame.setTitle("Hello World !");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);  //What to do when the window is closed. EXIT_ON_CLOSE is a static final field (a static constant) of the JFrame class.
        frame.show();     //Now that it is ready you need to show the window.
    }
}