Web Components in Action

A.4. Modules

To explore what modules are, we should take a peek at a common feature from other languages: the import. Consider the following class in Java, adapted from a tutorial at www.javatpoint.com/java-swing.

Listing A.16. Example of a Java import

import javax.swing.*;

public class SwingHelloWorld {
     public static void main(String[] args) {
               JFrame f=new JFrame();
               JButton b=new JButton("click");       1
               b.setBounds(130,100,100, 40);         2
               f.add(b);                             3
               f.setSize(400,500);                   4
               f.setLayout(null);
               f.setVisible(true);
    }
}

• 1 Creates instance of button
• 2 Sets x axis, y axis, width, height
• 3 Adds button to UI
• 4 Sets button size

In this Java-based example, we’re programmatically creating a button and placing it in a window. If you don’t know Java, this ...