package designpatterns.decorator.java;import java.awt.event.*;import java.io.*;import javax.swing.*;import worker.SwingWorker;public class Driver extends JPanel {	private JTextField name = new JTextField("Enter a File name");	private JButton readButton;	private JLabel bytesReadLabel = new JLabel("Nothing read");	private int bytesRead;		public Driver(){		readButton = buildReadButton();				add(name);		add(readButton);		add(bytesReadLabel);	}				private JButton buildReadButton() {		JButton readButton = new JButton("Go!");		readButton.addActionListener(new ActionListener(){			public void actionPerformed(java.awt.event.ActionEvent ae){				readFile();			}		});		return readButton;	}	protected void readFile() {		//SwingWorker necessary so that a time-consuming file-read		//can happen in its own thread and allow GUI updates to keep		//happening. This can be automated in AspectJ		//with the worker-object pattern.		SwingWorker worker = new SwingWorker(){			public Object construct(){				actuallyReadFile();				return null;			}		};		worker.start();	}	private void actuallyReadFile() {		try {			InputStream in = createInputStream();			byte[] b =new byte[1000];			while (in.read(b) != -1) {				//do whatever here				bytesRead+=1000;			}			bytesReadLabel.setText("Read " +  (bytesRead/1000) + "k");			bytesRead = 0;			in.close();		} catch (Exception e) {			throw new RuntimeException(e);		}	}	private InputStream createInputStream() throws FileNotFoundException {		InputStream stream = new FileInputStream(name.getText());		stream = new BufferedInputStream(stream);				//_this_ is a JPanel GUI component		stream = new ProgressMonitorInputStream(				 this, "This is gonna take a while", stream);		return stream;	}	public static void main(String[] args)	{		JFrame frame = new JFrame("Decorator Example");		frame.addWindowListener(new WindowAdapter() {			public void windowClosing(WindowEvent e) {System.exit(0);}		});  				frame.getContentPane().add(new Driver());				frame.pack();		frame.setVisible(true);	}}