Barra de progresso para File Upload

import java.io.*;
import java.awt.*;
import javax.swing.*;

public class ProgressMonitorInputExample {
    
    public ProgressMonitorInputExample(String filename) {
        ProgressMonitorInputStream monitor;
        try {
            monitor = new ProgressMonitorInputStream(
                    null, "Loading "+filename, 
                    new FileInputStream(filename));
            
            while (monitor.available() > 0) {
                byte[] data = new byte[1024];
                monitor.read(data);
                System.out.write(data);
            }
        } catch (FileNotFoundException e) {
            JOptionPane.showMessageDialog(null, 
                    "Unable to find file: "
                    + filename, "Error", JOptionPane.ERROR_MESSAGE);
            
        } catch (IOException e) {;}
    }
    
    public static void main(String args[]) {
        new ProgressMonitorInputExample(args[0]);
    }
}