Aggiungo anche la classe Firefox.java che manca nel primo post:

codice:
package programmi;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.net.URL;

import javax.swing.JOptionPane;
@SuppressWarnings({"static-access"})
public class Firefox {

	private static Tools t = new Tools();
	private static String localFileName = "/var/tmp/Firefox.zip";
	private static String localFinalFolder = "/var/tmp/Firefox";
	
	public Firefox() {
		// TODO Auto-generated constructor stub
	}
	

	public void download() {
		URL url = t.getUrlFromString("http://mattiazago.altervista.org/download/Firefox.zip");
		try {
			t.download(url, localFileName);
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	public void extract() {
		try {
			t.unzip(localFileName);
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
	public void chmod() {
		try {
			t.chmod(localFinalFolder);
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (InterruptedException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}