Apache Commons IO Download With Progress Bar

package com.cjburkey.mods.bayc;

import java.awt.Dimension;
import java.awt.FlowLayout;
import java.io.File;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection;
import javax.swing.JFrame;
import javax.swing.JProgressBar;
import javax.swing.ProgressMonitorInputStream;
import org.apache.commons.io.FileUtils;

public class Net {

    public static final void download(final String url, final File dest) {
        try {

            final JFrame frame = new JFrame();
            final JProgressBar bar = new JProgressBar(0, 100);

            bar.setStringPainted(true);
            bar.setString("Loading...");
            bar.setPreferredSize(new Dimension(512, (int) bar.getPreferredSize().getHeight()));

            frame.setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
            frame.setLayout(new FlowLayout());
            frame.add(bar);
            frame.pack();
            frame.setResizable(false);
            frame.setLocationRelativeTo(null);
            frame.setVisible(true);

            new Thread(new Runnable() {
                public void run() {
                    URLConnection con = null;

                    try {
                        con = new URL(url).openConnection();
                    } catch (Exception e) {
                        Core.error(e);
                    }

                    long total = con.getContentLength(), prog = 0;
                    float percent = 0;

                    while(percent < 99) {
                        prog = dest.length();
                        percent = ((float) prog / (float) total) * 100;

                        bar.setValue((int) percent);
                        bar.setString(String.format("%.2f", percent) + "%");

                        frame.setTitle(dest.getName().replaceAll(".jar", ""));
                        frame.requestFocus();
                        frame.setLocationRelativeTo(null);

                        try {
                            Thread.sleep(250);
                        } catch (Exception e) {
                            Core.error(e);
                        }
                    }
                }
            }).start();

            Core.downloaded = true;

            InputStream stream = new URL(url).openStream();
            ProgressMonitorInputStream pmis = new ProgressMonitorInputStream(null, "Downloading...", stream);
            FileUtils.copyInputStreamToFile(pmis, dest);

            frame.dispose();
        } catch(Exception e) {
            Core.error(e);
        }
    }

}