使用下载过程连接JProgressBar

我有以下代码。 我不能让它发挥作用。

我必须提到URL是重定向的。 我的意思是url = http://www.thissite.com并重定向到http://www.othersite.com 。 但是我想用初始url来实现它。

  public void download(String address, String localFileName, JProgressBar progress ) { OutputStream out = null; URLConnection conn = null; InputStream in = null; try { URL url = new URL(address); // Open an output stream to the destination file on our local filesystem out = new BufferedOutputStream(new FileOutputStream("/MusicDownloads/"+localFileName)); conn = url.openConnection(); in = conn.getInputStream(); int length = conn.getContentLength(); //find out how long the file is, any good webserver should provide this info int current = 0; progress.setMaximum(length); //we're going to get this many bytes progress.setValue(0); //we've gotten 0 bytes so far // Get the data byte[] buffer = new byte[1024]; int numRead = 0; while ((numRead = in.read(buffer)) != -1) { current=0; out.write(buffer, current, numRead); current += numRead; //we've progressed a little so update current progress.setValue(current); //tell progress how far we are } // Done! Just clean up and get out } catch (Exception exception) { exception.printStackTrace(); } finally { try { if (in != null) { in.close(); } if (out != null) { out.close(); } } catch (IOException ioe) { // Shouldn't happen, maybe add some logging here if you are not // fooling around ;) } } } 

Answer 1

请改用ProgressMonitorInputStream 。