How to get the progress when copying a file using BufferedOutputStream & SwingWorker

Question

I am copying a file from my computer to an external device, such as an SD card, and I would like to get the progress during the file copying process. I am using SwingWorker so that I can have multiple files copying at the same time. I am not sure how to get the current progress and send it to the SwingWorker publish() method. Here is my code to copy the file:

FileInputStream finStream = new FileInputStream(sourceFile);
FileOutputStream foutStream = new FileOutputStream(destFile);

/*
 * Adapted from http://www.java2s.com/Code/Java/File-Input Output/UseBufferedInputStreamandBufferedOutputStreamtocopybytearray.html
 */
BufferedInputStream bufIS = new BufferedInputStream(finStream);     
BufferedOutputStream bufOS = new BufferedOutputStream(foutStream);

byte[] byteBuff = new byte[32 * 1024];
int len;
while ((len = bufIS.read(byteBuff)) > 0){
    bufOS.write(byteBuff, 0, len);
    publish(/*What do I put here?*/);
}

bufIS.close();
bufOS.close();

Answer 1

Swingworker has already a "progress feature", use it instead of publish/process

long size = file.length();

int count = 0;
int progress;
while ((len = bufIS.read(byteBuff)) > 0) {
  ...
  count += len;
  if (size > 0L) {
    progress = (int) ((count * 100) / size);
    setProgress(progress);
  }
}

Then you can use worker.getProgress() in EDT or a PropertyChangeListener with a progressBar or whatever

E.g:

public class MyWorker extends SwingWorker<Void, Void> implements PropertyChangeListener {

    public MyWorker() {
      addPropertyChangeListener(this);
    }

    ....
    /* Your code */
    ....

   @Override
   public void propertyChange(PropertyChangeEvent evt) {

      if ("progress".equals(evt.getPropertyName())) {
        myProgressBar.setValue((Integer) evt.getNewValue());
      }
   }

}

Or

MyWorker worker = new MyWorker();
worker.addPropertyChangeListener(new PropertyChangeListener() {

    @Override
    public void propertyChange(PropertyChangeEvent evt) {
        if ("progress".equals(evt.getPropertyName())) {
            myProgressBar.setValue((Integer) evt.getNewValue());
        }
    }
}

If you prefer publish/process then public class MyWorker extends SwingWorker<Void, Integer> and you will be able to call publish with an Integer