Download file problem

Vaadin 6 / 7 / 8 Framework UI
1

Hello,
I am trying to download a file (say c:/test) from the server to client.
Now it shows the content of the file inside the panel.
But I would like it to show the browser “save/open” window so that the user can choose to save it.
I saw a few posts about it, but did not really find the solution that works.
By the way, it works fine on firefox, but not on explorer.
What am I missing here?
Any help would be appreciated.


			     Panel myPanel = new Panel("my panel");
			     Embedded embedded = new Embedded();
			     FileResource fResource = new FileResource(new File("C:/test"), getApplication());
			     embedded.setSource(fResource); 
			     fResource.getStream().setParameter("Content-Disposition", "attachment; filename=" + "test");
			     //embedded.setMimeType("application/octet-stream");
			     embedded.setType(Embedded.TYPE_BROWSER);
			     myPanel.addComponent(embedded);

Regards,
Momena

2

I actually found the solution right after I posted the question.
I got it from an earlier post, for some reason it did nto work before.
I had to extend the FileResourse as below:



import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;

import com.vaadin.Application;
import com.vaadin.terminal.DownloadStream;
import com.vaadin.terminal.FileResource;
	
	public class FileDownloadResource  extends FileResource{

	public FileDownloadResource(File sourceFile, Application application) {
		super(sourceFile, application);
	}

	public DownloadStream getStream() {
		try {
			final DownloadStream ds = new DownloadStream(new FileInputStream(
					getSourceFile()), getMIMEType(), getFilename());
			ds.setParameter("Content-Disposition", "attachment; filename="
					+ getFilename());
			ds.setCacheTime(getCacheTime());
			return ds;
		} catch (final FileNotFoundException e) {
			//TODO:do something
			return null;
		}
	}
}

My main code looks like this:


FileDownloadResource f = new FileDownloadResource(new File("C:/test"), getApplication());
getWindow().open(f);

Hope this helps someone.

Regards,
Momena

3

Momena,

thanks for providing your solution - it has really helped!

S.

4

Why don’t you use Link instead of Embedded?

5

I have noticed that Google Chrome aggressively caches older copies of files when I use the above FileDownloadResource sample, and then open the file from the main window as follows:

				FileDownloadResource downloadResource = new FileDownloadResource(
						new File(filePathName), getApplication());
				event.getButton().getWindow().open(downloadResource, "_blank");

Is there a way to force it to refresh its cached copy every time? Firefox isn’t as bad about this. I want to make sure that the user does not get the old version of the file whenever I send it to the client this way.

Thanks in advance,
David

6

Does anyone know of a way to force Chrome to update its cache with the new copy of the file each time open() is called? If not, is there another way to accomplish this? Thanks!

7

You can try to set the cacheTime to zero on your FileResource.
Or you could alter the filename, e.g. by adding a counter or date+time.