With the upload component, you can access the local file system of the client to select any files and upload them on the server.

Variant 1: Property "Immediate = false" 

The component consists of two buttons: the first opens the local file manager and enables the selection of a file, whereas the second starts the upload activity.
The name of the selected file will be displayed between the two buttons. Important: The upload does not start until the "Upload" button is pressed.

Variant 2: Property "Immediate = true" 

The component consists of only one button. This triggers the filechooser and the upload immediately. Important: The upload is triggered immediately after the file selection.


The upload component requires a "receiver" which receives the file on the server side and processes it. The receiver can be initialized in the constructor or in the INIT-event of the respective window. See code example below.

Important properties:
Important events:
Data binding:

public class MainView extends XdevView {

	File file;

	public MainView() {

		final Receiver receiver = new Receiver() {

		    public OutputStream receiveUpload(final String filename, final String mimeType) {
		        // Create upload stream to write to

		        FileOutputStream fos = null;
		        try {

		            // Get path to servlet's temp directory
		            final File temporaryDirectory = (File) VaadinServlet.getCurrent().getServletContext().getAttribute(ServletContext.TEMPDIR);

		            // Concatenate temporaryDirectory with filename and open the file for writing.
		            MainView.this.file = new File(temporaryDirectory, filename);

		            // Create the output stream
		            fos = new FileOutputStream(MainView.this.file);

		        } catch (final java.io.FileNotFoundException e) {
		            Notification.show("Could not open file", Type.ERROR_MESSAGE);
		            return null;
		        return fos;
		// Set Receiver for upload component

All XdevUpload Methods