Detecting a barcode scanner from a web browser

Question

In the Java EE web application, I need to read the data from a barcode scanner (connected to the user machine - the client side), display the data in a text field and send the code back to the server. I think I understood how to do it.

Can I detect if the scanner is connected / turned on, and if not, display a warning on the web page that the scanner is not connected? (using some activex controls or any other method)

Answer 1

When I did this, I just used the text box to capture input from the scanner. Why do you need to scan a scanner?