Read from POS Devices

Question

Hi Experts,

What would be the best design for a Java web based application to read Check or Credit Card from POS Devices which are configured/installed at client machine?

The design which I have decided is:

1. When cashier selects payment mode as 'Check' or 'Credit Card' open a pop-up.
2. From pop-up, I am calling an Applet through JNLP which implements JPOS API to communicate with POS devices at client machine.
3. When cashier swipes Credit Card or inserts check, Applet class read them and send the information back to the pop-up window.
4. Pop up window call the parent window, populate all the required fields and close the pop-up.