Copy and pest

I need help on how can I write some code using jawin to do the following
task,
I need my code to act as barcode reader driver to take data from java
application to native application on position of cursor.

This is a scenario:
some number will be stored in the javacard smartcard. when card inserted
take this number from the card to java application and then to native
application which currently has fucus.java application will be all the
time running on the back like any service in the system.
I managed to do all task except one of transferring data from java to any
native application.
I want my application to replace barcode reader apart from getting input
from the barcode in put will come from the card.