Integrating AIR with Peripheral devices

We are planning to build a desktop application using Adobe AIR. The most important aspect of looking at AIR was portability between different devices. There is a requirement that when the AIR application is installed in the Desktop environment it is able to integrate with peripheral devices like signature pads and Credit card devices. How can this be enabled is there a way to integrate AIR with Java?

A quick help regarding this would be highly appreciated since it will help us in making a decision.