The Key Interface Class:

Because this is a hardware implementation, the encoding associated with keys that are SENSITIVE have no meaning. These keys cannot be transported to another system for use. All keys of this provider have an associated PKCS11Object, which is the hardware represention of the key. To get these keys, call:
public PKCS11Object getObject()

All key classes of this provider implement PKCS11Key, which defines the basic parts of a key.