first:
you need some tools to convert and load applets on card.you can find this tools
in company website that produced your card (and reader).
applet conversion is like this:
java-->class-->cap(jar of caps)
second:
I think that you want to recognize javacard javacarddevelopementkit version if
you want to develop an applet.so you can find it in card specification (card
manual,readme,... or company website).