Question: I'm trying to learn about how does Java access smart cards, due to a project analysis. I wonder if there is any kind of virtual smart card which I could use to make some tests with Java?

By the way, I've read about Java Card, and looks like it is used to run Java in cards, not to smart card data access using Java, right?

Answer: 
There is a Java Card emulator bundled with the [Java Card Development Kit](http://www.oracle.com/technetwork/java/javacard/downloads/index.html). If you plan on using a real card at some stage, get version 2.2.1 or 2.2.2 as I would not expect any version 3 cards for a while. You will still need an applet to put on the card. A java card does nothing by itself. It isn't until you load a card applet that it will perform any useful function.

One problem with the emulator in the JCDK is that you cannot use javax.smartcardio to access the card and this is the prefered method at the moment for communicating with a card. The other popular alternative, OpenCard Framework, has not been actively maintained in some time.
Javacard use Java only a subset of the Java development You'd better not use Java development environment Because there are some special effects is not support
You can download the plugin or a dedicated development IDE, you can download it from here www.javacos.com related development environment.