Java Card

Hi All,

I am newbie in java card field so please excuse questions if they are naive.

Questions:
1. What is ProcessData mehod? what is the use of this method? How to make use this method and in which situation?
2. Can somebody please explain what is the difference between ProcessData method in GP 2.1 and GP 2.2?

I just came across one project which has requirement that target with support for GP2.2 with the extended ProcessData method, personalization shall be performed through a security domain and target without support for GP 2.2 with extended ProcessData method, personalization shall be performed through application.

I have gone through the GP2.1 and GP 2.2 specs. but couldn't find out the difference in ProcessData method for GP 2.1 GP 2.2. Both specs have same little description related to ProcessData method. For GP2.2 why it is called extended ProcessData method? and what is the use of this method?

Based on my initial reading what i understand that ProcessData is one of the entry point of applet apart from common entry points like install, process, select and deselect. so i believe that applet has to implement this method to make use of this functionality. If applet is installed using install for personalization command then all following commands(e.g. Store Data) just after the installation would be delivered by ISD to APSD via ProcessData method. So applet should process apdu in ProcessData method (But still unwrapping of apdu shall be done ProcessData method). This way it is ensured that personalization is done through secure entity.

This is just my understanding. Not sure whether it is correct or not.
Please somebody correct me if i am wrong. These i have understood by reading multiple documents and all documents have little bit of information but not in detail. It would be really helpful for me if somebody can give example by small code using ProcessData method. I couldn't find any example of this on any site.

Any little help will be highly appreciated. And thanks a lot for spending your precious time in reading this quite lengthy thread.

Thanks
Ankit