Why java? what java internal architecture?

Hi all,

Last 3 month i am working with java card technology for smart card personalization.

In that java card technology we can program using the byte array,short only. Because of very memory constrain in smartcard.

I am very keen interest in writing this kind of program.

when i was working i had lot of doubt in my mind like.

Java System level doubt:

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1. what is byte datatype?
2. why we are using byte datatype?
3. is there any purpose like integer/float datatype?
4. why standard edition allocated 2 byte for char data type?
5. how java supporting multi language what formula behind this operation?
6. what is JVM?
7. What is JDK?
8. what is JRE?
9. what is the main difference between JDK and JRE?
10. why java has different type of memory allocation?
11. where object are persist in standard java for later use?
12. what is the default directory structure of the java after installation?
13. why java specification?
14. why Stack memory?
15. why string pool?
16. what is the need of Heap memory?
17. what is the minimum size of Heap memory allocated initially?

Java Programming level doubt:

1. why java uses public static void main(String arg[]) method as entry point?
2. why java interface?where it will fit in real time operation?where JAVA API used Interface?
3. why abstract class?where it will fit in real time operation?

I will post the answer for the above all question as individual article with sample program than only we can understand.

I hope i will explain all the concept with in March 30th.

If any one walk across my blog give me teaspoon of energy(feedback/comments) for next article.

Regards,

MariMuthu

Passion for Software Application/Product development.