Java n viruses

Hi I also kinda new to Java I'm using it to implement my university project.
There was an instance where my comrades started bragging about their programming skills and of course I couldn't be left out with my little Java but now had to make it a mountain (by the way I'm ex-Visual Basic). The issues went down the virus lines n some talked of what their viruses would do, since I hadn't thot along those lines in java I had to sum it with a win, I thus pointed out that their viruses are limited to Windows as their codes are platform independent but the ones we write in java can basically attack any OS. Now this was agreed because of platform independence of java which they hear of but know nothing about.
Ok as one who knew about platform dependence I thot : java progs need JRE so can I really write a virus in java to attack any OS.
Pls Somebody to answer this and shed more insight.

No....
Java was carefully designed.

Creating a virus = Business(Anti Virus)...

Are you planning to create your own Anti-Virus?

I'm not really willing to go down that load but if I knew smt bout it it wouldn't hurt.
Does that mean Java prg can't act as viruses coz of the whole JRE issue

I never created a virus before, but

Java can destroy the system.... If and only if it was invoked....
(Not virus/ maybe bacteria)