Java Programming

hi everyone,

first of all let me thank you for your time spend to answer my questions.

well, i am just starting to studying real time system, but during my reading on different documents, i got a little confused over some concepts. perhaps this question are a little dummies.

so, my first question if each system embedded has a Real time operating system such as, Sun,Lynix or if the real time operating system is just used to develop the real time applications. and after the real time application are installed in micro controllers

another doubt is what is the difference betwee real time system adn real time opering system?

and my last question is about Time Trigger Architecture, this architecture needs a RTOS to works, can i used java over this Architecture?

thanks in advaced

have a nice day