hi adithya kallu ,
Dont think only servlets contains the package names starts with "javax".From advanced java onwards,we should use the packages starts with "javax.<something>.*"
javax represents java extension.upto AWT we can treat them as "java" packages.
Upto AWT we can't say those r fully platform independent.bcoz all the core applications developed in C or C++ or someother native languages.so core applications have direct communication with OS.so sometimes it doesnot support for platform independence.
where as Advanced applications(we can say from Swings),developed in pure java.so these applications doesnot have direct interaction with the OS.thats y to develop webapplications ,we r using advanced apps.
check the "A Brief History of Swing " in the following link
http://java.sun.com/products/jfc/tsc/articles/getting_started/ regards,
-siva