I am trying to compile servlets and javac just won't recognize the http keyworkds

import java.io.*;
import javax.servlet.*; //error here
import javax.servlet.http.*; //error here
public class HelloWorld extends HttpServlet { //error here
public void doGet(HttpServletRequest request, //error here
HttpServletResponse response) //error here
throws ServletException, IOException { //error here
PrintWriter out = response.getWriter();
out.println("Hello World");
}
}

already have tomcat on my ubuntu system. in the etc/environment file, the classpath is already set and it is

CLASSPATH=.:$TOMCAT_HOME/lib/servlet-api.jar:$TOMCAT_HOME/lib/jsp-api.jar:$TOMCAT_HOME/lib

any help would be apprecicated, stuck with this one for 2 days already and I am very much clueless :confused:

:D