How to compile servlets from command prompt?

I'd like to compile a very basic servlet from command prompt, but it is always unsuccessful and the compiler tells me the following:

 error: package javax.servlet does not exist.

I googled for the solution and I found that I need to include the servlet.jar libraries into my PATH.I believe I did.I strongly believe that the location for those libraries in my computer is:

C:\apache-tomcat-7.0.23\lib\servlet-api.jar\ 

and the end (the relevant part) of my PATH is the following:

%JAVA_HOME%\bin;C:\apache-tomcat-7.0.23\lib\servlet-api.jar\

For me, it looks ok, but it is obviously not. Can anyone tell me what could be the problem?