R – servlet compiling error

I came up with a slightly different solution. It's a bit hack-ish, but here is the mapping:

<servlet-mapping>   
    <servlet-name>default</servlet-name>
    <url-pattern>*.html</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>default</servlet-name>
    <url-pattern>*.jpg</url-pattern>
</servlet-mapping>
<servlet-mapping>
 <servlet-name>default</servlet-name>
    <url-pattern>*.png</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>default</servlet-name>
    <url-pattern>*.css</url-pattern>
</servlet-mapping>
<servlet-mapping>
    <servlet-name>default</servlet-name>
    <url-pattern>*.js</url-pattern>
</servlet-mapping>

<servlet-mapping>
    <servlet-name>myAppServlet</servlet-name>
    <url-pattern>/</url-pattern>
</servlet-mapping>

This basically just maps all content files by extension to the default servlet, and everything else to "myAppServlet".

It works in both Jetty and Tomcat.

How do I compile and run a servlet from the Command Prompt?

For the first part of the question, you'll need to put the servlet API on you classpath:

javac -cp $TOMCAT_HOME/lib/servlet-api.jar *.java

For the second part, what you are trying to achieve is a bit unclear. A Servlet is intended to be packaged in a WAR and deployed in a Servlet container (like Tomcat). A Servlet doesn't have a main() method, it's not intended to be run on the command line.

Actually, you should start with a good tutorial like Introduction to Developing Web Applications and get some IDE support. NetBeans is not my favorite IDE but they have very good educational material and, in your case, I think it would be a good starting point.