/**

 * @scr.component metatype="no"

 * @scr.service interface="javax.servlet.Servlet"

 * @scr.property name="sling.servlet.paths"

 *               values.0="<my path>"

 * @scr.property name="sling.servlet.methods" values.0="GET" values.1="POST"

 * @scr.property name="sling.servlet.extensions" values.0="json"

 */

public class MyServlet extends SlingAllMethodsServlet {

@Override

    protected void doPost(SlingHttpServletRequest request,

            SlingHttpServletResponse response) throws ServletException,

            IOException {

}

}

See more example here http://sling.apache.org/site/servlets.html

You can also see some example under http://in-the-sling.blogspot.com/2008/09/sling-osgi-track-pt-6-sling-servlets-i.html