code: public ServletHolder addServlet(String name,
                                      String pathSpec,
                                      String servletClass,
                                      String forcedPath)
      {
          ServletHolder holder = getServletHolder(name);
          if (holder==null)
              holder = newServletHolder(name,servletClass,forcedPath);
          mapPathToServlet(pathSpec,name);
          if (isStarted() && !holder.isStarted())
          {
              try{holder.start();}
              catch(Exception e){log.warn(LogSupport.EXCEPTION,e);}
          }
          return holder;
      }
docs: Add a servlet.
  @param name The servlet name.
  @param pathSpec A path specification to map this servlet to.
  @param servletClass The class name of the servlet.
  @param forcedPath If non null, the request attribute
  javax.servlet.include.servlet_path will be set to this path before
  service is called.
  @return The ServletHolder for the servlet.