code: public static int getServletSpecLevel() {
          // Always obtain this dynamically.  A cached value does make sense,
          // but there have been problems obtaining the value too early.
  
          int containerSpecLevel = com.ibm.ws.webcontainer.osgi.WebContainer.getServletContainerSpecLevel();
  
          // if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled()) {
          //     Tr.debug(tc, "Servlet container level {0}", Integer.valueOf(containerSpecLevel));
          // }
  
          return containerSpecLevel;
      }
docs: Answer the Servlet specification level.  This is obtained from
  the web container.  See {@link import com.ibm.ws.webcontainer.WebContainer#getServletContainerSpecLevel()}.
  
  @return The Servlet specification level.