code: @CheckForNull
      public String extractJvmRoute( @Nonnull final String sessionId ) {
          final int idxDot = sessionId.indexOf( '.' );
          return idxDot < 0 ? null : sessionId.substring( idxDot + 1 );
      }
docs: Extract the jvm route from the given session id if existing.
  
  @param sessionId
  the session id possibly including the memcached id and eventually the
  jvmRoute.
  @return the jvm route or null if the session id didn't contain any.