code: public void removeVertxHolder(VertxHolder holder) {
  
      if (this.vertxHolders.contains(holder)) {
        log.log(Level.INFO, "Removing Vertx Holder: " + holder);
        this.vertxHolders.remove(holder);
      } else {
        log.log(Level.SEVERE, "Vertx Holder: " + holder
            + " is out of management.");
      }
    }
docs: Removes the VertxHolder from recorded.
  
  @param holder
  the VertxHolder