code: public static void bind(FeatureManager featureManager) {
          Object old = managerMap.putIfAbsent(contextClassLoader(), featureManager);
          if (old != null) {
              throw new IllegalStateException(
                  "There is already a FeatureManager associated with the context ClassLoader of the current thread!");
          }
      }
docs: Binds the {@link FeatureManager} to the current context class loader .