code: public @Nonnull <T extends ResourceLoader> Optional<T> getLoader(@Nonnull Class<T> resolverType) {
          ArgumentUtils.requireNonNull("resolverType", resolverType);
          return resourceLoaders.stream()
              .filter(rl -> resolverType.isAssignableFrom(rl.getClass()))
              .map(rl -> (T) rl)
              .findFirst();
      }
docs: Searches resource loaders for one that matches or is a subclass of the specified type.
  
  @param resolverType The type of resolver to retrieve
  @param <T>          The type
  @return An optional resource loader