class DelegatingDataLoaderRegistry extends DataLoaderRegistry {
        private final List<DataLoaderRegistry> registries;

        public DelegatingDataLoaderRegistry(List<DataLoaderRegistry> registries) {
            this.registries = registries;
        }

        @Override
        public List<DataLoader<?, ?>> getDataLoaders() {
            List<DataLoader<?, ?>> loaders = new ArrayList<>(super.getDataLoaders());
            registries.forEach( dlr -> loaders.addAll(dlr.getDataLoaders()));
            return loaders;
        }

        @Override
        public Map<String, DataLoader<?, ?>> getDataLoadersMap() {
            Map<String, DataLoader<?, ?>> loaders = new LinkedHashMap<>(super.getDataLoadersMap());
            registries.forEach( dlr -> loaders.putAll(dlr.getDataLoadersMap()));
            return loaders;
        }

        @Override
        public <K, V> DataLoader<K, V> getDataLoader(String key) {
            DataLoader<K, V> dataLoader = super.getDataLoader(key);
            if (dataLoader == null) {
                for (DataLoaderRegistry registry : registries) {
                    dataLoader = registry.getDataLoader(key);
                    if (dataLoader != null) {
                        return dataLoader;
                    }
                }
            }
            return null;
        }

        @Override
        public Set<String> getKeys() {
            return getDataLoadersMap().keySet();
        }

        @Override
        public void dispatchAll() {
            super.dispatchAll();
            for (DataLoaderRegistry registry : registries) {
                registry.dispatchAll();
            }
        }

        @Override
        public int dispatchAllWithCount() {
            int count = super.dispatchAllWithCount();
            for (DataLoaderRegistry registry : registries) {
                count += registry.dispatchAllWithCount();
            }
            return count;
        }

        @Override
        public int dispatchDepth() {
            int count = super.dispatchDepth();
            for (DataLoaderRegistry registry : registries) {
                count += registry.dispatchDepth();
            }
            return count;
        }

    }