apollo-biz/src/main/java/com/ctrip/framework/apollo/biz/service/AppNamespaceService.java/AppNamespaceService/findPublicNamespacesByNames
class AppNamespaceService:  public List<AppNamespace> findPublicNamespacesByNames(Set<String> namespaceNames) {
    if (namespaceNames == null || namespaceNames.isEmpty()) {
      return Collections.emptyList();
    }

    return appNamespaceRepository.findByNameInAndIsPublicTrue(namespaceNames);
  }