docs: protected boolean refreshFromSystem() {
          this.nodeTypesLock.writeLock().lock();
          try {
              // Re-read and re-register all of the node types ...
              SessionCache systemCache = repository.createSystemSession(context, true);
              SystemContent system = new SystemContent(systemCache);
              Collection<NodeTypeDefinition> nodeTypes = system.readAllNodeTypes();
              if (nodeTypes.isEmpty()) return false;
              registerNodeTypes(nodeTypes, false, false, false);
              return true;
          } catch (Throwable e) {
              logger.error(e, JcrI18n.errorRefreshingNodeTypes, repository.name());
              return false;
          } finally {
              this.nodeTypesLock.writeLock().unlock();
          }
      }