code: public List<String> getLockedResources(CmsRequestContext context, CmsResource resource, CmsLockFilter filter)
      throws CmsException {
  
          CmsDbContext dbc = m_dbContextFactory.getDbContext(context);
          List<String> result = null;
          try {
              checkOfflineProject(dbc);
              checkPermissions(dbc, resource, CmsPermissionSet.ACCESS_READ, false, CmsResourceFilter.ALL);
              result = m_driverManager.getLockedResources(dbc, resource, filter);
          } catch (Exception e) {
              dbc.report(
                  null,
                  Messages.get().container(Messages.ERR_COUNT_LOCKED_RESOURCES_FOLDER_1, context.getSitePath(resource)),
                  e);
          } finally {
              dbc.clear();
          }
          return result;
      }
docs: Returns all locked resources in a given folder.<p>
  
  @param context the current request context
  @param resource the folder to search in
  @param filter the lock filter
  
  @return a list of locked resource paths (relative to current site)
  
  @throws CmsException if something goes wrong