code: public Set<CmsPublishedResource> getRelatedResources(CmsObject cms, CmsPublishedResource publishedResource)
      throws CmsException {
  
          if (match(publishedResource.getRootPath())) {
              return getExportResources(cms);
          }
          return null;
      }
docs: Returns a set of <code>{@link CmsPublishedResource}</code> objects specified by the
  <code>&lt;export-resources&gt;</code> node of this rule, if the publishedResource
  matches a modified Resource regular expression.<p>
  
  @param cms the cms context
  @param publishedResource a published resource to test
  
  @return a set of matching resources, or <code>null</code> if resource does not match
  
  @throws CmsException if something goes wrong