code: private void buildParentPath() {
  
          String destFolder = m_destinationDir;
          String inputDir = m_inputDir.replace('\\', '/');
          if (!inputDir.endsWith("/")) {
              inputDir += "/";
          }
          int pos = inputDir.lastIndexOf("/");
          while ((pos > 0) && (destFolder != null)) {
              inputDir = inputDir.substring(0, pos);
              m_parents.put(inputDir + "/", destFolder);
  
              pos = inputDir.lastIndexOf("/", pos - 1);
              destFolder = CmsResource.getParentFolder(destFolder);
          }
      }
docs: Builds a map with all parents of the destination directory to the real file system.<p>
  So links to resources of outside the import folder can be found.<p>