code: public void importAliases(HttpServletRequest request, HttpServletResponse response) throws Exception {
  
          FileItemFactory factory = new DiskFileItemFactory();
          ServletFileUpload upload = new ServletFileUpload(factory);
          @SuppressWarnings("unchecked")
          List<FileItem> items = upload.parseRequest(request);
          byte[] data = null;
          String siteRoot = null;
          String separator = ",";
          for (FileItem fileItem : items) {
              String name = fileItem.getFieldName();
              if (PARAM_IMPORTFILE.equals(name)) {
                  data = fileItem.get();
              } else if (PARAM_SITEROOT.equals(name)) {
                  siteRoot = new String(fileItem.get(), request.getCharacterEncoding());
              } else if (PARAM_SEPARATOR.equals(name)) {
                  separator = new String(fileItem.get(), request.getCharacterEncoding());
              }
          }
          List<CmsAliasImportResult> result = new ArrayList<CmsAliasImportResult>();
          if ((siteRoot != null) && (data != null)) {
              result = OpenCms.getAliasManager().importAliases(m_cms, data, siteRoot, separator);
          }
          String key = CmsVfsSitemapService.addAliasImportResult(result);
          // only respond with a key, then the client can get the data for the key via GWT-RPC
          response.getWriter().print(key);
      }
docs: Imports uploaded aliases from a request.<p>
  
  @param request the request containing the uploaded aliases
  @param response the response
  @throws Exception if something goes wrong