code: private String createUri(String uri) {
          try {
              return FileUtil.URI_SEPARATOR_CHAR
                  + FilenameUtils.getPath(uri)
                  + URLEncoder.encode(FilenameUtils.getBaseName(uri), StandardCharsets.UTF_8.name())
                  + config.getOutputExtension();
          } catch (UnsupportedEncodingException e) {
              throw new RuntimeException("Missing UTF-8 encoding??", e); // Won't happen unless JDK is broken.
          }
      }
docs: commons-codec's URLCodec could be used when we add that dependency.