docs: public static String getJavadoc(@Nullable final Class<?> clazz) {
      try {
        if (null == clazz) return null;
        @Nullable final File source = com.simiacryptus.util.lang.CodeUtil.findFile(clazz);
        if (null == source) return clazz.getName() + " not found";
        final List<String> lines = IOUtils.readLines(new FileInputStream(source), Charset.forName("UTF-8"));
        final int classDeclarationLine = IntStream.range(0, lines.size())
          .filter(i -> lines.get(i).contains("class " + clazz.getSimpleName())).findFirst().getAsInt();
        final int firstLine = IntStream.rangeClosed(1, classDeclarationLine).map(i -> classDeclarationLine - i)
          .filter(i -> !lines.get(i).matches("\\s*[/\\*@].*")).findFirst().orElse(-1) + 1;
        final String javadoc = lines.subList(firstLine, classDeclarationLine).stream()
          .filter(s -> s.matches("\\s*[/\\*].*"))
          .map(s -> s.replaceFirst("^[ \t]*[/\\*]+", "").trim())
          .filter(x -> !x.isEmpty()).reduce((a, b) -> a + "\n" + b).orElse("");
        return javadoc.replaceAll("<p>", "\n");
      } catch (@javax.annotation.Nonnull final Throwable e) {
        e.printStackTrace();
        return "";
      }
    }