@Override
    protected Object[] getVariants(@NotNull PsiReferenceBase reference) {
      Charset[] charsets = CharsetToolkit.getAvailableCharsets();

      LookupElement[] res = new LookupElement[charsets.length];
      for (int i = 0; i < charsets.length; i++) {
        res[i] = LookupElementBuilder.create(charsets[i].name()).withCaseSensitivity(false);
      }

      return res;
    }
@Override
    protected Object[] getVariants(@NotNull PsiReferenceBase reference)