docs: public static String readAllBytesAsString(final InputStream inputStream, final long fileSize)
              throws IOException {
          final SimpleEntry<byte[], Integer> ent = readAllBytes(inputStream, fileSize);
          final byte[] buf = ent.getKey();
          final int bufBytesUsed = ent.getValue();
          return new String(buf, 0, bufBytesUsed, StandardCharsets.UTF_8);
      }