private static BigInteger readBigInteger(DataInput in) throws IOException {
    InternalDataSerializer.checkIn(in);
    BigInteger result = new BigInteger(Objects.requireNonNull(DataSerializer.readByteArray(in)));
    if (logger.isTraceEnabled(LogMarker.SERIALIZER_VERBOSE)) {
      logger.trace(LogMarker.SERIALIZER_VERBOSE, "Read BigInteger: {}", result);
    }
    return result;
  }
Reads a {@code TimeUnit} from a {@code DataInput}.

@throws IOException A problem occurs while writing to {@code out}
geode-core/src/main/java/org/apache/geode/internal/InternalDataSerializer.java