public static void serializeNullableString(ByteBuf outputBuf, String value) {
    if (value == null) {
      outputBuf.writeInt(0);
    } else {
      serializeString(outputBuf, value, Charset.defaultCharset());
    }
  }
Serializes a nullable string into {@link ByteBuf} using the default charset.

@param outputBuf The output buffer to serialize the value to
@param value The value to serialize
ambry-utils/src/main/java/com/github/ambry/utils/Utils.java