@Override
    public void fromData(DataInput din,
        DeserializationContext context) throws IOException, ClassNotFoundException {
      super.fromData(din, context);
      processorId = din.readInt();
      channelState = DataSerializer.readHashMap(din);
      requestingMember = DataSerializer.readObject(din);
      isSingleFlushTo = din.readBoolean();
    }
whether this is a simple request/response two-party flush or (false) a proxied flush
geode-core/src/main/java/org/apache/geode/internal/cache/StateFlushOperation.java