public void setOldValue(EntryEventImpl event) {
    if (event.hasOldValue()) {
      hasOldValue = true;
      CachedDeserializable cd = (CachedDeserializable) event.getSerializedOldValue();
      if (cd != null) {
        if (!cd.isSerialized()) {
          // it is a byte[]
          oldValueIsSerialized = false;
          setOldValBytes((byte[]) cd.getDeserializedForReading());
        } else {
          oldValueIsSerialized = true;
          Object o = cd.getValue();
          if (o instanceof byte[]) {
            setOldValBytes((byte[]) o);
          } else {
            // Defer serialization until toData is called.
            setOldValObj(o);
          }
        }
      } else {
        Object old = event.getRawOldValue();
        if (old instanceof byte[]) {
          oldValueIsSerialized = false;
          setOldValBytes((byte[]) old);
        } else {
          oldValueIsSerialized = true;
          setOldValObj(AbstractRegion.handleNotAvailable(old));
        }
      }
    }
  }
Set the old value for this message, only used if there are cqs registered on one of the bridge
servers.

@param event underlying event.
@since GemFire 5.5
geode-core/src/main/java/org/apache/geode/internal/cache/tx/RemoteDestroyMessage.java