support copy on write updating back to index
@@ -26,4 +26,10 @@ public interface CopyOnWriteIndexPart {
void makeReadOnlyCopy();
+ /**
+ * @param original an instance of ObjectHashSet or OrderedFsSet_sorted
+ * @return true if this cow version is the same as the original.
+ * true means the index has not been updated
+ */
+ boolean isOriginal();
}
