- Collection<DataNode> queryDataNodes(@NonNull String dataspaceName, @NonNull String anchorName,
- @NonNull String cpsPath, @NonNull FetchDescendantsOption fetchDescendantsOption);
+ List<DataNode> queryDataNodes(String dataspaceName, String anchorName,
+ String cpsPath, FetchDescendantsOption fetchDescendantsOption);
+
+ /**
+ * Starts a session which allows use of locks and batch interaction with the persistence service.
+ *
+ * @return Session ID string
+ */
+ String startSession();
+
+ /**
+ * Close session.
+ *
+ * @param sessionId session ID
+ */
+ void closeSession(String sessionId);
+
+ /**
+ * Lock anchor.
+ * To release locks(s), the session holding the lock(s) must be closed.
+ *
+ * @param sessionID session ID
+ * @param dataspaceName dataspace name
+ * @param anchorName anchor name
+ * @param timeoutInMilliseconds lock attempt timeout in milliseconds
+ */
+ void lockAnchor(String sessionID, String dataspaceName, String anchorName, Long timeoutInMilliseconds);