Session: How to Get Entity Change-Vector

  • The change-vector reflects the cluster-wide point in time in which a change occured, and includes the unique database ID, node identifier, and document Etag in the specific node.
  • When a document is downloaded from the server, it contains various metadata information.
    E.g. ID or current change-vector.
  • The current change-vector is stored within the session metadata and is available for each entity using the getChangeVectorFor method from the advanced session operations.


<T> String getChangeVectorFor(T instance)
instance T Instance of an entity for which an Etag will be returned.
Return Value
String Returns the current change-vector for an entity. Throws an exception if the instance is not tracked by the session.


Employee employee = session.load(Employee.class, "employees/1-A");
String changeVector = session.advanced().getChangeVectorFor(employee);