+ * Registers a {@link DataTreeChangeListener} to receive notifications when data changes under a given path in the
+ * conceptual data tree.
+ *
+ * <p>
+ * You are able to register for notifications for any node or subtree which can be represented using
+ * {@link DataTreeIdentifier}.
+ *
+ * <p>
+ * You are able to register for data change notifications for a subtree or leaf even if it does not exist. You will
+ * receive notification once that node is created.
+ *
+ * <p>
+ * If there is any pre-existing data in the data tree for the path for which you are registering, you will receive
+ * an initial data change event, which will contain all pre-existing data, marked as created.
+ *
+ * <p>
+ * This method returns a {@link Registration} object. To "unregister" your listener for changes call the
+ * {@link Registration#close()} method on the returned object.
+ *
+ * <p>
+ * You <b>MUST</b> explicitly unregister your listener when you no longer want to receive notifications. This is
+ * especially true in OSGi environments, where failure to do so during bundle shutdown can lead to stale listeners
+ * being still registered.
+ *
+ * @param treeId Data tree identifier of the subtree which should be watched for changes
+ * @param listener Listener instance which is being registered
+ * @return a Registration object, which may be used to unregister your listener using {@link Registration#close()}
+ * to stop delivery of change events.
+ */
+ <T extends DataObject> @NonNull Registration registerTreeChangeListener(
+ @NonNull DataTreeIdentifier<T> treeId, @NonNull DataTreeChangeListener<T> listener);
+
+ /**
+ * Registers a {@link DataTreeChangeListener} to receive notifications when data changes under a given path in the
+ * conceptual data tree, with legacy semantics, where no events are delivered if this "cluster node" (further
+ * undefined) is a "leader" (also not explicitly undefined).
+ *
+ * <p>
+ * The sole known implementation, the Akka-based datastore, defines the difference in terms of RAFT, suspending
+ * even delivery when the RAFT leader is not local. Even when there may be valid use cases for this, RAFT there
+ * is a storage backend whose lifecycle is disconnected from this object.
+ *
+ * <p>
+ * Aside from the above difference, this method is equivalent to
+ * {@link #registerTreeChangeListener(DataTreeIdentifier, DataTreeChangeListener)}. If you are unable to migrate,
+ * please contact us on <a href="email:discuss@lists.opendaylight.org">the mailing list</a>
+ *
+ * @param treeId Data tree identifier of the subtree which should be watched for changes.
+ * @param listener Listener instance which is being registered
+ * @return A {@link Registration} object, which may be used to unregister your listener using
+ * {@link Registration#close()} to stop delivery of change events.
+ * @throws NullPointerException if any of the arguments is {@code null}
+ */
+ @Deprecated(since = "13.0.0", forRemoval = true)
+ <T extends DataObject> @NonNull Registration registerLegacyTreeChangeListener(@NonNull DataTreeIdentifier<T> treeId,
+ @NonNull DataTreeChangeListener<T> listener);
+
+ /**
+ * Registers a {@link DataTreeChangeListener} to receive notifications when data changes under a given path in the
+ * conceptual data tree.
+ *
+ * <p>
+ * You are able to register for notifications for any node or subtree which can be represented using
+ * {@link DataTreeIdentifier}.
+ *
+ * <p>
+ * You are able to register for data change notifications for a subtree or leaf even if it does not exist. You will
+ * receive notification once that node is created.
+ *
+ * <p>
+ * If there is any pre-existing data in the data tree for the path for which you are registering, you will receive
+ * an initial data change event, which will contain all pre-existing data, marked as created.
+ *
+ * <p>
+ * This method returns a {@link Registration} object. To "unregister" your listener for changes call the
+ * {@link Registration#close()} method on the returned object.
+ *
+ * <p>
+ * You <b>MUST</b> explicitly unregister your listener when you no longer want to receive notifications. This is
+ * especially true in OSGi environments, where failure to do so during bundle shutdown can lead to stale listeners
+ * being still registered.
+ *
+ * @param treeId Data tree identifier of the subtree which should be watched for changes
+ * @param listener Listener instance which is being registered
+ * @return a Registration object, which may be used to unregister your listener using {@link Registration#close()}
+ * to stop delivery of change events.
+ * @deprecated This interface relies on magic of {@link ClusteredDataTreeChangeListener}. See
+ * {@link #registerLegacyTreeChangeListener(DataTreeIdentifier, DataTreeChangeListener)} for migration
+ * guidance.
+ */
+ @Deprecated(since = "13.0.0", forRemoval = true)
+ default <T extends DataObject> @NonNull Registration registerDataTreeChangeListener(
+ final @NonNull DataTreeIdentifier<T> treeId, final @NonNull DataTreeChangeListener<T> listener) {
+ return listener instanceof ClusteredDataTreeChangeListener ? registerTreeChangeListener(treeId, listener)
+ : registerLegacyTreeChangeListener(treeId, listener);
+ }
+
+ /**
+ * Registers a {@link ClusteredDataTreeChangeListener} to receive notifications when data changes under a given path
+ * in the conceptual data tree. This is a migration shorthand for
+ * {@code registerDataTreeListener(treeId, listener)}.
+ *
+ * @param treeId Data tree identifier of the subtree which should be watched for changes.
+ * @param listener Listener instance which is being registered
+ * @return A {@link Registration} object, which may be used to unregister your listener using
+ * {@link Registration#close()} to stop delivery of change events.
+ * @throws NullPointerException if any of the arguments is {@code null}
+ * @deprecated Use {@link #registerTreeChangeListener(DataTreeIdentifier, DataTreeChangeListener)} instead.
+ */
+ @Deprecated(since = "13.0.0", forRemoval = true)
+ default <T extends DataObject> @NonNull Registration registerDataTreeChangeListener(
+ final @NonNull DataTreeIdentifier<T> treeId, final @NonNull ClusteredDataTreeChangeListener<T> listener) {
+ return registerTreeChangeListener(treeId, listener);
+ }
+
+ /**
+ * Registers a {@link DataTreeChangeListener} to receive notifications when data changes under a given path in the
+ * conceptual data tree.
+ *