+/*
+ * Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.opendaylight.controller.md.sal.dom.store.impl.tree.spi;
+
+import org.opendaylight.controller.md.sal.dom.store.impl.tree.StoreTreeNode;
+import org.opendaylight.yangtools.concepts.Identifiable;
+import org.opendaylight.yangtools.yang.data.api.InstanceIdentifier.PathArgument;
+import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
+
+import com.google.common.primitives.UnsignedLong;
+
+/*
+ * A very basic data tree node. It has a version (when it was last modified),
+ * a subtree version (when any of its children were modified) and some read-only
+ * data.
+ */
+public interface TreeNode extends Identifiable<PathArgument>, StoreTreeNode<TreeNode> {
+ /**
+ * Get the data node version.
+ *
+ * @return Current data node version.
+ */
+ UnsignedLong getVersion();
+
+ /**
+ * Get the subtree version.
+ *
+ * @return Current subtree version.
+ */
+ UnsignedLong getSubtreeVersion();
+
+ /**
+ * Get a read-only view of the underlying data.
+ *
+ * @return Unmodifiable view of the underlying data.
+ */
+ NormalizedNode<?, ?> getData();
+
+ /**
+ * Get a mutable, isolated copy of the node.
+ *
+ * @return Mutable copy
+ */
+ MutableTreeNode mutable();
+}