/*
 * 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.yangtools.yang.data.api.schema;

import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.AugmentationIdentifier;
import org.opendaylight.yangtools.yang.model.api.AugmentationSchemaNode;

/**
 * Data instance of <code>augment</code> associated with parent node.
 *
 * <p>
 * Augmentation is addition of subtree defined by other external YANG Model and is schema for subtree is described
 * by an instance of {@link AugmentationSchemaNode} associated with parent node of this node.
 *
 * <p>
 * Augmentation node MUST NOT be direct child of other augmentation node.
 */
public interface AugmentationNode extends DataContainerNode, DataContainerChild, MixinNode {
    @Override
    default Class<AugmentationNode> contract() {
        return AugmentationNode.class;
    }

    /**
     * Gets identifier of augmentation node. Returned identifier of augmentation node contains all possible
     * direct child QNames.
     *
     * <p>
     * This is sufficient to identify instance of augmentation, since RFC6020 states that <code>augment</code>
     * that augment statement must not add multiple nodes from same namespace / module to the target node.
     *
     * @return Identifier which uniquely identifies augmentation in particular subtree.
     */
    @Override
    AugmentationIdentifier getIdentifier();
}