/*
 * Copyright (c) 2013 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.model.api;

import java.util.Optional;

/**
 * Contains methods which retrieve values for description, error message, error app tag and reference (to some external
 * definition, resource or similar).
 */
public interface ConstraintMetaDefinition extends DocumentedNode {

    /**
     * Returns the value of the argument of YANG <code>error-app-tag</code> keyword.
     *
     * @return string with the application tag, or empty if it was not provided.
     */
    Optional<String> getErrorAppTag();

    /**
     * Returns the value of the argument of YANG <code>error-message</code> keyword.
     *
     * @return string with the error message, or empty if it was not provided.
     */
    Optional<String> getErrorMessage();
}