001/*
002 *    GeoAPI - Java interfaces for OGC/ISO standards
003 *    Copyright © 2004-2023 Open Geospatial Consortium, Inc.
004 *    http://www.geoapi.org
005 *
006 *    Licensed under the Apache License, Version 2.0 (the "License");
007 *    you may not use this file except in compliance with the License.
008 *    You may obtain a copy of the License at
009 *
010 *        http://www.apache.org/licenses/LICENSE-2.0
011 *
012 *    Unless required by applicable law or agreed to in writing, software
013 *    distributed under the License is distributed on an "AS IS" BASIS,
014 *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 *    See the License for the specific language governing permissions and
016 *    limitations under the License.
017 */
018package org.opengis.metadata;
019
020import java.util.Collection;
021import java.util.Collections;
022import org.opengis.metadata.citation.OnlineResource;
023import org.opengis.annotation.UML;
024
025import static org.opengis.annotation.Obligation.*;
026import static org.opengis.annotation.Specification.*;
027
028
029/**
030 * Information describing metadata extensions.
031 *
032 * @author  Martin Desruisseaux (IRD)
033 * @version 3.1
034 * @since   2.0
035 */
036@UML(identifier="MD_MetadataExtensionInformation", specification=ISO_19115)
037public interface MetadataExtensionInformation {
038    /**
039     * Information about on-line sources containing the community profile name and
040     * the extended metadata elements and information for all new metadata elements.
041     *
042     * @return on-line sources to community profile name and extended metadata elements, or {@code null}.
043     */
044    @UML(identifier="extensionOnLineResource", obligation=OPTIONAL, specification=ISO_19115)
045    default OnlineResource getExtensionOnLineResource() {
046        return null;
047    }
048
049    /**
050     * Provides information about a new metadata element, not found in ISO 19115,
051     * which is required to describe the resource.
052     *
053     * @return new metadata element not found in ISO 19115.
054     */
055    @UML(identifier="extendedElementInformation", obligation=OPTIONAL, specification=ISO_19115)
056    default Collection<? extends ExtendedElementInformation> getExtendedElementInformation() {
057        return Collections.emptyList();
058    }
059}