001/*
002 *    GeoAPI - Java interfaces for OGC/ISO standards
003 *    Copyright © 2003-2023 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.geometry.coordinate;
019
020import org.opengis.geometry.DirectPosition;
021import org.opengis.geometry.primitive.Point;
022import org.opengis.annotation.UML;
023import org.opengis.annotation.Classifier;
024import org.opengis.annotation.Stereotype;
025
026import static org.opengis.annotation.Obligation.*;
027import static org.opengis.annotation.Specification.*;
028
029
030/**
031 * A type consisting of either a direct position or of a point from which a direct position shall be obtained.
032 * The use of this data type allows the identification of a position either directly as a coordinate tuple
033 * (variant direct) or indirectly as a {@linkplain Point point} (variant indirect).
034 *
035 * @departure constraint
036 *   ISO 19107 defines {@code Position} as a {@code union} of {@code DirectPosition} and {@code Point}
037 *   but unions are not allowed in Java. GeoAPI defines {@code Position} as the base interface of both
038 *   types, and the Java {@code instanceof} operation should be used for determining the type.
039 *
040 * @author  Martin Desruisseaux (IRD)
041 * @version 3.1
042 * @since   1.0
043 *
044 * @deprecated The {@code GM_Position} union has been removed in ISO 19107:2019.
045 */
046@Deprecated(since = "3.1")
047@Classifier(Stereotype.UNION)
048@UML(identifier="GM_Position", specification=ISO_19107, version=2003)
049public interface Position {
050    /**
051     * Returns the direct position. This method shall never return {@code null}, but may return
052     * {@code this} if invoked on an object which is already a {@code DirectPosition} instance.
053     *
054     * @return the direct position (may be {@code this}).
055     */
056    @UML(identifier="direct", obligation=CONDITIONAL, specification=ISO_19107)
057    DirectPosition getDirectPosition();
058}