/*$************************************************************************************************
 **
 ** $Id: SingleCRS.java 982 2007-03-27 10:54:51Z desruisseaux $
 **
 ** $URL: https://geoapi.svn.sourceforge.net/svnroot/geoapi/tags/2.1.1/geoapi/src/main/java/org/opengis/referencing/crs/SingleCRS.java $
 **
 ** Copyright (C) 2003-2005 Open GIS Consortium, Inc.
 ** All Rights Reserved. http://www.opengis.org/legal/
 **
 *************************************************************************************************/
package org.opengis.referencing.crs;

import org.opengis.referencing.datum.Datum;
import org.opengis.referencing.cs.CoordinateSystem;
import org.opengis.annotation.UML;

import static org.opengis.annotation.Obligation.*;
import static org.opengis.annotation.Specification.*;


/**
 * Abstract coordinate reference system, consisting of a single
 * {@linkplain CoordinateSystem Coordinate System} and a single
 * {@linkplain Datum Datum} (as opposed to {@linkplain CompoundCRS Compound CRS}).
 *
 * A coordinate reference system consists of an ordered sequence of coordinate system
 * axes that are related to the earth through a datum. A coordinate reference system
 * is defined by one datum and by one coordinate system. Most coordinate reference system
 * do not move relative to the earth, except for engineering coordinate reference systems
 * defined on moving platforms such as cars, ships, aircraft, and spacecraft.
 *
 * Coordinate reference systems are commonly divided into sub-types. The common classification
 * criterion for sub-typing of coordinate reference systems is the way in which they deal with
 * earth curvature. This has a direct effect on the portion of the earth's surface that can be
 * covered by that type of CRS with an acceptable degree of error. The exception to the rule is
 * the subtype "Temporal" which has been added by analogy.
 *
 * @version <A HREF="http://portal.opengeospatial.org/files/?artifact_id=6716">Abstract specification 2.0</A>
 * @author ISO/DIS 19111
 * @author Martin Desruisseaux (IRD)
 * @since GeoAPI 2.0
 *
 * @see org.opengis.referencing.cs.CoordinateSystem
 * @see org.opengis.referencing.datum.Datum
 */
@UML(identifier="SC_SingleCRS", specification=ISO_19111)
public interface SingleCRS extends CoordinateReferenceSystem {
    /**
     * Returns the coordinate system.
     *
     * @rename Expanded the "CS" abbreviation into "CoordinateSystem".
     */
    @UML(identifier="usesCS", obligation=MANDATORY, specification=ISO_19111)
    CoordinateSystem getCoordinateSystem();

    /**
     * Returns the datum.
     */
    @UML(identifier="usesDatum", obligation=MANDATORY, specification=ISO_19111)
    Datum getDatum();
}
