/*
 *    GeoTools - The Open Source Java GIS Toolkit
 *    http://geotools.org
 *
 *    (C) 2011, Open Source Geospatial Foundation (OSGeo)
 *    (C) 2005, Open Geospatial Consortium Inc.
 *    
 *    All Rights Reserved. http://www.opengis.org/legal/
 */
package org.opengis.temporal;

import org.opengis.annotation.UML;
import org.opengis.util.InternationalString;
import static org.opengis.annotation.Obligation.*;
import static org.opengis.annotation.Specification.*;


/**
 * Uses the format specified by ISO 8601 for exchanging information
 * about the duration of a period.
 *
 * @author Stephane Fellah (Image Matters)
 * @author Alexander Petkov
 *
 * @todo Uses Java 1.5 {@link javax.xml.datatype.Duration}.
 *
 * @source $URL: http://svn.osgeo.org/geotools/trunk/modules/library/opengis/src/main/java/org/opengis/temporal/PeriodDuration.java $
 */
@UML(identifier="TM_PeriodDuration", specification=ISO_19108)
public interface PeriodDuration extends Duration {
   /**
    * A mandatory element which designates that the returned string
    * represents the duration of a period.
    */
    @UML(identifier="designator", obligation=MANDATORY, specification=ISO_19108)
    InternationalString getDesignator();

   /**
    * A positive integer, followed by the character "Y",
    * which indicated the number of years in the period.
    */
    @UML(identifier="years", obligation=OPTIONAL, specification=ISO_19108)
    InternationalString getYears();

   /**
    * A positive integer, followed by the character "M",
    * which indicated the number of months in the period.
    */
    @UML(identifier="months", obligation=OPTIONAL, specification=ISO_19108)
    InternationalString getMonths();

   /**
    * A positive integer, followed by the character "D",
    * which indicated the number of days in the period.
    */
    @UML(identifier="days", obligation=OPTIONAL, specification=ISO_19108)
    InternationalString getDays();

   /**
    * Included whenever the sequence includes values for
    * units less than a day.
    */
    @UML(identifier="timeIndicator", obligation=OPTIONAL, specification=ISO_19108)
    InternationalString getTimeIndicator();

   /**
    * A positive integer, followed by the character "H",
    * which indicated the number of hours in the period.
    */
    @UML(identifier="hours", obligation=OPTIONAL, specification=ISO_19108)
    InternationalString getHours();

   /**
    * A positive integer, followed by the character "M",
    * which indicated the number of minutes in the period.
    */
    @UML(identifier="minutes", obligation=OPTIONAL, specification=ISO_19108)
    InternationalString getMinutes();

   /**
    * A positive integer, followed by the character "S",
    * which indicated the number of seconds in the period.
    */
    @UML(identifier="seconds", obligation=OPTIONAL, specification=ISO_19108)
    InternationalString getSeconds();
}