/*
* -----------------------------------------------------------------------
* Copyright © 2013-2014 Meno Hochschild, <http://www.menodata.de/>
* -----------------------------------------------------------------------
* This file (GregorianDate.java) is part of project Time4J.
*
* Time4J is free software: You can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation, either version 2.1 of the License, or
* (at your option) any later version.
*
* Time4J is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with Time4J. If not, see <http://www.gnu.org/licenses/>.
* -----------------------------------------------------------------------
*/
package net.time4j.base;
/**
* <p>Defines a common calendar date which is based on gregorian calendar
* rules. </p>
*
* @author Meno Hochschild
*/
/*[deutsch]
* <p>Definiert ein allgemeines Datum, das auf den gregorianischen
* Kalenderregeln beruht. </p>
*
* @author Meno Hochschild
*/
public interface GregorianDate {
//~ Methoden ----------------------------------------------------------
/**
* <p>Yields the proleptic year according to ISO-8601. </p>
*
* <p>The term <i>proleptic</i> means that the gregorian calendar rules
* are applied backwards even before the introduction of this calendar.
* Second: The year numbering is just the mathematical one as defined
* in ISO-8601 such that there is a year zero and even negative years:
* -2 = BC 3, -1 = BC 2, 0 = BC 1, 1 = AD 1, 2 = AD 2, ... </p>
*
* @return proleptic iso year in range
* {@link GregorianMath#MIN_YEAR} - {@link GregorianMath#MAX_YEAR}
*/
/*[deutsch]
* <p>Liefert das proleptische Jahr entsprechend dem ISO-8601-Standard. </p>
*
* <p>Der Begriff <i>proleptic</i> bedeutet, daß die gregorianischen
* Kalenderregeln rückwärts sogar vor der Einführung
* des gregorianischen Kalenders angewandt werden. Zweitens: Die
* Jahreszählung ist eine rein mathematische wie in ISO-8601
* definiert (und von Astronomen benutzt) so, daß es ein Jahr 0
* und sogar negative Jahre gibt:
* -2 = BC 3, -1 = BC 2, 0 = BC 1, 1 = AD 1, 2 = AD 2, ... </p>
*
* @return proleptic iso year in range
* {@link GregorianMath#MIN_YEAR} - {@link GregorianMath#MAX_YEAR}
*/
int getYear();
/**
* <p>Yields the gregorian month as integer. </p>
*
* @return gregorian month in range (1 = January, ..., 12 = December)
*/
/*[deutsch]
* <p>Liefert den gregorianischen Monat als Integer. </p>
*
* @return gregorian month in range (1 = January, ..., 12 = December)
*/
int getMonth();
/**
* <p>Yields the day of month. </p>
*
* @return day of month in range {@code 1 <= dayOfMonth <= 31}
*/
/*[deutsch]
* <p>Liefert den Tag des Monats. </p>
*
* @return day of month in range {@code 1 <= dayOfMonth <= 31}
*/
int getDayOfMonth();
/**
* <p>Yields a canonical representation in ISO-format
* "YYYY-MM-DD". </p>
*
* @return date in ISO-8601-format YYYY-MM-DD
*/
/*[deutsch]
* <p>Liefert eine kanonische Darstellung im ISO-Format
* "YYYY-MM-DD". </p>
*
* @return date in ISO-8601-format YYYY-MM-DD
*/
@Override
String toString();
}