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	/*
	* Copyright (c) 2003, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code 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 General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package sun.util.calendar;

	import java.util.HashMap;
	import java.util.Map;

	public class CalendarUtils {

	/**
	* Returns whether the specified year is a leap year in the Gregorian
	* calendar system.
	*
	* @param gregorianYear a Gregorian calendar year
	* @return true if the given year is a leap year in the Gregorian
	* calendar system.
	* @see CalendarDate#isLeapYear
	*/
	public static final boolean isGregorianLeapYear(int gregorianYear) {
	return (((gregorianYear % 4) == 0)
	&& (((gregorianYear % 100) != 0) \|\| ((gregorianYear % 400) == 0)));
	}

	/**
	* Returns whether the specified year is a leap year in the Julian
	* calendar system. The year number must be a normalized one
	* (e.g., 45 B.C.E. is 1-45).
	*
	* @param normalizedJulianYear a normalized Julian calendar year
	* @return true if the given year is a leap year in the Julian
	* calendar system.
	* @see CalendarDate#isLeapYear
	*/
	public static final boolean isJulianLeapYear(int normalizedJulianYear) {
	return (normalizedJulianYear % 4) == 0;
	}

	/**
	* Divides two integers and returns the floor of the quotient.
	* For example, <code>floorDivide(-1, 4)</code> returns -1 while
	* -1/4 is 0.
	*
	* @param n the numerator
	* @param d a divisor that must be greater than 0
	* @return the floor of the quotient
	*/
	public static final long floorDivide(long n, long d) {
	return ((n >= 0) ?
	(n / d) : (((n + 1L) / d) - 1L));
	}

	/**
	* Divides two integers and returns the floor of the quotient.
	* For example, <code>floorDivide(-1, 4)</code> returns -1 while
	* -1/4 is 0.
	*
	* @param n the numerator
	* @param d a divisor that must be greater than 0
	* @return the floor of the quotient
	*/
	public static final int floorDivide(int n, int d) {
	return ((n >= 0) ?
	(n / d) : (((n + 1) / d) - 1));
	}

	/**
	* Divides two integers and returns the floor of the quotient and
	* the modulus remainder. For example,
	* <code>floorDivide(-1,4)</code> returns <code>-1</code> with
	* <code>3</code> as its remainder, while <code>-1/4</code> is
	* <code>0</code> and <code>-1%4</code> is <code>-1</code>.
	*
	* @param n the numerator
	* @param d a divisor which must be {@literal > 0}
	* @param r an array of at least one element in which the value
	* <code>mod(n, d)</code> is returned.
	* @return the floor of the quotient.
	*/
	public static final int floorDivide(int n, int d, int[] r) {
	if (n >= 0) {
	r[0] = n % d;
	return n / d;
	}
	int q = ((n + 1) / d) - 1;
	r[0] = n - (q * d);
	return q;
	}

	/**
	* Divides two integers and returns the floor of the quotient and
	* the modulus remainder. For example,
	* <code>floorDivide(-1,4)</code> returns <code>-1</code> with
	* <code>3</code> as its remainder, while <code>-1/4</code> is
	* <code>0</code> and <code>-1%4</code> is <code>-1</code>.
	*
	* @param n the numerator
	* @param d a divisor which must be {@literal > 0}
	* @param r an array of at least one element in which the value
	* <code>mod(n, d)</code> is returned.
	* @return the floor of the quotient.
	*/
	public static final int floorDivide(long n, int d, int[] r) {
	if (n >= 0) {
	r[0] = (int)(n % d);
	return (int)(n / d);
	}
	int q = (int)(((n + 1) / d) - 1);
	r[0] = (int)(n - (q * d));
	return q;
	}

	public static final long mod(long x, long y) {
	return (x - y * floorDivide(x, y));
	}

	public static final int mod(int x, int y) {
	return (x - y * floorDivide(x, y));
	}

	public static final int amod(int x, int y) {
	int z = mod(x, y);
	return (z == 0) ? y : z;
	}

	public static final long amod(long x, long y) {
	long z = mod(x, y);
	return (z == 0) ? y : z;
	}

	/**
	* Mimics sprintf(buf, "%0*d", decaimal, width).
	*/
	public static final StringBuilder sprintf0d(StringBuilder sb, int value, int width) {
	long d = value;
	if (d < 0) {
	sb.append('-');
	d = -d;
	--width;
	}
	int n = 10;
	for (int i = 2; i < width; i++) {
	n *= 10;
	}
	for (int i = 1; i < width && d < n; i++) {
	sb.append('0');
	n /= 10;
	}
	sb.append(d);
	return sb;
	}

	public static final StringBuffer sprintf0d(StringBuffer sb, int value, int width) {
	long d = value;
	if (d < 0) {
	sb.append('-');
	d = -d;
	--width;
	}
	int n = 10;
	for (int i = 2; i < width; i++) {
	n *= 10;
	}
	for (int i = 1; i < width && d < n; i++) {
	sb.append('0');
	n /= 10;
	}
	sb.append(d);
	return sb;
	}
	}

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