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	/*
	* Copyright (c) 2012, 2015, 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
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	/*
	* This file is available under and governed by the GNU General Public
	* License version 2 only, as published by the Free Software Foundation.
	* However, the following notice accompanied the original version of this
	* file:
	*
	* Copyright (c) 2007-2012, Stephen Colebourne & Michael Nascimento Santos
	*
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are met:
	*
	* * Redistributions of source code must retain the above copyright notice,
	* this list of conditions and the following disclaimer.
	*
	* * Redistributions in binary form must reproduce the above copyright notice,
	* this list of conditions and the following disclaimer in the documentation
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	*
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	* may be used to endorse or promote products derived from this software
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	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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	package java.time;

	import static java.time.temporal.ChronoField.MONTH_OF_YEAR;
	import static java.time.temporal.ChronoUnit.MONTHS;

	import java.time.chrono.Chronology;
	import java.time.chrono.IsoChronology;
	import java.time.format.DateTimeFormatterBuilder;
	import java.time.format.TextStyle;
	import java.time.temporal.ChronoField;
	import java.time.temporal.Temporal;
	import java.time.temporal.TemporalAccessor;
	import java.time.temporal.TemporalAdjuster;
	import java.time.temporal.TemporalField;
	import java.time.temporal.TemporalQueries;
	import java.time.temporal.TemporalQuery;
	import java.time.temporal.UnsupportedTemporalTypeException;
	import java.time.temporal.ValueRange;
	import java.util.Locale;

	/**
	* A month-of-year, such as 'July'.
	* <p>
	* {@code Month} is an enum representing the 12 months of the year -
	* January, February, March, April, May, June, July, August, September, October,
	* November and December.
	* <p>
	* In addition to the textual enum name, each month-of-year has an {@code int} value.
	* The {@code int} value follows normal usage and the ISO-8601 standard,
	* from 1 (January) to 12 (December). It is recommended that applications use the enum
	* rather than the {@code int} value to ensure code clarity.
	* <p>
	* <b>Do not use {@code ordinal()} to obtain the numeric representation of {@code Month}.
	* Use {@code getValue()} instead.</b>
	* <p>
	* This enum represents a common concept that is found in many calendar systems.
	* As such, this enum may be used by any calendar system that has the month-of-year
	* concept defined exactly equivalent to the ISO-8601 calendar system.
	*
	* @implSpec
	* This is an immutable and thread-safe enum.
	*
	* @since 1.8
	*/
	public enum Month implements TemporalAccessor, TemporalAdjuster {

	/**
	* The singleton instance for the month of January with 31 days.
	* This has the numeric value of {@code 1}.
	*/
	JANUARY,
	/**
	* The singleton instance for the month of February with 28 days, or 29 in a leap year.
	* This has the numeric value of {@code 2}.
	*/
	FEBRUARY,
	/**
	* The singleton instance for the month of March with 31 days.
	* This has the numeric value of {@code 3}.
	*/
	MARCH,
	/**
	* The singleton instance for the month of April with 30 days.
	* This has the numeric value of {@code 4}.
	*/
	APRIL,
	/**
	* The singleton instance for the month of May with 31 days.
	* This has the numeric value of {@code 5}.
	*/
	MAY,
	/**
	* The singleton instance for the month of June with 30 days.
	* This has the numeric value of {@code 6}.
	*/
	JUNE,
	/**
	* The singleton instance for the month of July with 31 days.
	* This has the numeric value of {@code 7}.
	*/
	JULY,
	/**
	* The singleton instance for the month of August with 31 days.
	* This has the numeric value of {@code 8}.
	*/
	AUGUST,
	/**
	* The singleton instance for the month of September with 30 days.
	* This has the numeric value of {@code 9}.
	*/
	SEPTEMBER,
	/**
	* The singleton instance for the month of October with 31 days.
	* This has the numeric value of {@code 10}.
	*/
	OCTOBER,
	/**
	* The singleton instance for the month of November with 30 days.
	* This has the numeric value of {@code 11}.
	*/
	NOVEMBER,
	/**
	* The singleton instance for the month of December with 31 days.
	* This has the numeric value of {@code 12}.
	*/
	DECEMBER;
	/**
	* Private cache of all the constants.
	*/
	private static final Month[] ENUMS = Month.values();

	//-----------------------------------------------------------------------
	/**
	* Obtains an instance of {@code Month} from an {@code int} value.
	* <p>
	* {@code Month} is an enum representing the 12 months of the year.
	* This factory allows the enum to be obtained from the {@code int} value.
	* The {@code int} value follows the ISO-8601 standard, from 1 (January) to 12 (December).
	*
	* @param month the month-of-year to represent, from 1 (January) to 12 (December)
	* @return the month-of-year, not null
	* @throws DateTimeException if the month-of-year is invalid
	*/
	public static Month of(int month) {
	if (month < 1 \|\| month > 12) {
	throw new DateTimeException("Invalid value for MonthOfYear: " + month);
	}
	return ENUMS[month - 1];
	}

	//-----------------------------------------------------------------------
	/**
	* Obtains an instance of {@code Month} from a temporal object.
	* <p>
	* This obtains a month based on the specified temporal.
	* A {@code TemporalAccessor} represents an arbitrary set of date and time information,
	* which this factory converts to an instance of {@code Month}.
	* <p>
	* The conversion extracts the {@link ChronoField#MONTH_OF_YEAR MONTH_OF_YEAR} field.
	* The extraction is only permitted if the temporal object has an ISO
	* chronology, or can be converted to a {@code LocalDate}.
	* <p>
	* This method matches the signature of the functional interface {@link TemporalQuery}
	* allowing it to be used as a query via method reference, {@code Month::from}.
	*
	* @param temporal the temporal object to convert, not null
	* @return the month-of-year, not null
	* @throws DateTimeException if unable to convert to a {@code Month}
	*/
	public static Month from(TemporalAccessor temporal) {
	if (temporal instanceof Month) {
	return (Month) temporal;
	}
	try {
	if (IsoChronology.INSTANCE.equals(Chronology.from(temporal)) == false) {
	temporal = LocalDate.from(temporal);
	}
	return of(temporal.get(MONTH_OF_YEAR));
	} catch (DateTimeException ex) {
	throw new DateTimeException("Unable to obtain Month from TemporalAccessor: " +
	temporal + " of type " + temporal.getClass().getName(), ex);
	}
	}

	//-----------------------------------------------------------------------
	/**
	* Gets the month-of-year {@code int} value.
	* <p>
	* The values are numbered following the ISO-8601 standard,
	* from 1 (January) to 12 (December).
	*
	* @return the month-of-year, from 1 (January) to 12 (December)
	*/
	public int getValue() {
	return ordinal() + 1;
	}

	//-----------------------------------------------------------------------
	/**
	* Gets the textual representation, such as 'Jan' or 'December'.
	* <p>
	* This returns the textual name used to identify the month-of-year,
	* suitable for presentation to the user.
	* The parameters control the style of the returned text and the locale.
	* <p>
	* If no textual mapping is found then the {@link #getValue() numeric value} is returned.
	*
	* @param style the length of the text required, not null
	* @param locale the locale to use, not null
	* @return the text value of the month-of-year, not null
	*/
	public String getDisplayName(TextStyle style, Locale locale) {
	return new DateTimeFormatterBuilder().appendText(MONTH_OF_YEAR, style).toFormatter(locale).format(this);
	}

	//-----------------------------------------------------------------------
	/**
	* Checks if the specified field is supported.
	* <p>
	* This checks if this month-of-year can be queried for the specified field.
	* If false, then calling the {@link #range(TemporalField) range} and
	* {@link #get(TemporalField) get} methods will throw an exception.
	* <p>
	* If the field is {@link ChronoField#MONTH_OF_YEAR MONTH_OF_YEAR} then
	* this method returns true.
	* All other {@code ChronoField} instances will return false.
	* <p>
	* If the field is not a {@code ChronoField}, then the result of this method
	* is obtained by invoking {@code TemporalField.isSupportedBy(TemporalAccessor)}
	* passing {@code this} as the argument.
	* Whether the field is supported is determined by the field.
	*
	* @param field the field to check, null returns false
	* @return true if the field is supported on this month-of-year, false if not
	*/
	@Override
	public boolean isSupported(TemporalField field) {
	if (field instanceof ChronoField) {
	return field == MONTH_OF_YEAR;
	}
	return field != null && field.isSupportedBy(this);
	}

	/**
	* Gets the range of valid values for the specified field.
	* <p>
	* The range object expresses the minimum and maximum valid values for a field.
	* This month is used to enhance the accuracy of the returned range.
	* If it is not possible to return the range, because the field is not supported
	* or for some other reason, an exception is thrown.
	* <p>
	* If the field is {@link ChronoField#MONTH_OF_YEAR MONTH_OF_YEAR} then the
	* range of the month-of-year, from 1 to 12, will be returned.
	* All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
	* <p>
	* If the field is not a {@code ChronoField}, then the result of this method
	* is obtained by invoking {@code TemporalField.rangeRefinedBy(TemporalAccessor)}
	* passing {@code this} as the argument.
	* Whether the range can be obtained is determined by the field.
	*
	* @param field the field to query the range for, not null
	* @return the range of valid values for the field, not null
	* @throws DateTimeException if the range for the field cannot be obtained
	* @throws UnsupportedTemporalTypeException if the field is not supported
	*/
	@Override
	public ValueRange range(TemporalField field) {
	if (field == MONTH_OF_YEAR) {
	return field.range();
	}
	return TemporalAccessor.super.range(field);
	}

	/**
	* Gets the value of the specified field from this month-of-year as an {@code int}.
	* <p>
	* This queries this month for the value of the specified field.
	* The returned value will always be within the valid range of values for the field.
	* If it is not possible to return the value, because the field is not supported
	* or for some other reason, an exception is thrown.
	* <p>
	* If the field is {@link ChronoField#MONTH_OF_YEAR MONTH_OF_YEAR} then the
	* value of the month-of-year, from 1 to 12, will be returned.
	* All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
	* <p>
	* If the field is not a {@code ChronoField}, then the result of this method
	* is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
	* passing {@code this} as the argument. Whether the value can be obtained,
	* and what the value represents, is determined by the field.
	*
	* @param field the field to get, not null
	* @return the value for the field, within the valid range of values
	* @throws DateTimeException if a value for the field cannot be obtained or
	* the value is outside the range of valid values for the field
	* @throws UnsupportedTemporalTypeException if the field is not supported or
	* the range of values exceeds an {@code int}
	* @throws ArithmeticException if numeric overflow occurs
	*/
	@Override
	public int get(TemporalField field) {
	if (field == MONTH_OF_YEAR) {
	return getValue();
	}
	return TemporalAccessor.super.get(field);
	}

	/**
	* Gets the value of the specified field from this month-of-year as a {@code long}.
	* <p>
	* This queries this month for the value of the specified field.
	* If it is not possible to return the value, because the field is not supported
	* or for some other reason, an exception is thrown.
	* <p>
	* If the field is {@link ChronoField#MONTH_OF_YEAR MONTH_OF_YEAR} then the
	* value of the month-of-year, from 1 to 12, will be returned.
	* All other {@code ChronoField} instances will throw an {@code UnsupportedTemporalTypeException}.
	* <p>
	* If the field is not a {@code ChronoField}, then the result of this method
	* is obtained by invoking {@code TemporalField.getFrom(TemporalAccessor)}
	* passing {@code this} as the argument. Whether the value can be obtained,
	* and what the value represents, is determined by the field.
	*
	* @param field the field to get, not null
	* @return the value for the field
	* @throws DateTimeException if a value for the field cannot be obtained
	* @throws UnsupportedTemporalTypeException if the field is not supported
	* @throws ArithmeticException if numeric overflow occurs
	*/
	@Override
	public long getLong(TemporalField field) {
	if (field == MONTH_OF_YEAR) {
	return getValue();
	} else if (field instanceof ChronoField) {
	throw new UnsupportedTemporalTypeException("Unsupported field: " + field);
	}
	return field.getFrom(this);
	}

	//-----------------------------------------------------------------------
	/**
	* Returns the month-of-year that is the specified number of months after this one.
	* <p>
	* The calculation rolls around the end of the year from December to January.
	* The specified period may be negative.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param months the months to add, positive or negative
	* @return the resulting month, not null
	*/
	public Month plus(long months) {
	int amount = (int) (months % 12);
	return ENUMS[(ordinal() + (amount + 12)) % 12];
	}

	/**
	* Returns the month-of-year that is the specified number of months before this one.
	* <p>
	* The calculation rolls around the start of the year from January to December.
	* The specified period may be negative.
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param months the months to subtract, positive or negative
	* @return the resulting month, not null
	*/
	public Month minus(long months) {
	return plus(-(months % 12));
	}

	//-----------------------------------------------------------------------
	/**
	* Gets the length of this month in days.
	* <p>
	* This takes a flag to determine whether to return the length for a leap year or not.
	* <p>
	* February has 28 days in a standard year and 29 days in a leap year.
	* April, June, September and November have 30 days.
	* All other months have 31 days.
	*
	* @param leapYear true if the length is required for a leap year
	* @return the length of this month in days, from 28 to 31
	*/
	public int length(boolean leapYear) {
	switch (this) {
	case FEBRUARY:
	return (leapYear ? 29 : 28);
	case APRIL:
	case JUNE:
	case SEPTEMBER:
	case NOVEMBER:
	return 30;
	default:
	return 31;
	}
	}

	/**
	* Gets the minimum length of this month in days.
	* <p>
	* February has a minimum length of 28 days.
	* April, June, September and November have 30 days.
	* All other months have 31 days.
	*
	* @return the minimum length of this month in days, from 28 to 31
	*/
	public int minLength() {
	switch (this) {
	case FEBRUARY:
	return 28;
	case APRIL:
	case JUNE:
	case SEPTEMBER:
	case NOVEMBER:
	return 30;
	default:
	return 31;
	}
	}

	/**
	* Gets the maximum length of this month in days.
	* <p>
	* February has a maximum length of 29 days.
	* April, June, September and November have 30 days.
	* All other months have 31 days.
	*
	* @return the maximum length of this month in days, from 29 to 31
	*/
	public int maxLength() {
	switch (this) {
	case FEBRUARY:
	return 29;
	case APRIL:
	case JUNE:
	case SEPTEMBER:
	case NOVEMBER:
	return 30;
	default:
	return 31;
	}
	}

	//-----------------------------------------------------------------------
	/**
	* Gets the day-of-year corresponding to the first day of this month.
	* <p>
	* This returns the day-of-year that this month begins on, using the leap
	* year flag to determine the length of February.
	*
	* @param leapYear true if the length is required for a leap year
	* @return the day of year corresponding to the first day of this month, from 1 to 336
	*/
	public int firstDayOfYear(boolean leapYear) {
	int leap = leapYear ? 1 : 0;
	switch (this) {
	case JANUARY:
	return 1;
	case FEBRUARY:
	return 32;
	case MARCH:
	return 60 + leap;
	case APRIL:
	return 91 + leap;
	case MAY:
	return 121 + leap;
	case JUNE:
	return 152 + leap;
	case JULY:
	return 182 + leap;
	case AUGUST:
	return 213 + leap;
	case SEPTEMBER:
	return 244 + leap;
	case OCTOBER:
	return 274 + leap;
	case NOVEMBER:
	return 305 + leap;
	case DECEMBER:
	default:
	return 335 + leap;
	}
	}

	/**
	* Gets the month corresponding to the first month of this quarter.
	* <p>
	* The year can be divided into four quarters.
	* This method returns the first month of the quarter for the base month.
	* January, February and March return January.
	* April, May and June return April.
	* July, August and September return July.
	* October, November and December return October.
	*
	* @return the first month of the quarter corresponding to this month, not null
	*/
	public Month firstMonthOfQuarter() {
	return ENUMS[(ordinal() / 3) * 3];
	}

	//-----------------------------------------------------------------------
	/**
	* Queries this month-of-year using the specified query.
	* <p>
	* This queries this month-of-year using the specified query strategy object.
	* The {@code TemporalQuery} object defines the logic to be used to
	* obtain the result. Read the documentation of the query to understand
	* what the result of this method will be.
	* <p>
	* The result of this method is obtained by invoking the
	* {@link TemporalQuery#queryFrom(TemporalAccessor)} method on the
	* specified query passing {@code this} as the argument.
	*
	* @param <R> the type of the result
	* @param query the query to invoke, not null
	* @return the query result, null may be returned (defined by the query)
	* @throws DateTimeException if unable to query (defined by the query)
	* @throws ArithmeticException if numeric overflow occurs (defined by the query)
	*/
	@SuppressWarnings("unchecked")
	@Override
	public <R> R query(TemporalQuery<R> query) {
	if (query == TemporalQueries.chronology()) {
	return (R) IsoChronology.INSTANCE;
	} else if (query == TemporalQueries.precision()) {
	return (R) MONTHS;
	}
	return TemporalAccessor.super.query(query);
	}

	/**
	* Adjusts the specified temporal object to have this month-of-year.
	* <p>
	* This returns a temporal object of the same observable type as the input
	* with the month-of-year changed to be the same as this.
	* <p>
	* The adjustment is equivalent to using {@link Temporal#with(TemporalField, long)}
	* passing {@link ChronoField#MONTH_OF_YEAR} as the field.
	* If the specified temporal object does not use the ISO calendar system then
	* a {@code DateTimeException} is thrown.
	* <p>
	* In most cases, it is clearer to reverse the calling pattern by using
	* {@link Temporal#with(TemporalAdjuster)}:
	* <pre>
	* // these two lines are equivalent, but the second approach is recommended
	* temporal = thisMonth.adjustInto(temporal);
	* temporal = temporal.with(thisMonth);
	* </pre>
	* <p>
	* For example, given a date in May, the following are output:
	* <pre>
	* dateInMay.with(JANUARY); // four months earlier
	* dateInMay.with(APRIL); // one months earlier
	* dateInMay.with(MAY); // same date
	* dateInMay.with(JUNE); // one month later
	* dateInMay.with(DECEMBER); // seven months later
	* </pre>
	* <p>
	* This instance is immutable and unaffected by this method call.
	*
	* @param temporal the target object to be adjusted, not null
	* @return the adjusted object, not null
	* @throws DateTimeException if unable to make the adjustment
	* @throws ArithmeticException if numeric overflow occurs
	*/
	@Override
	public Temporal adjustInto(Temporal temporal) {
	if (Chronology.from(temporal).equals(IsoChronology.INSTANCE) == false) {
	throw new DateTimeException("Adjustment only supported on ISO date-time");
	}
	return temporal.with(MONTH_OF_YEAR, getValue());
	}

	}

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