| /* |
| * Copyright (c) 2012, 2013, 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. |
| */ |
| |
| /* |
| * 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 |
| * and/or other materials provided with the distribution. |
| * |
| * * Neither the name of JSR-310 nor the names of its contributors |
| * may be used to endorse or promote products derived from this software |
| * without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
| * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR |
| * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
| * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
| * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
| * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
| * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
| * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
| * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| 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.Queries; |
| import java.time.temporal.Temporal; |
| import java.time.temporal.TemporalAccessor; |
| import java.time.temporal.TemporalAdjuster; |
| import java.time.temporal.TemporalField; |
| import java.time.temporal.TemporalQuery; |
| 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. |
| * |
| * <h3>Specification for implementors</h3> |
| * 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 in queries 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.getClass(), 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 a {@code DateTimeException}. |
| * <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 |
| */ |
| @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 for 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 a {@code DateTimeException}. |
| * <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 |
| * @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 for 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 a {@code DateTimeException}. |
| * <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 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 DateTimeException("Unsupported field: " + field.getName()); |
| } |
| return field.getFrom(this); |
| } |
| |
| //----------------------------------------------------------------------- |
| /** |
| * Returns the month-of-year that is the specified number of quarters 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 == Queries.chronology()) { |
| return (R) IsoChronology.INSTANCE; |
| } else if (query == Queries.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()); |
| } |
| |
| } |