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 * However, the following notice accompanied the original version of this
 * file:
 *
 * Copyright (c) 2007-2012, Stephen Colebourne & Michael Nascimento Santos
 *
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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'.

 Month is an enum representing the 12 months of the year - January, February, March, April, May, June, July, August, September, October, November and December. 
 In addition to the textual enum name, each month-of-year has an int value. The 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 int value to ensure code clarity. 

Do not use ordinal() to obtain the numeric representation of Month. Use getValue() instead.


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.

Implementation Requirements:
This is an immutable and thread-safe enum.
Since:1.8
/**
 * 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 1. 
/**
     * 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 2. 
/**
     * 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 3. 
/**
     * 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 4. 
/**
     * 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 5. 
/**
     * 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 6. 
/**
     * 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 7. 
/**
     * 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 8. 
/**
     * 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 9. 
/**
     * 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 10. 
/**
     * 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 11. 
/**
     * 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 12. 
/**
     * 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 cache of all the constants.
     */
    private static final Month[] ENUMS = Month.values();

    //-----------------------------------------------------------------------
    
Obtains an instance of Month from an int value. 
 Month is an enum representing the 12 months of the year. This factory allows the enum to be obtained from the int value. The int value follows the ISO-8601 standard, from 1 (January) to 12 (December). 
Params:
  • month –  the month-of-year to represent, from 1 (January) to 12 (December)
Throws:
Returns:the month-of-year, not null
/**
     * 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 Month from a temporal object. 
 This obtains a month based on the specified temporal. A TemporalAccessor represents an arbitrary set of date and time information, which this factory converts to an instance of Month. 
 The conversion extracts the MONTH_OF_YEAR field. The extraction is only permitted if the temporal object has an ISO chronology, or can be converted to a LocalDate. 
 This method matches the signature of the functional interface TemporalQuery allowing it to be used as a query via method reference, Month::from. 
Params:
  • temporal –  the temporal object to convert, not null
Throws:
Returns:the month-of-year, not null
/**
     * 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 int value. 

The values are numbered following the ISO-8601 standard,
from 1 (January) to 12 (December).

Returns:the month-of-year, from 1 (January) to 12 (December)
/**
     * 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'.


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.

 If no textual mapping is found then the numeric value is returned. 
Params:
  • style –  the length of the text required, not null
  • locale –  the locale to use, not null
Returns:the text value of the month-of-year, not null
/**
     * 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.

 This checks if this month-of-year can be queried for the specified field. If false, then calling the range and get methods will throw an exception. 
 If the field is MONTH_OF_YEAR then this method returns true. All other ChronoField instances will return false. 
 If the field is not a ChronoField, then the result of this method is obtained by invoking TemporalField.isSupportedBy(TemporalAccessor) passing this as the argument. Whether the field is supported is determined by the field. 
Params:
  • field –  the field to check, null returns false
Returns:true if the field is supported on this month-of-year, false if not
/**
     * 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.


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.

 If the field is MONTH_OF_YEAR then the range of the month-of-year, from 1 to 12, will be returned. All other ChronoField instances will throw an UnsupportedTemporalTypeException. 
 If the field is not a ChronoField, then the result of this method is obtained by invoking TemporalField.rangeRefinedBy(TemporalAccessor) passing this as the argument. Whether the range can be obtained is determined by the field. 
Params:
  • field –  the field to query the range for, not null
Throws:
Returns:the range of valid values for the field, not null
/**
     * 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 int. 

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.

 If the field is MONTH_OF_YEAR then the value of the month-of-year, from 1 to 12, will be returned. All other ChronoField instances will throw an UnsupportedTemporalTypeException. 
 If the field is not a ChronoField, then the result of this method is obtained by invoking TemporalField.getFrom(TemporalAccessor) passing this as the argument. Whether the value can be obtained, and what the value represents, is determined by the field. 
Params:
  • field –  the field to get, not null
Throws:
Returns:the value for the field, within the valid range of values
/**
     * 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 long. 

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.

 If the field is MONTH_OF_YEAR then the value of the month-of-year, from 1 to 12, will be returned. All other ChronoField instances will throw an UnsupportedTemporalTypeException. 
 If the field is not a ChronoField, then the result of this method is obtained by invoking TemporalField.getFrom(TemporalAccessor) passing this as the argument. Whether the value can be obtained, and what the value represents, is determined by the field. 
Params:
  • field –  the field to get, not null
Throws:
Returns:the value for the 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.


The calculation rolls around the end of the year from December to January.
The specified period may be negative.


This instance is immutable and unaffected by this method call.

Params:
  • months –  the months to add, positive or negative
Returns:the resulting month, not null
/**
     * 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.


The calculation rolls around the start of the year from January to December.
The specified period may be negative.


This instance is immutable and unaffected by this method call.

Params:
  • months –  the months to subtract, positive or negative
Returns:the resulting month, not null
/**
     * 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.


This takes a flag to determine whether to return the length for a leap year or not.


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.

Params:
  • leapYear –  true if the length is required for a leap year
Returns:the length of this month in days, from 28 to 31
/**
     * 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.


February has a minimum length of 28 days.
April, June, September and November have 30 days.
All other months have 31 days.

Returns:the minimum length of this month in days, from 28 to 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.


February has a maximum length of 29 days.
April, June, September and November have 30 days.
All other months have 31 days.

Returns:the maximum length of this month in days, from 29 to 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.


This returns the day-of-year that this month begins on, using the leap
year flag to determine the length of February.

Params:
  • leapYear –  true if the length is required for a leap year
Returns:the day of year corresponding to the first day of this month, from 1 to 336
/**
     * 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.


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.

Returns:the first month of the quarter corresponding to this month, not null
/**
     * 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.

 This queries this month-of-year using the specified query strategy object. The 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. 
 The result of this method is obtained by invoking the TemporalQuery.queryFrom(TemporalAccessor) method on the specified query passing this as the argument. 
Params:
  • query –  the query to invoke, not null
Type parameters:
  • <R> – the type of the result
Throws:
Returns:the query result, null may be returned (defined by the query)
/**
     * 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.


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.

 The adjustment is equivalent to using Temporal.with(TemporalField, long) passing ChronoField.MONTH_OF_YEAR as the field. If the specified temporal object does not use the ISO calendar system then a DateTimeException is thrown. 
 In most cases, it is clearer to reverse the calling pattern by using Temporal.with(TemporalAdjuster): 
  // these two lines are equivalent, but the second approach is recommended
  temporal = thisMonth.adjustInto(temporal);
  temporal = temporal.with(thisMonth);




For example, given a date in May, the following are output:

  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




This instance is immutable and unaffected by this method call.

Params:
  • temporal –  the target object to be adjusted, not null
Throws:
Returns:the adjusted object, not null
/**
     * 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());
    }

}