horstmann.ch03_day1

Class Day

java.lang.Object

horstmann.ch03_day1.Day

public class Day
extends java.lang.Object

Field Summary

Fields

Modifier and Type	Field and Description
private int	date
private static int[]	DAYS_PER_MONTH
private static int	DECEMBER
private static int	FEBRUARY
private static int	GREGORIAN_START_DAY
private static int	GREGORIAN_START_MONTH
private static int	GREGORIAN_START_YEAR
private static int	JANUARY
private static int	JULIAN_END_DAY
private int	month
private int	year

Constructor Summary

Constructors

Constructor and Description
Day(int aYear, int aMonth, int aDate) Constructs a day with a given year, month, and day of the Julian/Gregorian calendar.

Method Summary

Modifier and Type	Method and Description
Day	addDays(int n) Returns a day that is a certain number of days away from this day
private int	compareTo(Day other) Compares this day with another day.
int	daysFrom(Day other) Returns the number of days between this day and another day
private static int	daysPerMonth(int y, int m) Gets the days in a given month
int	getDate() Returns the day of the month of this day
int	getMonth() Returns the month of this day
int	getYear() Returns the year of this day
private static boolean	isLeapYear(int y) Tests if a year is a leap year
private Day	nextDay() Computes the next day.
private Day	previousDay() Computes the previous day.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

year

private int year

month

private int month

date

private int date

DAYS_PER_MONTH

private static final int[] DAYS_PER_MONTH

GREGORIAN_START_YEAR

private static final int GREGORIAN_START_YEAR

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Constant Field Values

GREGORIAN_START_MONTH

private static final int GREGORIAN_START_MONTH

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Constant Field Values

GREGORIAN_START_DAY

private static final int GREGORIAN_START_DAY

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Constant Field Values

JULIAN_END_DAY

private static final int JULIAN_END_DAY

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Constant Field Values

JANUARY

private static final int JANUARY

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Constant Field Values

FEBRUARY

private static final int FEBRUARY

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Constant Field Values

DECEMBER

private static final int DECEMBER

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Constant Field Values

Constructor Detail

Day

public Day(int aYear,
           int aMonth,
           int aDate)

Constructs a day with a given year, month, and day of the Julian/Gregorian calendar. The Julian calendar is used for all days before October 15, 1582

Parameters:

aYear - a year != 0

aMonth - a month between 1 and 12

aDate - a date between 1 and 31

Method Detail

getYear

public int getYear()

Returns the year of this day

Returns:

the year

getMonth

public int getMonth()

Returns the month of this day

Returns:

the month

getDate

public int getDate()

Returns the day of the month of this day

Returns:

the day of the month

addDays

public Day addDays(int n)

Returns a day that is a certain number of days away from this day

Parameters:

n - the number of days, can be negative

Returns:

a day that is n days away from this one

daysFrom

public int daysFrom(Day other)

Returns the number of days between this day and another day

Parameters:

other - the other day

Returns:

the number of days that this day is away from the other (>0 if this day comes later)

compareTo

private int compareTo(Day other)

Compares this day with another day.

Parameters:

other - the other day

Returns:

a positive number if this day comes after the other day, a negative number if this day comes before the other day, and zero if the days are the same

nextDay

private Day nextDay()

Computes the next day.

Returns:

the day following this day

previousDay

private Day previousDay()

Computes the previous day.

Returns:

the day preceding this day

daysPerMonth

private static int daysPerMonth(int y,
                                int m)

Gets the days in a given month

Parameters:

y - the year

m - the month

Returns:

the last day in the given month

isLeapYear

private static boolean isLeapYear(int y)

Tests if a year is a leap year

Parameters:

y - the year

Returns:

true if y is a leap year