edu.princeton.cs.algorithms

Class Date

java.lang.Object

edu.princeton.cs.algorithms.Date

All Implemented Interfaces:

Comparable<Date>

public class Date
extends Object
implements Comparable<Date>

The Date class is an immutable data type to encapsulate a date (day, month, and year).

For additional documentation, see Section 1.2 of Algorithms, 4th Edition by Robert Sedgewick and Kevin Wayne.

Author:

Robert Sedgewick, Kevin Wayne

Constructor Summary

Constructors

Constructor and Description
Date(int month, int day, int year) Initializes a new date from the month, day, and year.
Date(String date) Initializes new date specified as a string in form MM/DD/YYYY.

Method Summary

Methods

Modifier and Type	Method and Description
int	compareTo(Date that) Compare this date to that date.
int	day() Return the day.
boolean	equals(Object x) Is this date equal to x?
int	hashCode() Return a hash code.
boolean	isAfter(Date b) Is this date after b?
boolean	isBefore(Date b) Is this date before b?
static void	main(String[] args) Unit tests the date data type.
int	month() Return the month.
Date	next() Returns the next date in the calendar.
String	toString() Return a string representation of this date.
int	year() Return the year.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

Date

public Date(int month,
    int day,
    int year)

Initializes a new date from the month, day, and year.

Parameters:

month - the month (between 1 and 12)

day - the day (between 1 and 28-31, depending on the month)

year - the year

Throws:

IllegalArgumentException - if the date is invalid

Date

public Date(String date)

Initializes new date specified as a string in form MM/DD/YYYY.

Parameters:

date - the string representation of the date

Throws:

IllegalArgumentException - if the date is invalid

Method Detail

month

public int month()

Return the month.

Returns:

the month (an integer between 1 and 12)

day

public int day()

Return the day.

Returns:

the day (an integer between 1 and 31)

year

public int year()

Return the year.

Returns:

the year

next

public Date next()

Returns the next date in the calendar.

Returns:

a date that represents the next day after this day

isAfter

public boolean isAfter(Date b)

Is this date after b?

Returns:

true if this date is after date b; false otherwise

isBefore

public boolean isBefore(Date b)

Is this date before b?

Returns:

true if this date is before date b; false otherwise

compareTo

public int compareTo(Date that)

Compare this date to that date.

Specified by:

compareTo in interface Comparable<Date>

Returns:

{ a negative integer, zero, or a positive integer }, depending on whether this date is { before, equal to, after } that date

toString

public String toString()

Return a string representation of this date.

Overrides:

toString in class Object

Returns:

the string representation in the foramt MM/DD/YYYY

equals

public boolean equals(Object x)

Is this date equal to x?

Overrides:

equals in class Object

Returns:

true if this date equals x; false otherwise

hashCode

public int hashCode()

Return a hash code.

Overrides:

hashCode in class Object

Returns:

a hash code for this date

main

public static void main(String[] args)

Unit tests the date data type.