Module org.jfree.chart

Package org.jfree.data.time

Class Month

java.lang.Object

org.jfree.data.time.RegularTimePeriod

org.jfree.data.time.Month

All Implemented Interfaces:

Serializable, Comparable, MonthConstants, TimePeriod

public class Month
extends RegularTimePeriod
implements Serializable

Represents a single month. This class is immutable, which is a requirement for all RegularTimePeriod subclasses.

See Also:

Serialized Form

Field Summary

Fields inherited from interface org.jfree.chart.date.MonthConstants

APRIL, AUGUST, DECEMBER, FEBRUARY, JANUARY, JULY, JUNE, MARCH, MAY, NOVEMBER, OCTOBER, SEPTEMBER

Constructor Summary

Constructors

Constructor	Description
Month()	Constructs a new Month, based on the current system time.
Month(int month, int year)	Constructs a new month instance.
Month(int month, Year year)	Constructs a new month instance.
Month(Date time)	Constructs a new Month instance, based on a date/time.
Month(Date time, Calendar calendar)	Constructs a new instance, based on a particular date/time.
Month(Date time, TimeZone zone, Locale locale)	Creates a new Month instance, based on the specified time, zone and locale.

Method Summary

Modifier and Type	Method	Description
int	compareTo(Object o1)	Returns an integer indicating the order of this Month object relative to the specified object: negative == before, zero == same, positive == after.
boolean	equals(Object obj)	Tests the equality of this Month object to an arbitrary object.
long	getFirstMillisecond()	Returns the first millisecond of the month.
long	getFirstMillisecond(Calendar calendar)	Returns the first millisecond of the month, evaluated using the supplied calendar (which determines the time zone).
long	getLastMillisecond()	Returns the last millisecond of the month.
long	getLastMillisecond(Calendar calendar)	Returns the last millisecond of the month, evaluated using the supplied calendar (which determines the time zone).
int	getMonth()	Returns the month.
long	getSerialIndex()	Returns a serial index number for the month.
Year	getYear()	Returns the year in which the month falls.
int	getYearValue()	Returns the year in which the month falls.
int	hashCode()	Returns a hash code for this object instance.
RegularTimePeriod	next()	Returns the month following this one.
static Month	parseMonth(String s)	Parses the string argument as a month.
void	peg(Calendar calendar)	Recalculates the start date/time and end date/time for this time period relative to the supplied calendar (which incorporates a time zone).
RegularTimePeriod	previous()	Returns the month preceding this one.
String	toString()	Returns a string representing the month (e.g.

Methods inherited from class org.jfree.data.time.RegularTimePeriod

createInstance, downsize, getCalendarInstance, getEnd, getMiddleMillisecond, getMiddleMillisecond, getMillisecond, getStart, setCalendarInstancePrototype, setThreadLocalCalendarInstance

Methods inherited from class java.lang.Object

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

Constructor Detail

Month

public Month()

Constructs a new Month, based on the current system time. The time zone and locale are determined by the calendar returned by RegularTimePeriod.getCalendarInstance().

Month

public Month(int month,
             int year)

Constructs a new month instance. The time zone and locale are determined by the calendar returned by RegularTimePeriod.getCalendarInstance().

Parameters:

month - the month (in the range 1 to 12).

year - the year.

Month

public Month(int month,
             Year year)

Constructs a new month instance. The time zone and locale are determined by the calendar returned by RegularTimePeriod.getCalendarInstance().

Parameters:

month - the month (in the range 1 to 12).

year - the year.

Month

public Month(Date time)

Constructs a new Month instance, based on a date/time. The time zone and locale are determined by the calendar returned by RegularTimePeriod.getCalendarInstance().

Parameters:

time - the date/time (null not permitted).

See Also:

Month(Date, TimeZone, Locale)

Month

public Month(Date time,
             TimeZone zone,
             Locale locale)

Creates a new Month instance, based on the specified time, zone and locale.

Parameters:

time - the current time.

zone - the time zone.

locale - the locale.

Since:

1.0.12

Month

public Month(Date time,
             Calendar calendar)

Constructs a new instance, based on a particular date/time. The time zone and locale are determined by the calendar parameter.

Parameters:

time - the date/time (null not permitted).

calendar - the calendar to use for calculations (null not permitted).

Method Detail

getYear

public Year getYear()

Returns the year in which the month falls.

Returns:

The year in which the month falls (as a Year object).

getYearValue

public int getYearValue()

Returns the year in which the month falls.

Returns:

The year in which the month falls (as an int).

getMonth

public int getMonth()

Returns the month. Note that 1=JAN, 2=FEB, ...

Returns:

The month.

getFirstMillisecond

public long getFirstMillisecond()

Returns the first millisecond of the month. This will be determined relative to the time zone specified in the constructor, or in the calendar instance passed in the most recent call to the peg(Calendar) method.

Specified by:

getFirstMillisecond in class RegularTimePeriod

Returns:

The first millisecond of the month.

See Also:

getLastMillisecond()

getLastMillisecond

public long getLastMillisecond()

Returns the last millisecond of the month. This will be determined relative to the time zone specified in the constructor, or in the calendar instance passed in the most recent call to the peg(Calendar) method.

Specified by:

getLastMillisecond in class RegularTimePeriod

Returns:

The last millisecond of the month.

See Also:

getFirstMillisecond()

peg

public void peg(Calendar calendar)

Recalculates the start date/time and end date/time for this time period relative to the supplied calendar (which incorporates a time zone).

Specified by:

peg in class RegularTimePeriod

Parameters:

calendar - the calendar (null not permitted).

Since:

1.0.3

previous

public RegularTimePeriod previous()

Returns the month preceding this one. Note that the returned Month is "pegged" using the default calendar, obtained with RegularTimePeriod.getCalendarInstance(), irrespective of the time-zone used to peg of the current month (which is not recorded anywhere). See the peg(Calendar) method.

Specified by:

previous in class RegularTimePeriod

Returns:

The month preceding this one.

next

public RegularTimePeriod next()

Returns the month following this one. Note that the returned Month is "pegged" using the default calendar, obtained with RegularTimePeriod.getCalendarInstance(), irrespective of the time-zone used to peg of the current month (which is not recorded anywhere). See the peg(Calendar) method.

Specified by:

next in class RegularTimePeriod

Returns:

The month following this one.

getSerialIndex

public long getSerialIndex()

Returns a serial index number for the month.

Specified by:

getSerialIndex in class RegularTimePeriod

Returns:

The serial index number.

toString

public String toString()

Returns a string representing the month (e.g. "January 2002").

To do: look at internationalisation.

Overrides:

toString in class RegularTimePeriod

Returns:

A string representing the month.

equals

public boolean equals(Object obj)

Tests the equality of this Month object to an arbitrary object. Returns true if the target is a Month instance representing the same month as this object. In all other cases, returns false.

Overrides:

equals in class Object

Parameters:

obj - the object (null permitted).

Returns:

true if month and year of this and object are the same.

hashCode

public int hashCode()

Returns a hash code for this object instance. The approach described by Joshua Bloch in "Effective Java" has been used here:

http://developer.java.sun.com/developer/Books/effectivejava /Chapter3.pdf

Overrides:

hashCode in class Object

Returns:

A hash code.

compareTo

public int compareTo(Object o1)

Returns an integer indicating the order of this Month object relative to the specified object: negative == before, zero == same, positive == after.

Specified by:

compareTo in interface Comparable

Parameters:

o1 - the object to compare.

Returns:

negative == before, zero == same, positive == after.

getFirstMillisecond

public long getFirstMillisecond(Calendar calendar)

Returns the first millisecond of the month, evaluated using the supplied calendar (which determines the time zone).

Specified by:

getFirstMillisecond in class RegularTimePeriod

Parameters:

calendar - the calendar (null not permitted).

Returns:

The first millisecond of the month.

Throws:

NullPointerException - if calendar is null.

See Also:

RegularTimePeriod.getLastMillisecond(Calendar)

getLastMillisecond

public long getLastMillisecond(Calendar calendar)

Returns the last millisecond of the month, evaluated using the supplied calendar (which determines the time zone).

Specified by:

getLastMillisecond in class RegularTimePeriod

Parameters:

calendar - the calendar (null not permitted).

Returns:

The last millisecond of the month.

Throws:

NullPointerException - if calendar is null.

See Also:

RegularTimePeriod.getFirstMillisecond(Calendar)

parseMonth

public static Month parseMonth(String s)

Parses the string argument as a month. This method is required to accept the format "YYYY-MM". It will also accept "MM-YYYY". Anything else, at the moment, is a bonus.

Parameters:

s - the string to parse (null permitted).

Returns:

null if the string is not parseable, the month otherwise.