org.jfree.data.time

Class Month

Implemented Interfaces:
Comparable, MonthConstants, Serializable, TimePeriod

public class Month
extends RegularTimePeriod
implements Serializable

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

Field Summary

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

DEFAULT_TIME_ZONE, WORKING_CALENDAR

Constructor Summary

Month()
Constructs a new Month, based on the current system time.
Month(Date time)
Constructs a new Month instance, based on a date/time and the default time zone.
Month(Date time, TimeZone zone)
Constructs a new Month instance, based on a date/time and a time zone.
Month(int month, int year)
Constructs a new month instance.
Month(int month, Year year)
Constructs a new month instance.

Method Summary

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, getEnd, getFirstMillisecond, getFirstMillisecond, getFirstMillisecond, getLastMillisecond, getLastMillisecond, getLastMillisecond, getMiddleMillisecond, getMiddleMillisecond, getMiddleMillisecond, getSerialIndex, getStart, next, peg, previous, toString

Constructor Details

Month

public Month()
Constructs a new Month, based on the current system time.

Month

public Month(Date time)
Constructs a new Month instance, based on a date/time and the default time zone.
Parameters:
time - the date/time.

Month

public Month(Date time,
             TimeZone zone)
Constructs a new Month instance, based on a date/time and a time zone. The first and last millisecond values are initially pegged to the given time zone also.
Parameters:
time - the date/time.
zone - the time zone (null not permitted).

Month

public Month(int month,
             int year)
Constructs a new month instance.
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.
Parameters:
month - the month (in the range 1 to 12).
year - the year.

Method Details

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.
Parameters:
o1 - the object to compare.
Returns:
negative == before, zero == same, positive == after.

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.
Parameters:
obj - the object (null permitted).
Returns:
true if month and year of this and object are the same.

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.
Overrides:
getFirstMillisecond in interface RegularTimePeriod
Returns:
The first millisecond of the month.

getFirstMillisecond

public long getFirstMillisecond(Calendar calendar)
Returns the first millisecond of the month, evaluated using the supplied calendar (which determines the time zone).
Overrides:
getFirstMillisecond in interface RegularTimePeriod
Parameters:
calendar - the calendar (null not permitted).
Returns:
The first millisecond of the month.

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.
Overrides:
getLastMillisecond in interface RegularTimePeriod
Returns:
The last millisecond of the month.

getLastMillisecond

public long getLastMillisecond(Calendar calendar)
Returns the last millisecond of the month, evaluated using the supplied calendar (which determines the time zone).
Overrides:
getLastMillisecond in interface RegularTimePeriod
Parameters:
calendar - the calendar (null not permitted).
Returns:
The last millisecond of the month.

getMonth

public int getMonth()
Returns the month. Note that 1=JAN, 2=FEB, ...
Returns:
The month.

getSerialIndex

public long getSerialIndex()
Returns a serial index number for the month.
Overrides:
getSerialIndex in interface RegularTimePeriod
Returns:
The serial index number.

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).

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

Returns:
A hash code.

next

public RegularTimePeriod next()
Returns the month following this one.
Overrides:
next in interface RegularTimePeriod
Returns:
The month following this one.

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

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).
Overrides:
peg in interface RegularTimePeriod
Parameters:
calendar - the calendar (null not permitted).
Since:
1.0.3

previous

public RegularTimePeriod previous()
Returns the month preceding this one.
Overrides:
previous in interface RegularTimePeriod
Returns:
The month preceding this one.

toString

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

To do: look at internationalisation.

Overrides:
toString in interface RegularTimePeriod
Returns:
A string representing the month.