org.jfree.data.time

Class RegularTimePeriod

Implemented Interfaces:
Comparable, MonthConstants, TimePeriod
Known Direct Subclasses:
Day, FixedMillisecond, Hour, Millisecond, Minute, Month, Quarter, Second, Week, Year

public abstract class RegularTimePeriod
extends java.lang.Object
implements TimePeriod, Comparable, MonthConstants

An abstract class representing a unit of time. Convenient methods are provided for calculating the next and previous time periods. Conversion methods are defined that return the first and last milliseconds of the time period. The results from these methods are timezone dependent.

This class is immutable, and all subclasses should be immutable also.

Field Summary

static TimeZone
DEFAULT_TIME_ZONE
The default time zone.
static Calendar
WORKING_CALENDAR
A working calendar (recycle to avoid unnecessary object creation).

Method Summary

static RegularTimePeriod
createInstance(Class c, Date millisecond, TimeZone zone)
Creates a time period that includes the specified millisecond, assuming the given time zone.
static Class
downsize(Class c)
Returns a subclass of RegularTimePeriod that is smaller than the specified class.
Date
getEnd()
Returns the date/time that marks the end of the time period.
long
getFirstMillisecond()
Returns the first millisecond of the time period, evaluated in the default time zone.
abstract long
getFirstMillisecond(Calendar calendar)
Returns the first millisecond of the time period, evaluated using the supplied calendar (which incorporates a timezone).
long
getFirstMillisecond(TimeZone zone)
Returns the first millisecond of the time period, evaluated within a specific time zone.
long
getLastMillisecond()
Returns the last millisecond of the time period, evaluated in the default time zone.
abstract long
getLastMillisecond(Calendar calendar)
Returns the last millisecond of the time period, evaluated using the supplied calendar (which incorporates a timezone).
long
getLastMillisecond(TimeZone zone)
Returns the last millisecond of the time period, evaluated within a specific time zone.
long
getMiddleMillisecond()
Returns the millisecond closest to the middle of the time period, evaluated in the default time zone.
long
getMiddleMillisecond(Calendar calendar)
Returns the millisecond closest to the middle of the time period, evaluated using the supplied calendar (which incorporates a timezone).
long
getMiddleMillisecond(TimeZone zone)
Returns the millisecond closest to the middle of the time period, evaluated within a specific time zone.
abstract long
getSerialIndex()
Returns a serial index number for the time unit.
Date
getStart()
Returns the date/time that marks the start of the time period.
abstract RegularTimePeriod
next()
Returns the time period following this one, or null if some limit has been reached.
abstract RegularTimePeriod
previous()
Returns the time period preceding this one, or null if some lower limit has been reached.
String
toString()
Returns a string representation of the time period.

Field Details

DEFAULT_TIME_ZONE

public static final TimeZone DEFAULT_TIME_ZONE
The default time zone.

WORKING_CALENDAR

public static final Calendar WORKING_CALENDAR
A working calendar (recycle to avoid unnecessary object creation).

Method Details

createInstance

public static RegularTimePeriod createInstance(Class c,
                                               Date millisecond,
                                               TimeZone zone)
Creates a time period that includes the specified millisecond, assuming the given time zone.
Parameters:
c - the time period class.
millisecond - the time.
zone - the time zone.
Returns:
The time period.

downsize

public static Class downsize(Class c)
Returns a subclass of RegularTimePeriod that is smaller than the specified class.
Parameters:
c - a subclass of RegularTimePeriod.
Returns:
A class.

getEnd

public Date getEnd()
Returns the date/time that marks the end of the time period.
Specified by:
getEnd in interface TimePeriod
Returns:
The end date/time.

getFirstMillisecond

public long getFirstMillisecond()
Returns the first millisecond of the time period, evaluated in the default time zone.
Returns:
The first millisecond of the time period.

getFirstMillisecond

public abstract long getFirstMillisecond(Calendar calendar)
Returns the first millisecond of the time period, evaluated using the supplied calendar (which incorporates a timezone).
Parameters:
calendar - the calendar.
Returns:
The first millisecond of the time period.

getFirstMillisecond

public long getFirstMillisecond(TimeZone zone)
Returns the first millisecond of the time period, evaluated within a specific time zone.
Parameters:
zone - the time zone.
Returns:
The first millisecond of the time period.

getLastMillisecond

public long getLastMillisecond()
Returns the last millisecond of the time period, evaluated in the default time zone.
Returns:
The last millisecond of the time period.

getLastMillisecond

public abstract long getLastMillisecond(Calendar calendar)
Returns the last millisecond of the time period, evaluated using the supplied calendar (which incorporates a timezone).
Parameters:
calendar - the calendar.
Returns:
The last millisecond of the time period.

getLastMillisecond

public long getLastMillisecond(TimeZone zone)
Returns the last millisecond of the time period, evaluated within a specific time zone.
Parameters:
zone - the time zone.
Returns:
The last millisecond of the time period.

getMiddleMillisecond

public long getMiddleMillisecond()
Returns the millisecond closest to the middle of the time period, evaluated in the default time zone.
Returns:
The middle millisecond.

getMiddleMillisecond

public long getMiddleMillisecond(Calendar calendar)
Returns the millisecond closest to the middle of the time period, evaluated using the supplied calendar (which incorporates a timezone).
Parameters:
calendar - the calendar.
Returns:
The middle millisecond.

getMiddleMillisecond

public long getMiddleMillisecond(TimeZone zone)
Returns the millisecond closest to the middle of the time period, evaluated within a specific time zone.
Parameters:
zone - the time zone.
Returns:
The middle millisecond.

getSerialIndex

public abstract long getSerialIndex()
Returns a serial index number for the time unit.
Returns:
The serial index number.

getStart

public Date getStart()
Returns the date/time that marks the start of the time period.
Specified by:
getStart in interface TimePeriod
Returns:
The start date/time.

next

public abstract RegularTimePeriod next()
Returns the time period following this one, or null if some limit has been reached.
Returns:
The next time period (possibly null).

previous

public abstract RegularTimePeriod previous()
Returns the time period preceding this one, or null if some lower limit has been reached.
Returns:
The previous time period (possibly null).

toString

public String toString()
Returns a string representation of the time period.
Returns:
The string.