net.snowflake.common.core

Class CalendarCache

java.lang.Object

net.snowflake.common.core.CalendarCache

public class CalendarCache
extends Object

Created by mzukowski on 3/13/16. Implements a simple thread-local cache for GregorianCalendar objects. Note, by default it is not enabled, and will re-create the objects.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	CalendarCache.TimeZoneFactory TimeZone factory from which we get timezones.

Constructor Summary

Constructors

Constructor and Description
CalendarCache()

Method Summary

Modifier and Type	Method and Description
static GregorianCalendar	get(String tzId) Return a cached GregorianCalendar object.
static GregorianCalendar	get(TimeZone timezone) Return a cached GregorianCalendar object.
static GregorianCalendar	get(TimeZone timezone, String calId) Return a GregorianCalendar object identified by id.
static GregorianCalendar	get(TimeZone timezone, String tzId, String calId) Helper function.
static void	setAlwaysGregorian(boolean alwaysGregorian) Set if the the calendars produced should not observe Julian calendar before 1582.
static void	setEnabled(boolean enabled) Enable or disable the cache
static void	setProduceClones(boolean produceClones) Configure the CalendarCache to produce clones of cached objects (default behavior) or not.
static void	setTimeZoneFactory(CalendarCache.TimeZoneFactory tzFactory) Sets the timezone factory.

Methods inherited from class java.lang.Object

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

Constructor Detail

CalendarCache

public CalendarCache()

Method Detail

setEnabled

public static void setEnabled(boolean enabled)

Enable or disable the cache

Parameters:

enabled - true to enable cache or false

setProduceClones

public static void setProduceClones(boolean produceClones)

Configure the CalendarCache to produce clones of cached objects (default behavior) or not. It can be beneficial performance wise to not clone them, but it's possibly dangerous as _some_ operations using calendars (e.g. SimpleDateFormat) can modify the Calendar object.

Parameters:

produceClones - should it produce clones of cached objects.

setAlwaysGregorian

public static void setAlwaysGregorian(boolean alwaysGregorian)

Set if the the calendars produced should not observe Julian calendar before 1582. Calling this function also clears the cache.

setTimeZoneFactory

public static void setTimeZoneFactory(CalendarCache.TimeZoneFactory tzFactory)

Sets the timezone factory.

Parameters:

tzFactory - The TimeZoneFactory object to use, or null if the default timezone factory is to be used.

get

public static GregorianCalendar get(TimeZone timezone,
                                    String tzId,
                                    String calId)

Helper function. Returns a GregorianCalendar object.

Parameters:

timezone - Timezone to create the calendar in.

tzId - The id of the timezone (e.g. "America/Los_Angeles")

calId - Explicit ID of the calendar. Can be used e.g. if more than one copy of the calendar for the same timezone is needed. Note, if specified, the caller is responsible for making sure it's always the same timezone.

Returns:

The GregorianCalendar object. Note, it can be reused by other consumers, so be careful changing any settings in it

get

public static GregorianCalendar get(TimeZone timezone,
                                    String calId)

Return a GregorianCalendar object identified by id. If caching is enabled and an object with the same id existed, it will be returned, otherwise a new object will be created.

Parameters:

timezone - Timezone to create the calendar in

calId - Explicit ID of the calendar. Can be used e.g. if more than one copy of the calendar for the same timezone is needed. Note, if specified, the caller is responsible for making sure it's always the same timezone.

Returns:

The GregorianCalendar object. Note, it can be reused by other consumers, so be careful changing any settings in it

get

public static GregorianCalendar get(TimeZone timezone)

Return a cached GregorianCalendar object. If doesn't exist, will be created.

Parameters:

timezone - Timezone to create the calendar in

Returns:

The GregorianCalendar object. Note, it can be reused by other consumers, so do not change any non-basic settings in it (like date).

get

public static GregorianCalendar get(String tzId)

Return a cached GregorianCalendar object. If doesn't exist, will be created.

Parameters:

tzId - The id of the timezone (e.g. "America/Los_Angeles")

Returns:

The GregorianCalendar object. Note, it can be reused by other consumers, so do not change any non-basic settings in it (like date).