Package org.apache.druid.java.util.common.granularity

Class Granularity

java.lang.Object

org.apache.druid.java.util.common.granularity.Granularity

All Implemented Interfaces:

Cacheable

Direct Known Subclasses:

AllGranularity, DurationGranularity, NoneGranularity, PeriodGranularity

public abstract class Granularity
extends Object
implements Cacheable

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Granularity.Formatter

Field Summary

Fields

Modifier and Type	Field	Description
static Comparator<Granularity>	IS_FINER_THAN

Constructor Summary

Constructors

Constructor	Description
Granularity()

Method Summary

Modifier and Type	Method	Description
org.joda.time.Interval	bucket(org.joda.time.DateTime t)	Return a granularity-sized Interval containing a particular DateTime.
org.joda.time.DateTime	bucketEnd(org.joda.time.DateTime time)
abstract long	bucketStart(long time)
abstract org.joda.time.DateTime	bucketStart(org.joda.time.DateTime time)
static Granularity	fromString(String str)
abstract org.joda.time.format.DateTimeFormatter	getFormatter(Granularity.Formatter type)
Iterable<org.joda.time.Interval>	getIterable(org.joda.time.Interval input)	Return an iterable of granular buckets that overlap a particular interval.
org.joda.time.DateTimeZone	getTimeZone()
static List<Granularity>	granularitiesFinerThan(Granularity gran0)	Returns a list of standard granularities that are equal to, or finer than, a provided granularity.
abstract long	increment(long time)
abstract org.joda.time.DateTime	increment(org.joda.time.DateTime time)
abstract boolean	isAligned(org.joda.time.Interval interval)	Return true only if the time chunks populated by this granularity includes the given interval time chunk.
boolean	isFinerThan(Granularity g)	Decides whether this granularity is finer than the other granularity
static Granularity	mergeGranularities(List<Granularity> toMerge)	simple merge strategy on query granularity that checks if all are equal or else returns null.
org.joda.time.DateTime	toDate(String filePath)
abstract org.joda.time.DateTime	toDate(String filePath, Granularity.Formatter formatter)
org.joda.time.DateTime	toDateTime(long offset)
String	toPath(org.joda.time.DateTime time)

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.apache.druid.java.util.common.Cacheable

getCacheKey

Field Detail

IS_FINER_THAN

public static final Comparator<Granularity> IS_FINER_THAN

Constructor Detail

Granularity

public Granularity()

Method Detail

fromString

public static Granularity fromString(String str)

mergeGranularities

public static Granularity mergeGranularities(List<Granularity> toMerge)

simple merge strategy on query granularity that checks if all are equal or else returns null. this can be improved in future but is good enough for most use-cases.

granularitiesFinerThan

public static List<Granularity> granularitiesFinerThan(Granularity gran0)

Returns a list of standard granularities that are equal to, or finer than, a provided granularity. ALL will not be returned unless the provided granularity is ALL. NONE will never be returned, even if the provided granularity is NONE. This is because the main usage of this function in production is segment allocation, and we do not wish to generate NONE-granular segments.

getFormatter

public abstract org.joda.time.format.DateTimeFormatter getFormatter(Granularity.Formatter type)

increment

public abstract long increment(long time)

increment

public abstract org.joda.time.DateTime increment(org.joda.time.DateTime time)

bucketStart

public abstract long bucketStart(long time)

bucketStart

public abstract org.joda.time.DateTime bucketStart(org.joda.time.DateTime time)

toDate

public abstract org.joda.time.DateTime toDate(String filePath,
                                              Granularity.Formatter formatter)

isAligned

public abstract boolean isAligned(org.joda.time.Interval interval)

Return true only if the time chunks populated by this granularity includes the given interval time chunk. The interval must fit exactly into the scheme of the granularity for this to return true

getTimeZone

public org.joda.time.DateTimeZone getTimeZone()

bucketEnd

public org.joda.time.DateTime bucketEnd(org.joda.time.DateTime time)

toDateTime

public org.joda.time.DateTime toDateTime(long offset)

toDate

public org.joda.time.DateTime toDate(String filePath)

toPath

public final String toPath(org.joda.time.DateTime time)

bucket

public final org.joda.time.Interval bucket(org.joda.time.DateTime t)

Return a granularity-sized Interval containing a particular DateTime.

isFinerThan

public boolean isFinerThan(Granularity g)

Decides whether this granularity is finer than the other granularity

Returns:

true if this Granularity is finer than the passed one

getIterable

public Iterable<org.joda.time.Interval> getIterable(org.joda.time.Interval input)

Return an iterable of granular buckets that overlap a particular interval. In cases where the number of granular buckets is very large, the Iterable returned by this method will take an excessive amount of time to compute, and materializing it into a collection will take an excessive amount of memory. For example, this happens in the extreme case of an input interval of Intervals.ETERNITY and any granularity other than Granularities.ALL, as well as cases like an input interval of ten years with Granularities.SECOND. To avoid issues stemming from large numbers of buckets, this method should be avoided, and code that uses this method should be rewritten to use some other approach. For example: rather than computing all possible buckets in a wide time range, only process buckets related to actual data points that appear.