Package com.illumon.iris.db.v2.by

Class MinMaxByStateFactoryImpl

java.lang.Object

com.illumon.iris.db.v2.by.ReaggregatableStatefactory

com.illumon.iris.db.v2.by.MinMaxByStateFactoryImpl

All Implemented Interfaces:

BasicDeflatable<MinMaxByStateFactoryImpl>, AggregationStateFactory

Direct Known Subclasses:

AppendMinMaxByStateFactoryImpl

public class MinMaxByStateFactoryImpl
extends ReaggregatableStatefactory
implements BasicDeflatable<MinMaxByStateFactoryImpl>

Minimum and Maximum aggregation factory. Operates in two modes, for non-refreshing tables it requires very little state (just the current minimum or maximum). For refreshing tables, it requires maintaining a TreeMap of values to counts; so that if the min/max value is removed we are able to identify the next lowest/highest value. You can use AppendMinMaxByStateFactoryImpl if you want to force append-only behavior.

Constructor Summary

Constructors

Constructor	Description
MinMaxByStateFactoryImpl(boolean minimum)	Create a minBy or maxBy factory.

Method Summary

Modifier and Type	Method	Description
BasicInflatable<MinMaxByStateFactoryImpl>	deflate()
AggregationMemoKey	getMemoKey()	Produces a MemoKey for this aggregation state factory.
boolean	isMinimum()
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Details

MinMaxByStateFactoryImpl

public MinMaxByStateFactoryImpl(boolean minimum)

Create a minBy or maxBy factory.

Parameters:

minimum - true if selecting the minimum value, false if selecting the maximum value.

Method Details

isMinimum

public boolean isMinimum()

getMemoKey

public AggregationMemoKey getMemoKey()

Description copied from interface: AggregationStateFactory

Produces a MemoKey for this aggregation state factory.

If two AggregationStateFactories have equal memoKeys, then Table.by(com.illumon.iris.db.v2.by.AggregationStateFactory, com.illumon.iris.db.v2.select.SelectColumn...) operations that have the same group by columns may be memoized. In that case instead of recomputing the result; the original result will be used.

If null is returned, the operation will not be memoized.

Specified by:

getMemoKey in interface AggregationStateFactory

Returns:

an AggregationMemoKey, null if this operation can not be memoized.

deflate

public BasicInflatable<MinMaxByStateFactoryImpl> deflate()

Specified by:

deflate in interface BasicDeflatable<MinMaxByStateFactoryImpl>

toString

public String toString()

Overrides:

toString in class Object