Package org.apache.druid.segment

Class AbstractDimensionSelector

java.lang.Object

org.apache.druid.segment.AbstractDimensionSelector

All Implemented Interfaces:

HotLoopCallee, BaseDoubleColumnValueSelector, BaseFloatColumnValueSelector, BaseLongColumnValueSelector, BaseNullableColumnValueSelector, BaseObjectColumnValueSelector<Object>, ColumnValueSelector<Object>, DimensionDictionarySelector, DimensionSelector

Direct Known Subclasses:

PossiblyNullDimensionSelector

public abstract class AbstractDimensionSelector
extends Object
implements DimensionSelector

An abstract class that provides an implementation of getObject(). Don't extend this abstract class if you could provide a more efficient implementation for those methods, implement DimensionSelector directly then.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.druid.segment.DimensionSelector

DimensionSelector.NullDimensionSelectorHolder

Field Summary

Fields inherited from interface org.apache.druid.segment.ColumnValueSelector

EMPTY_ARRAY

Fields inherited from interface org.apache.druid.segment.DimensionDictionarySelector

CARDINALITY_UNKNOWN

Constructor Summary

Constructors

Constructor	Description
AbstractDimensionSelector()

Method Summary

Modifier and Type	Method	Description
Object	getObject()	Returns the currently-selected object.

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.segment.BaseObjectColumnValueSelector

classOfObject

Methods inherited from interface org.apache.druid.segment.DimensionDictionarySelector

getValueCardinality, idLookup, lookupName, lookupNameUtf8, nameLookupPossibleInAdvance, supportsLookupNameUtf8

Methods inherited from interface org.apache.druid.segment.DimensionSelector

defaultGetObject, getDouble, getFloat, getLong, getRow, isNull, makeValueMatcher, makeValueMatcher

Methods inherited from interface org.apache.druid.query.monomorphicprocessing.HotLoopCallee

inspectRuntimeShape

Constructor Detail

AbstractDimensionSelector

public AbstractDimensionSelector()

Method Detail

getObject

@Nullable
public Object getObject()

Description copied from interface: BaseObjectColumnValueSelector

Returns the currently-selected object. The behavior of this method depends on the type of selector, which can be determined by calling ColumnSelectorFactory.getColumnCapabilities(String) on the same ColumnSelectorFactory that you got this selector from. If the capabilties are nonnull, the selector type is given by TypeSignature.getType(). String selectors, where type is ColumnType.STRING, may return any type of object from this method, especially in cases where the selector is casting objects to string at selection time. Callers are encouraged to avoid the need to deal with various objects by using ColumnSelectorFactory.makeDimensionSelector(org.apache.druid.query.dimension.DimensionSpec) instead. Numeric selectors, where TypeSignature.isNumeric(), may return any type of Number. Callers that wish to deal with more specific types should treat the original ColumnValueSelector as a BaseLongColumnValueSelector, BaseDoubleColumnValueSelector, or BaseFloatColumnValueSelector instead. Array selectors, where TypeSignature.isArray(), must return Object[]. The array may contain null elements, and the array itself may also be null. Selectors of unknown type, where ColumnSelectorFactory.getColumnCapabilities(String) returns null, may return any type of object. Callers must be prepared for a wide variety of possible input objects. This case is common during ingestion, where selectors are built on top of external data.

Specified by:

getObject in interface BaseObjectColumnValueSelector<Object>