org.apache.druid.segment.virtual

Class BaseExpressionColumnValueSelector

java.lang.Object

org.apache.druid.segment.virtual.BaseExpressionColumnValueSelector

All Implemented Interfaces:

HotLoopCallee, BaseDoubleColumnValueSelector, BaseFloatColumnValueSelector, BaseLongColumnValueSelector, BaseNullableColumnValueSelector, BaseObjectColumnValueSelector<ExprEval>, ColumnValueSelector<ExprEval>

Direct Known Subclasses:

ExpressionColumnValueSelector, RowBasedExpressionColumnValueSelector, SingleLongInputCachingExpressionColumnValueSelector, SingleStringInputCachingExpressionColumnValueSelector

public abstract class BaseExpressionColumnValueSelector
extends Object
implements ColumnValueSelector<ExprEval>

Base class for many (although not all) ColumnValueSelector<ExprEval>.

Field Summary

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

EMPTY_ARRAY

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	BaseExpressionColumnValueSelector(RowIdSupplier rowIdSupplier)

Method Summary

Modifier and Type	Method and Description
Class<ExprEval>	classOfObject()
protected abstract ExprEval<?>	eval() Implementations override this.
double	getDouble()
float	getFloat()
long	getLong()
ExprEval<?>	getObject()
void	inspectRuntimeShape(RuntimeShapeInspector inspector) Implementations of this method should call inspector.visit() with all fields of this class, which meet two conditions: 1.
boolean	isNull() Returns true if the primitive long, double, or float value returned by this selector should be treated as null.

Methods inherited from class java.lang.Object

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

Constructor Detail

BaseExpressionColumnValueSelector

protected BaseExpressionColumnValueSelector(@Nullable
                                            RowIdSupplier rowIdSupplier)

Method Detail

getDouble

public double getDouble()

Specified by:

getDouble in interface BaseDoubleColumnValueSelector

getFloat

public float getFloat()

Specified by:

getFloat in interface BaseFloatColumnValueSelector

getLong

public long getLong()

Specified by:

getLong in interface BaseLongColumnValueSelector

isNull

public boolean isNull()

Description copied from interface: BaseNullableColumnValueSelector

Returns true if the primitive long, double, or float value returned by this selector should be treated as null. Users of BaseLongColumnValueSelector.getLong(), BaseDoubleColumnValueSelector.getDouble() and BaseFloatColumnValueSelector.getFloat() must check this method first, or else they may improperly use placeholder values returned by the primitive get methods. Users of BaseObjectColumnValueSelector.getObject() should not call this method. Instead, call "getObject" and check if it is null.

Specified by:

isNull in interface BaseNullableColumnValueSelector

getObject

@Nullable
public ExprEval<?> getObject()

Specified by:

getObject in interface BaseObjectColumnValueSelector<ExprEval>

classOfObject

public Class<ExprEval> classOfObject()

Specified by:

classOfObject in interface BaseObjectColumnValueSelector<ExprEval>

inspectRuntimeShape

public void inspectRuntimeShape(RuntimeShapeInspector inspector)

Description copied from interface: HotLoopCallee

Implementations of this method should call inspector.visit() with all fields of this class, which meet two conditions: 1. They are used in methods of this class, annotated with CalledFromHotLoop 2. They are either: a. Nullable objects b. Instances of HotLoopCallee c. Objects, which don't always have a specific class in runtime. For example, a field of type Set could be HashSet or TreeSet in runtime, depending on how this instance (the instance on which inspectRuntimeShape() is called) is configured. d. ByteBuffer or similar objects, where byte order matters e. boolean flags, affecting branch taking f. Arrays of objects, meeting any of conditions a-e.

Specified by:

inspectRuntimeShape in interface HotLoopCallee

eval

protected abstract ExprEval<?> eval()

Implementations override this.