Package org.apache.druid.frame.field

Class NumericFieldReader

java.lang.Object

org.apache.druid.frame.field.NumericFieldReader

All Implemented Interfaces:

FieldReader

Direct Known Subclasses:

DoubleFieldReader, FloatFieldReader, LongFieldReader

public abstract class NumericFieldReader
extends Object
implements FieldReader

Reads the fields created by the NumericFieldWriter. See the Javadoc for the writer for format details

See Also:

NumericFieldWriter

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	NumericFieldReader.Selector	Helper class which allows the inheritors to fetch the nullity of the field located at fieldPointer's position in the dataRegion.

Constructor Summary

Constructors

Constructor	Description
NumericFieldReader(boolean forArray)

Method Summary

Modifier and Type	Method	Description
abstract ColumnValueSelector<?>	getColumnValueSelector(org.apache.datasketches.memory.Memory memory, ReadableFieldPointer fieldPointer, byte nullIndicatorByte)	Creates a column value selector for the element written at fieldPointer's position in the memory.
abstract ValueType	getValueType()	ValueType of the inheritor's element
boolean	isComparable()	Whether this field is comparable.
boolean	isNull(org.apache.datasketches.memory.Memory memory, long position)	Whether the provided memory position points to a null value.
ColumnValueSelector<?>	makeColumnValueSelector(org.apache.datasketches.memory.Memory memory, ReadableFieldPointer fieldPointer)	Create a ColumnValueSelector backed by some memory and a moveable pointer.
DimensionSelector	makeDimensionSelector(org.apache.datasketches.memory.Memory memory, ReadableFieldPointer fieldPointer, ExtractionFn extractionFn)	Create a DimensionSelector backed by some memory and a moveable pointer.

Methods inherited from class java.lang.Object

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

Constructor Detail

NumericFieldReader

public NumericFieldReader(boolean forArray)

Method Detail

makeColumnValueSelector

public ColumnValueSelector<?> makeColumnValueSelector(org.apache.datasketches.memory.Memory memory,
                                                      ReadableFieldPointer fieldPointer)

Description copied from interface: FieldReader

Create a ColumnValueSelector backed by some memory and a moveable pointer.

Specified by:

makeColumnValueSelector in interface FieldReader

makeDimensionSelector

public DimensionSelector makeDimensionSelector(org.apache.datasketches.memory.Memory memory,
                                               ReadableFieldPointer fieldPointer,
                                               @Nullable
                                               ExtractionFn extractionFn)

Description copied from interface: FieldReader

Create a DimensionSelector backed by some memory and a moveable pointer.

Specified by:

makeDimensionSelector in interface FieldReader

isNull

public boolean isNull(org.apache.datasketches.memory.Memory memory,
                      long position)

Description copied from interface: FieldReader

Whether the provided memory position points to a null value.

Specified by:

isNull in interface FieldReader

isComparable

public boolean isComparable()

Description copied from interface: FieldReader

Whether this field is comparable. Comparable fields can be compared as unsigned bytes.

Specified by:

isComparable in interface FieldReader

getColumnValueSelector

public abstract ColumnValueSelector<?> getColumnValueSelector(org.apache.datasketches.memory.Memory memory,
                                                              ReadableFieldPointer fieldPointer,
                                                              byte nullIndicatorByte)

Creates a column value selector for the element written at fieldPointer's position in the memory. The nullilty check is handled by the nullIndicatorByte

getValueType

public abstract ValueType getValueType()

ValueType of the inheritor's element