Package org.apache.drill.exec.vector.accessor.reader

Class OffsetVectorReader

java.lang.Object

org.apache.drill.exec.vector.accessor.reader.AbstractScalarReader

org.apache.drill.exec.vector.accessor.reader.BaseScalarReader

org.apache.drill.exec.vector.accessor.reader.BaseScalarReader.BaseFixedWidthReader

org.apache.drill.exec.vector.accessor.reader.OffsetVectorReader

All Implemented Interfaces:

ColumnReader, ReaderEvents, ScalarReader

public class OffsetVectorReader
extends BaseScalarReader.BaseFixedWidthReader

Reader for an offset vector.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.drill.exec.vector.accessor.reader.BaseScalarReader

BaseScalarReader.BaseFixedWidthReader, BaseScalarReader.BaseVarWidthReader, BaseScalarReader.BufferAccessor

Nested classes/interfaces inherited from class org.apache.drill.exec.vector.accessor.reader.AbstractScalarReader

AbstractScalarReader.NullReader, AbstractScalarReader.ScalarObjectReader

Field Summary

Fields inherited from class org.apache.drill.exec.vector.accessor.reader.BaseScalarReader

bufferAccessor, schema, vectorAccessor

Fields inherited from class org.apache.drill.exec.vector.accessor.reader.AbstractScalarReader

nullStateReader, vectorIndex

Constructor Summary

Constructors

Constructor	Description
OffsetVectorReader(VectorAccessor offsetsAccessor)

Method Summary

Modifier and Type	Method	Description
long	getEntry()	Return the offset and length of a value encoded as a long.
void	reposition()
ColumnMetadata	schema()
ValueType	valueType()	Describe the type of the value.
int	width()

Methods inherited from class org.apache.drill.exec.vector.accessor.reader.BaseScalarReader.BaseFixedWidthReader

offsetIndex

Methods inherited from class org.apache.drill.exec.vector.accessor.reader.BaseScalarReader

bindBuffer, bindIndex, bindVector, buffer, bufferAccessor, buildOptional, buildRequired

Methods inherited from class org.apache.drill.exec.vector.accessor.reader.AbstractScalarReader

bindNullState, conversionError, extendedType, getAsString, getBoolean, getBytes, getDate, getDecimal, getDouble, getFloat, getInt, getLong, getObject, getPeriod, getString, getTime, getTimestamp, getValue, isNull, nullReader, nullStateReader, type

Methods inherited from class java.lang.Object

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

Constructor Details

OffsetVectorReader

public OffsetVectorReader(VectorAccessor offsetsAccessor)

Method Details

valueType

public ValueType valueType()

Description copied from interface: ScalarReader

Describe the type of the value. This is a compression of the value vector type: it describes which method will return the vector value.

Returns:

the value type which indicates which get method is valid for the column

width

public int width()

Specified by:

width in class BaseScalarReader.BaseFixedWidthReader

getEntry

public long getEntry()

Return the offset and length of a value encoded as a long. The value is encoded to avoid the need to resolve the offset vector twice per value.

Returns:

a long with the format:
Upper 32 bits - offset: offset = (int) (entry >> 32)
Lower 32 bits - length: length = (int) (entry & 0xFFFF_FFFF)

reposition

public void reposition()

Specified by:

reposition in interface ReaderEvents

Overrides:

reposition in class AbstractScalarReader

schema

public ColumnMetadata schema()

Specified by:

schema in interface ColumnReader

Overrides:

schema in class BaseScalarReader