org.apache.drill.exec.physical.impl.xsort

Class BatchGroup

java.lang.Object

org.apache.drill.exec.physical.impl.xsort.BatchGroup

All Implemented Interfaces:

AutoCloseable, Iterable<VectorWrapper<?>>, VectorAccessible

Direct Known Subclasses:

InputBatch, SpilledRun

public abstract class BatchGroup
extends Object
implements VectorAccessible, AutoCloseable

Represents a group of batches spilled to disk.

The batches are defined by a schema which can change over time. When the schema changes, all existing and new batches are coerced into the new schema. Provides a uniform way to iterate over records for one or more batches whether the batches are in memory or on disk.

The BatchGroup operates in two modes as given by the two subclasses:

• Input mode InputBatch: Used to buffer in-memory batches prior to spilling.
• Spill mode SpilledRun: Holds a "memento" to a set of batches written to disk. Acts as both a reader and writer for those batches.

Field Summary

Fields

Modifier and Type	Field and Description
protected BufferAllocator	allocator
protected VectorContainer	currentContainer
protected int	mergeIndex This class acts as both "holder" for a vector container and an iterator into that container when the sort enters the merge phase.
protected BatchSchema	schema

Constructor Summary

Constructors

Constructor and Description
BatchGroup(VectorContainer container, BufferAllocator allocator)

Method Summary

Modifier and Type	Method and Description
void	close()
static void	closeAll(Collection<? extends BatchGroup> groups)
VectorContainer	getContainer()
int	getNextIndex()
int	getRecordCount() Get the number of records.
BatchSchema	getSchema() Get the schema of the current RecordBatch.
SelectionVector2	getSelectionVector2()
SelectionVector4	getSelectionVector4()
int	getUnfilteredRecordCount()
VectorWrapper<?>	getValueAccessorById(Class<?> clazz, int... ids)
TypedFieldId	getValueVectorId(SchemaPath path) Get the value vector type and id for the given schema path.
Iterator<VectorWrapper<?>>	iterator()
void	setSchema(BatchSchema schema) Updates the schema for this batch group.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Detail

allocator

protected final BufferAllocator allocator

currentContainer

protected VectorContainer currentContainer

mergeIndex

protected int mergeIndex

This class acts as both "holder" for a vector container and an iterator into that container when the sort enters the merge phase. (This should be revisited.) This field keeps track of the next record to merge during the merge phase.

schema

protected BatchSchema schema

Constructor Detail

BatchGroup

public BatchGroup(VectorContainer container,
                  BufferAllocator allocator)

Method Detail

setSchema

public void setSchema(BatchSchema schema)

Updates the schema for this batch group. The current as well as any deserialized batches will be coerced to this schema.

Parameters:

schema -

getNextIndex

public int getNextIndex()

getContainer

public VectorContainer getContainer()

close

public void close()
           throws IOException

Specified by:

close in interface AutoCloseable

Throws:

IOException

getValueAccessorById

public VectorWrapper<?> getValueAccessorById(Class<?> clazz,
                                             int... ids)

Specified by:

getValueAccessorById in interface VectorAccessible

getValueVectorId

public TypedFieldId getValueVectorId(SchemaPath path)

Description copied from interface: VectorAccessible

Get the value vector type and id for the given schema path. The TypedFieldId should store a fieldId which is the same as the ordinal position of the field within the Iterator provided this classes implementation of Iterable<ValueVector>.

Specified by:

getValueVectorId in interface VectorAccessible

Parameters:

path - the path where the vector should be located.

Returns:

the local field id associated with this vector. If no field matches this path, this will return a null TypedFieldId

getSchema

public BatchSchema getSchema()

Description copied from interface: VectorAccessible

Get the schema of the current RecordBatch. This changes if and only if a *_NEW_SCHEMA IterOutcome is provided.

Specified by:

getSchema in interface VectorAccessible

Returns:

schema of the current batch

getRecordCount

public int getRecordCount()

Description copied from interface: VectorAccessible

Get the number of records.

Specified by:

getRecordCount in interface VectorAccessible

Returns:

number of records

getUnfilteredRecordCount

public int getUnfilteredRecordCount()

iterator

public Iterator<VectorWrapper<?>> iterator()

Specified by:

iterator in interface Iterable<VectorWrapper<?>>

getSelectionVector2

public SelectionVector2 getSelectionVector2()

Specified by:

getSelectionVector2 in interface VectorAccessible

getSelectionVector4

public SelectionVector4 getSelectionVector4()

Specified by:

getSelectionVector4 in interface VectorAccessible

closeAll

public static void closeAll(Collection<? extends BatchGroup> groups)