uk.ac.starlink.table

Class RowRunner

java.lang.Object

uk.ac.starlink.table.RowRunner

public class RowRunner
extends Object

Manages potentially parallel processing of StarTable row data.

Since:

5 Aug 2020

Author:

Mark Taylor

Field Summary

Fields

Modifier and Type	Field and Description
static RowRunner	DEFAULT General purpose instance; will be parallel for suitable environments.
static SplitPolicy	DFLT_POLICY Default split policy.
static RowRunner	PARTEST Testing instance; force parallel processing even for small tables.
static RowRunner	SEQUENTIAL Sequential-only instance; no parallel processing.

Constructor Summary

Constructors

Constructor and Description
RowRunner(SplitProcessor<?> processor) Constructor.

Method Summary

Modifier and Type	Method and Description
<A> A	collect(RowCollector<A> collector, StarTable table) Performs a collection operation on table rows.
RowSplittable	createRowSplittable(StarTable table) Acquires a splittable row sequence from a table.
SplitProcessor<RowSplittable>	getSplitProcessor() Returns the processor on which this runner is based.

Methods inherited from class java.lang.Object

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

Field Detail

DFLT_POLICY

public static final SplitPolicy DFLT_POLICY

Default split policy.

DEFAULT

public static final RowRunner DEFAULT

General purpose instance; will be parallel for suitable environments.

SEQUENTIAL

public static final RowRunner SEQUENTIAL

Sequential-only instance; no parallel processing.

PARTEST

public static final RowRunner PARTEST

Testing instance; force parallel processing even for small tables.

Constructor Detail

RowRunner

public RowRunner(SplitProcessor<?> processor)

Constructor.

Parameters:

processor - processor that manages the executions

Method Detail

collect

public <A> A collect(RowCollector<A> collector,
                     StarTable table)
              throws IOException

Performs a collection operation on table rows.

Parameters:

collector - collector defining operation

table - table supplying data

Returns:

result of collection

Throws:

IOException

createRowSplittable

public RowSplittable createRowSplittable(StarTable table)
                                  throws IOException

Acquires a splittable row sequence from a table. The default implementation just calls StarTable.getRowSplittable(), but this may be overridden if required.

Parameters:

table - input table

Returns:

potentially splittable row sequence

Throws:

IOException

getSplitProcessor

public SplitProcessor<RowSplittable> getSplitProcessor()

Returns the processor on which this runner is based.

Returns:

processor