Package com.illumon.iris.db.v2.locations.parquet

Class ParquetInstructions

java.lang.Object

com.illumon.iris.db.v2.locations.parquet.ParquetInstructions

All Implemented Interfaces:

ColumnToCodecMappings

public abstract class ParquetInstructions
extends Object
implements ColumnToCodecMappings

This class provides instructions intended for read and write parquet operations (which take it as an optional argument) specifying desired transformations. Examples are mapping column names and use of specific codecs during (de)serialization.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	ParquetInstructions.Builder

Field Summary

Fields

Modifier and Type	Field	Description
static ParquetInstructions	EMPTY

Constructor Summary

Constructors

Constructor	Description
ParquetInstructions()

Method Summary

Modifier and Type	Method	Description
static ParquetInstructions.Builder	builder()
abstract String	getCodecArgs(String columnName)
abstract String	getCodecName(String columnName)
abstract String	getColumnNameFromParquetColumnName(String parquetColumnName)
String	getColumnNameFromParquetColumnNameOrDefault(String parquetColumnName)
abstract String	getCompressionCodecName()
static String	getDefaultCompressionCodecName()
static int	getDefaultMaximumDictionaryKeys()
static int	getDefaultTargetPageSize()	Get the current default target page size in bytes.
abstract int	getMaximumDictionaryKeys()
abstract String	getParquetColumnNameFromColumnNameOrDefault(String columnName)
abstract int	getTargetPageSize()
abstract boolean	isLegacyParquet()
static boolean	sameColumnNamesAndCodecMappings(ParquetInstructions i1, ParquetInstructions i2)
static void	setDefaultCompressionCodecName(String name)	Set the default for getCompressionCodecName().
static void	setDefaultMaximumDictionaryKeys(int maximumDictionaryKeys)	Set the default for getMaximumDictionaryKeys().
static void	setDefaultTargetPageSize(int newDefaultSizeBytes)	Set the default target page size (in bytes) used to section rows of data into pages during column writing.
abstract boolean	useDictionary(String columnName)

Methods inherited from class java.lang.Object

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

Field Details

EMPTY

public static final ParquetInstructions EMPTY

Constructor Details

ParquetInstructions

public ParquetInstructions()

Method Details

setDefaultCompressionCodecName

public static void setDefaultCompressionCodecName(String name)

Set the default for getCompressionCodecName().

Parameters:

name - The new default

See Also:

ParquetInstructions.Builder.setCompressionCodecName(String)

getDefaultCompressionCodecName

public static String getDefaultCompressionCodecName()

Returns:

The default for getCompressionCodecName()

setDefaultMaximumDictionaryKeys

public static void setDefaultMaximumDictionaryKeys(int maximumDictionaryKeys)

Set the default for getMaximumDictionaryKeys().

Parameters:

maximumDictionaryKeys - The new default

See Also:

ParquetInstructions.Builder.setMaximumDictionaryKeys(int)

getDefaultMaximumDictionaryKeys

public static int getDefaultMaximumDictionaryKeys()

Returns:

The default for getMaximumDictionaryKeys()

setDefaultTargetPageSize

public static void setDefaultTargetPageSize(int newDefaultSizeBytes)

Set the default target page size (in bytes) used to section rows of data into pages during column writing. This number should be no smaller than 65536.

Parameters:

newDefaultSizeBytes - the new default target page size.

getDefaultTargetPageSize

public static int getDefaultTargetPageSize()

Get the current default target page size in bytes.

Returns:

the current default target page size in bytes.

getColumnNameFromParquetColumnNameOrDefault

public final String getColumnNameFromParquetColumnNameOrDefault(String parquetColumnName)

getParquetColumnNameFromColumnNameOrDefault

public abstract String getParquetColumnNameFromColumnNameOrDefault(String columnName)

getColumnNameFromParquetColumnName

public abstract String getColumnNameFromParquetColumnName(String parquetColumnName)

getCodecName

public abstract String getCodecName(String columnName)

Specified by:

getCodecName in interface ColumnToCodecMappings

getCodecArgs

public abstract String getCodecArgs(String columnName)

Specified by:

getCodecArgs in interface ColumnToCodecMappings

useDictionary

public abstract boolean useDictionary(String columnName)

Returns:

A hint that the writer should use dictionary-based encoding for writing this column; never evaluated for non-String columns, defaults to false

getCompressionCodecName

public abstract String getCompressionCodecName()

getMaximumDictionaryKeys

public abstract int getMaximumDictionaryKeys()

Returns:

The maximum number of unique keys the writer should add to a dictionary page before switching to non-dictionary encoding; never evaluated for non-String columns, ignored if useDictionary(String)

isLegacyParquet

public abstract boolean isLegacyParquet()

getTargetPageSize

public abstract int getTargetPageSize()

sameColumnNamesAndCodecMappings

@VisibleForTesting public static boolean sameColumnNamesAndCodecMappings(ParquetInstructions i1, ParquetInstructions i2)

builder

public static ParquetInstructions.Builder builder()