parquet.column.values

Interface RequiresFallback

All Known Implementing Classes:

DictionaryValuesWriter, DictionaryValuesWriter.PlainBinaryDictionaryValuesWriter, DictionaryValuesWriter.PlainDoubleDictionaryValuesWriter, DictionaryValuesWriter.PlainFixedLenArrayDictionaryValuesWriter, DictionaryValuesWriter.PlainFloatDictionaryValuesWriter, DictionaryValuesWriter.PlainIntegerDictionaryValuesWriter, DictionaryValuesWriter.PlainLongDictionaryValuesWriter

public interface RequiresFallback

Used to add extra behavior to a ValuesWriter that requires fallback

Author:

Julien Le Dem

Method Summary

Methods

Modifier and Type	Method and Description
void	fallBackAllValuesTo(ValuesWriter writer) When falling back to a different encoding we must re-encode all the values seen so far
boolean	isCompressionSatisfying(long rawSize, long encodedSize) Before writing the first page we will verify if the encoding is worth it.
boolean	shouldFallBack() In the case of a dictionary based encoding we will fallback if the dictionary becomes too big

Method Detail

shouldFallBack

boolean shouldFallBack()

In the case of a dictionary based encoding we will fallback if the dictionary becomes too big

Returns:

true to notify the parent that we should fallback to another encoding

isCompressionSatisfying

boolean isCompressionSatisfying(long rawSize,
                              long encodedSize)

Before writing the first page we will verify if the encoding is worth it. and fall back if a simpler encoding would be better in that case

Parameters:

rawSize - the size if encoded with plain

encodedSize - the size as encoded by the current encoding

Returns:

true if we keep this encoding

fallBackAllValuesTo

void fallBackAllValuesTo(ValuesWriter writer)

When falling back to a different encoding we must re-encode all the values seen so far

Parameters:

writer - the new encoder to write the current values to