Interface TransferObject<B>
- Type Parameters:
B
-
- All Superinterfaces:
AutoCloseable
,SafeCloseable
- All Known Implementing Classes:
BooleanTransfer
,ByteTransfer
,CharTransfer
,CodecTransfer
,DoubleTransfer
,FloatTransfer
,IntTransfer
,LongTransfer
,ShortTransfer
,StringTransfer
Classes that implement this interface are responsible for converting data from individual DH columns into buffers
to be written out to the Parquet file.
-
Method Summary
Modifier and TypeMethodDescriptionstatic <DATA_TYPE>
TransferObject<?>create
(Map<String, Map<ParquetCacheTags, Object>> computedCache, ReadOnlyIndex tableRowSet, ColumnSource<DATA_TYPE> columnSource, com.illumon.dataobjects.ColumnDefinition<DATA_TYPE> columnDefinition, int maxValuesPerPage, Class<DATA_TYPE> columnType, ParquetInstructions instructions) Create an appropriateTransferObject
to copy data from upstreamColumnSource
s into appropriate buffer format for a ParquetColumnWriter
void
fetchData
(OrderedKeys rs) Copy the data from the upstreamColumnSource
into this object in preparation for writingGet the buffer suitable for writing to a Parquet fileint
rowCount()
Get the number of rows contained within the current transfer set to be written<T extends Comparable<T>>
voidupdateStatistics
(org.apache.parquet.column.statistics.Statistics<T> stats) After a sequence of calls tofetchData(OrderedKeys)
this may be called to append statistic information into the Parquet footer for readers.Methods inherited from interface com.illumon.util.SafeCloseable
close
-
Method Details
-
create
static <DATA_TYPE> TransferObject<?> create(@NotNull Map<String, Map<ParquetCacheTags, Object>> computedCache, @NotNull ReadOnlyIndex tableRowSet, @NotNull ColumnSource<DATA_TYPE> columnSource, @NotNull com.illumon.dataobjects.ColumnDefinition<DATA_TYPE> columnDefinition, int maxValuesPerPage, @NotNull Class<DATA_TYPE> columnType, @NotNull ParquetInstructions instructions) Create an appropriateTransferObject
to copy data from upstreamColumnSource
s into appropriate buffer format for a ParquetColumnWriter
- Type Parameters:
DATA_TYPE
-- Parameters:
computedCache
-tableRowSet
-columnSource
-columnDefinition
-maxValuesPerPage
-columnType
-instructions
-- Returns:
-
getBuffer
B getBuffer()Get the buffer suitable for writing to a Parquet file- Returns:
- the buffer
-
rowCount
int rowCount()Get the number of rows contained within the current transfer set to be written- Returns:
- the number of rows that are ready to write to the Parquet file
-
fetchData
Copy the data from the upstreamColumnSource
into this object in preparation for writing- Parameters:
rs
- theOrderedKeys
to copy
-
updateStatistics
<T extends Comparable<T>> void updateStatistics(@NotNull org.apache.parquet.column.statistics.Statistics<T> stats) After a sequence of calls tofetchData(OrderedKeys)
this may be called to append statistic information into the Parquet footer for readers.- Type Parameters:
T
-- Parameters:
stats
-
-