Package io.deephaven.extensions.barrage.chunk

Class RunEndEncodedChunkReader

java.lang.Object

io.deephaven.extensions.barrage.chunk.BaseChunkReader<WritableChunk<Values>>

io.deephaven.extensions.barrage.chunk.RunEndEncodedChunkReader

All Implemented Interfaces:

ChunkReader<WritableChunk<Values>>

public class RunEndEncodedChunkReader
extends BaseChunkReader<WritableChunk<Values>>

Reads an Arrow Run-End Encoded (REE) column from the wire into a flat Deephaven chunk.

The REE parent array has logical length numRows, null_count 0, and zero buffers. The reader consumes one parent ChunkWriter.FieldNodeInfo (no parent buffers), then reads the two children:

1. run_ends — non-nullable Int16/Int32/Int64, numRuns cumulative 1-based end indices (last == numRows)
2. values — the encoded value type, one value per run

The expanded flat output chunk has length numRows and the same element type as the values child.

Nested Class Summary

Nested classes/interfaces inherited from class io.deephaven.extensions.barrage.chunk.BaseChunkReader

BaseChunkReader.ChunkTransformer<READ_CHUNK_TYPE extends Chunk<Values>,DEST_CHUNK_TYPE extends WritableChunk<Values>>

Nested classes/interfaces inherited from interface io.deephaven.extensions.barrage.chunk.ChunkReader

ChunkReader.Factory

Field Summary

Fields inherited from class io.deephaven.extensions.barrage.chunk.BaseChunkReader

BULK_READ_BUFFER_BYTES

Constructor Summary

Constructors

Constructor	Description
RunEndEncodedChunkReader(@NotNull ChunkReader<? extends WritableChunk<Values>> runEndsReader, @NotNull ChunkReader<? extends WritableChunk<Values>> valuesReader, @NotNull ChunkType valuesChunkType)

Method Summary

Modifier and Type	Method	Description
WritableChunk<Values>	readChunk(@NotNull Iterator<ChunkWriter.FieldNodeInfo> fieldNodeIter, PrimitiveIterator.OfLong bufferInfoIter, @NotNull DataInput is, @Nullable WritableChunk<Values> outChunk, int outOffset, int totalRows)	Reads the given DataInput to extract the next Arrow buffer as a Deephaven Chunk.

Methods inherited from class io.deephaven.extensions.barrage.chunk.BaseChunkReader

castOrCreateChunk, getChunkTypeFor, readValidityBuffer

Methods inherited from class java.lang.Object

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

Methods inherited from interface io.deephaven.extensions.barrage.chunk.ChunkReader

readChunk

Constructor Details

RunEndEncodedChunkReader

public RunEndEncodedChunkReader(@NotNull
 @NotNull ChunkReader<? extends WritableChunk<Values>> runEndsReader,
 @NotNull
 @NotNull ChunkReader<? extends WritableChunk<Values>> valuesReader,
 @NotNull
 @NotNull ChunkType valuesChunkType)

Method Details

readChunk

public WritableChunk<Values> readChunk(@NotNull
 @NotNull Iterator<ChunkWriter.FieldNodeInfo> fieldNodeIter,
 @NotNull
 PrimitiveIterator.OfLong bufferInfoIter,
 @NotNull
 @NotNull DataInput is,
 @Nullable
 @Nullable WritableChunk<Values> outChunk,
 int outOffset,
 int totalRows)
                                throws IOException

Description copied from interface: ChunkReader

Reads the given DataInput to extract the next Arrow buffer as a Deephaven Chunk.

Parameters:

fieldNodeIter - iterator to read fields from the stream

bufferInfoIter - iterator to read buffers from the stream

is - input stream containing buffers to be read

outChunk - chunk to write to

outOffset - offset within the outChunk to begin writing

totalRows - total rows to write to the outChunk

Returns:

a Chunk containing the data from the stream

Throws:

IOException - if an error occurred while reading the stream