Package io.deephaven.extensions.barrage.chunk

Interface ChunkWriter<SOURCE_CHUNK_TYPE extends Chunk<Values>>

Type Parameters:

SOURCE_CHUNK_TYPE - The type of chunk of source data, extending Chunk with Values.

All Known Implementing Classes:

BaseChunkWriter, BigDecimalChunkWriter, BooleanChunkWriter, ByteChunkWriter, CharChunkWriter, DoubleChunkWriter, FixedWidthChunkWriter, FixedWidthObjectChunkWriter, FloatChunkWriter, IntChunkWriter, ListChunkWriter, LongChunkWriter, MapChunkWriter, NullChunkWriter, ShortChunkWriter, UnionChunkWriter, VarBinaryChunkWriter

public interface ChunkWriter<SOURCE_CHUNK_TYPE extends Chunk<Values>>

The ChunkWriter interface provides a mechanism for writing chunks of data into a structured format suitable for transmission in Apache Arrow's columnar format. It enables efficient handling of chunked data, including support for various data types and logical structures. This interface is part of the Deephaven Barrage extensions for efficient data streaming and processing.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	ChunkWriter.BufferListener
static class	ChunkWriter.Context
static class	ChunkWriter.DrainableColumn
static interface	ChunkWriter.Factory	Creator of ChunkWriter instances.
static final class	ChunkWriter.FieldNodeInfo
static interface	ChunkWriter.FieldNodeListener

Method Summary

Modifier and Type	Method	Description
ChunkWriter.DrainableColumn	getEmptyInputStream(@NotNull BarrageOptions options)	Get an input stream representing the empty wire payload for this writer.
ChunkWriter.DrainableColumn	getInputStream(@NotNull ChunkWriter.Context context, @Nullable RowSet subset, @NotNull BarrageOptions options)	Get an input stream optionally position-space filtered using the provided RowSet.
boolean	isFieldNullable()
ChunkWriter.Context	makeContext(SOURCE_CHUNK_TYPE chunk, long rowOffset)	Create a context for the given chunk.

Method Details

makeContext

ChunkWriter.Context makeContext(@NotNull
 SOURCE_CHUNK_TYPE chunk,
 long rowOffset)

Create a context for the given chunk.

Parameters:

chunk - the chunk of data to be written

rowOffset - the offset into the logical message potentially spread over multiple chunks

Returns:

a context for the given chunk

getInputStream

ChunkWriter.DrainableColumn getInputStream(@NotNull
 @NotNull ChunkWriter.Context context,
 @Nullable
 @Nullable RowSet subset,
 @NotNull
 @NotNull BarrageOptions options)
                                    throws IOException

Get an input stream optionally position-space filtered using the provided RowSet.

Parameters:

context - the chunk writer context holding the data to be drained to the client

subset - if provided, is a position-space filter of source data

options - options for writing to the stream

Returns:

a single-use DrainableColumn ready to be drained via grpc

Throws:

IOException

getEmptyInputStream

ChunkWriter.DrainableColumn getEmptyInputStream(@NotNull
 @NotNull BarrageOptions options)
                                         throws IOException

Get an input stream representing the empty wire payload for this writer.

Parameters:

options - options for writing to the stream

Returns:

a single-use DrainableColumn ready to be drained via grpc

Throws:

IOException

isFieldNullable

boolean isFieldNullable()

Returns:

whether the wire format for this writer might include a validity buffer