org.apache.arrow.vector.stream

Class ArrowStreamReader

java.lang.Object

org.apache.arrow.vector.file.ArrowReader<ReadChannel>

org.apache.arrow.vector.stream.ArrowStreamReader

All Implemented Interfaces:

AutoCloseable, DictionaryProvider

public class ArrowStreamReader
extends ArrowReader<ReadChannel>

This classes reads from an input stream and produces ArrowRecordBatches.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.arrow.vector.dictionary.DictionaryProvider

DictionaryProvider.MapDictionaryProvider

Constructor Summary

Constructors

Constructor and Description
ArrowStreamReader(InputStream in, BufferAllocator allocator)
ArrowStreamReader(ReadableByteChannel in, BufferAllocator allocator) Constructs a streaming read, reading bytes from 'in'.

Method Summary

Modifier and Type	Method and Description
protected ArrowMessage	readMessage(ReadChannel in, BufferAllocator allocator)
protected Schema	readSchema(ReadChannel in) Reads the schema message from the beginning of the stream.

Methods inherited from class org.apache.arrow.vector.file.ArrowReader

bytesRead, close, ensureInitialized, getDictionaryVectors, getVectorSchemaRoot, loadNextBatch, lookup

Methods inherited from class java.lang.Object

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

Constructor Detail

ArrowStreamReader

public ArrowStreamReader(ReadableByteChannel in,
                         BufferAllocator allocator)

Constructs a streaming read, reading bytes from 'in'. Non-blocking.

Parameters:

in - the stream to read from

allocator - to allocate new buffers

ArrowStreamReader

public ArrowStreamReader(InputStream in,
                         BufferAllocator allocator)

Method Detail

readSchema

protected Schema readSchema(ReadChannel in)
                     throws IOException

Reads the schema message from the beginning of the stream.

Specified by:

readSchema in class ArrowReader<ReadChannel>

Parameters:

in - to allocate new buffers

Returns:

the deserialized arrow schema

Throws:

IOException

readMessage

protected ArrowMessage readMessage(ReadChannel in,
                                   BufferAllocator allocator)
                            throws IOException

Specified by:

readMessage in class ArrowReader<ReadChannel>

Throws:

IOException