org.bytedeco.arrow

Class RecordBatchFileReader

java.lang.Object

org.bytedeco.javacpp.Pointer

org.bytedeco.arrow.RecordBatchFileReader

All Implemented Interfaces:

AutoCloseable

@Namespace(value="arrow::ipc")
 @NoOffset
 @Properties(inherit=arrow.class)
public class RecordBatchFileReader
extends Pointer

\brief Reads the record batch file format

Nested Class Summary

Nested classes/interfaces inherited from class org.bytedeco.javacpp.Pointer

Pointer.CustomDeallocator, Pointer.Deallocator, Pointer.NativeDeallocator, Pointer.ReferenceCounter

Field Summary

Fields inherited from class org.bytedeco.javacpp.Pointer

address, capacity, limit, position

Constructor Summary

Constructors

Constructor and Description
RecordBatchFileReader(Pointer p) Pointer cast constructor.

Method Summary

Modifier and Type	Method and Description
int	num_record_batches() \brief Returns the number of record batches in the file
static Status	Open(RandomAccessFile file, long footer_offset, RecordBatchFileReader reader) \brief Open a RecordBatchFileReader If the file is embedded within some larger file or memory region, you can pass the absolute memory offset to the end of the file (which contains the metadata footer).
static Status	Open(RandomAccessFile file, RecordBatchFileReader reader) \brief Open a RecordBatchFileReader Open a file-like object that is assumed to be self-contained; i.e., the end of the file interface is the end of the Arrow file.
Status	ReadRecordBatch(int i, RecordBatch batch) \brief Read a particular record batch from the file.
Schema	schema() \brief The schema read from the file
arrow.MetadataVersion	version() \brief Return the metadata version from the file metadata

Methods inherited from class org.bytedeco.javacpp.Pointer

address, asBuffer, asByteBuffer, availablePhysicalBytes, calloc, capacity, capacity, close, deallocate, deallocate, deallocateReferences, deallocator, deallocator, equals, fill, formatBytes, free, hashCode, isNull, isNull, limit, limit, malloc, maxBytes, maxPhysicalBytes, memchr, memcmp, memcpy, memmove, memset, offsetof, parseBytes, physicalBytes, position, position, put, realloc, referenceCount, releaseReference, retainReference, setNull, sizeof, toString, totalBytes, totalPhysicalBytes, withDeallocator, zero

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

RecordBatchFileReader

public RecordBatchFileReader(Pointer p)

Pointer cast constructor. Invokes Pointer.Pointer(Pointer).

Method Detail

Open

@ByVal
public static Status Open(RandomAccessFile file,
                                 @SharedPtr
                                 RecordBatchFileReader reader)

\brief Open a RecordBatchFileReader Open a file-like object that is assumed to be self-contained; i.e., the end of the file interface is the end of the Arrow file. Note that there can be any amount of data preceding the Arrow-formatted data, because we need only locate the end of the Arrow file stream to discover the metadata and then proceed to read the data into memory.

Open

@ByVal
public static Status Open(RandomAccessFile file,
                                 @Cast(value="int64_t")
                                 long footer_offset,
                                 @SharedPtr
                                 RecordBatchFileReader reader)

\brief Open a RecordBatchFileReader If the file is embedded within some larger file or memory region, you can pass the absolute memory offset to the end of the file (which contains the metadata footer). The metadata must have been written with memory offsets relative to the start of the containing file

Parameters:

file - [in] the data source

footer_offset - [in] the position of the end of the Arrow file

reader - [out] the returned reader

Returns:

Status

schema

@SharedPtr
 @ByVal
public Schema schema()

\brief The schema read from the file

num_record_batches

public int num_record_batches()

\brief Returns the number of record batches in the file

version

public arrow.MetadataVersion version()

\brief Return the metadata version from the file metadata

ReadRecordBatch

@ByVal
public Status ReadRecordBatch(int i,
                                     @SharedPtr
                                     RecordBatch batch)

\brief Read a particular record batch from the file. Does not copy memory if the input source supports zero-copy.

Parameters:

i - [in] the index of the record batch to return

batch - [out] the read batch

Returns:

Status