org.bytedeco.arrow

Class RandomAccessFile

java.lang.Object

org.bytedeco.javacpp.Pointer

org.bytedeco.arrow.RandomAccessFile

All Implemented Interfaces:

AutoCloseable

Direct Known Subclasses:

BufferReaderRandomAccessFileConcurrencyWrapper, HdfsReadableFile, ParquetInputWrapper, RandomAccessFileSlowInputStreamBase, ReadableFileRandomAccessFileConcurrencyWrapper, ReadWriteFileInterface

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

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
RandomAccessFile(Pointer p) Pointer cast constructor.

Method Summary

Modifier and Type	Method and Description
InputStream	asInputStream()
static InputStream	asInputStream(RandomAccessFile pointer)
Seekable	asSeekable()
static Seekable	asSeekable(RandomAccessFile pointer)
LongResult	GetSize() \brief Return the total file size in bytes.
static InputStream	GetStream(RandomAccessFile file, long file_offset, long nbytes) \brief Create an isolated InputStream that reads a segment of a RandomAccessFile.
BufferResult	ReadAt(long _position, long nbytes) \brief Read data from given file position.
LongResult	ReadAt(long _position, long nbytes, Pointer out) \brief Read data from given file position.
Status	WillNeed(ReadRange ranges) EXPERIMENTAL: Inform that the given ranges may be read soon.

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, getPointer, getPointer, getPointer, getPointer, hashCode, isNull, isNull, limit, limit, malloc, maxBytes, maxPhysicalBytes, memchr, memcmp, memcpy, memmove, memset, offsetof, offsetof, parseBytes, physicalBytes, position, position, put, realloc, referenceCount, releaseReference, retainReference, setNull, sizeof, sizeof, toString, totalBytes, totalCount, totalPhysicalBytes, withDeallocator, zero

Methods inherited from class java.lang.Object

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

Constructor Detail

RandomAccessFile

public RandomAccessFile(Pointer p)

Pointer cast constructor. Invokes Pointer(Pointer).

Method Detail

asInputStream

public InputStream asInputStream()

asInputStream

@Namespace
 @Name(value="static_cast<arrow::io::InputStream*>")
public static InputStream asInputStream(RandomAccessFile pointer)

asSeekable

public Seekable asSeekable()

asSeekable

@Namespace
 @Name(value="static_cast<arrow::io::Seekable*>")
public static Seekable asSeekable(RandomAccessFile pointer)

GetStream

@SharedPtr
public static InputStream GetStream(@SharedPtr @Cast(value={"","std::shared_ptr<arrow::io::RandomAccessFile>"})
                                                RandomAccessFile file,
                                                @Cast(value="int64_t")
                                                long file_offset,
                                                @Cast(value="int64_t")
                                                long nbytes)

\brief Create an isolated InputStream that reads a segment of a RandomAccessFile. Multiple such stream can be created and used independently without interference

Parameters:

file - [in] a file instance

file_offset - [in] the starting position in the file

nbytes - [in] the extent of bytes to read. The file should have sufficient bytes available

GetSize

@ByVal
public LongResult GetSize()

\brief Return the total file size in bytes. This method does not read or move the current file position, so is safe to call concurrently with e.g. ReadAt().

ReadAt

@ByVal
public LongResult ReadAt(@Cast(value="int64_t")
                                 long _position,
                                 @Cast(value="int64_t")
                                 long nbytes,
                                 Pointer out)

\brief Read data from given file position. At most nbytes bytes are read. The number of bytes read is returned (it can be less than nbytes if EOF is reached). This method can be safely called from multiple threads concurrently. It is unspecified whether this method updates the file position or not. The default RandomAccessFile-provided implementation uses Seek() and Read(), but subclasses may override it with a more efficient implementation that doesn't depend on implicit file positioning.

Parameters:

position - [in] Where to read bytes from

nbytes - [in] The number of bytes to read

out - [out] The buffer to read bytes into

Returns:

The number of bytes read, or an error

ReadAt

@ByVal
public BufferResult ReadAt(@Cast(value="int64_t")
                                   long _position,
                                   @Cast(value="int64_t")
                                   long nbytes)

\brief Read data from given file position. At most nbytes bytes are read, but it can be less if EOF is reached.

Parameters:

position - [in] Where to read bytes from

nbytes - [in] The number of bytes to read

Returns:

A buffer containing the bytes read, or an error

WillNeed

@ByVal
public Status WillNeed(@StdVector
                               ReadRange ranges)

EXPERIMENTAL: Inform that the given ranges may be read soon. Some implementations might arrange to prefetch some of the data. However, no guarantee is made and the default implementation does nothing. For robust prefetching, use ReadAt() or ReadAsync().