org.bytedeco.arrow

Class MemoryMappedFile

java.lang.Object

org.bytedeco.javacpp.Pointer

org.bytedeco.arrow.FileInterface

org.bytedeco.arrow.InputStream

org.bytedeco.arrow.RandomAccessFile

org.bytedeco.arrow.ReadWriteFileInterface

org.bytedeco.arrow.MemoryMappedFile

All Implemented Interfaces:

AutoCloseable

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

\brief A file interface that uses memory-mapped files for memory interactions This implementation supports zero-copy reads. The same class is used for both reading and writing. If opening a file in a writable mode, it is not truncated first as with FileOutputStream.

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
MemoryMappedFile(Pointer p) Pointer cast constructor.

Method Summary

Modifier and Type	Method and Description
Status	Close() \brief Close the stream cleanly For writable streams, this will attempt to flush any pending data before releasing the underlying resource.
boolean	closed() \brief Return whether the stream is closed
static MemoryMappedFileResult	Create(BytePointer path, long size)
static Status	Create(BytePointer path, long size, MemoryMappedFile out) Deprecated.
static MemoryMappedFileResult	Create(String path, long size) Create new file with indicated size, return in read/write mode
static Status	Create(String path, long size, MemoryMappedFile out) Deprecated.
int	file_descriptor()
LongResult	GetSize() Return the total file size in bytes.
static MemoryMappedFileResult	Open(BytePointer path, int mode)
static MemoryMappedFileResult	Open(BytePointer path, int mode, long offset, long length)
static Status	Open(BytePointer path, int mode, long offset, long length, MemoryMappedFile out) Deprecated.
static Status	Open(BytePointer path, int mode, MemoryMappedFile out) Deprecated.
static MemoryMappedFileResult	Open(String path, FileMode.type mode)
static MemoryMappedFileResult	Open(String path, FileMode.type mode, long offset, long length)
static Status	Open(String path, FileMode.type mode, long offset, long length, MemoryMappedFile out) Deprecated.
static Status	Open(String path, FileMode.type mode, MemoryMappedFile out) Deprecated.
BufferResult	Read(long nbytes)
LongResult	Read(long nbytes, Pointer out)
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	Resize(long new_size) \endcond
Status	Seek(long _position)
boolean	supports_zero_copy() \brief Return true if InputStream is capable of zero copy Buffer reads Zero copy reads imply the use of Buffer-returning Read() overloads.
LongResult	Tell() \brief Return the position in this stream
Status	Write(Pointer data, long nbytes) Write data at the current position in the file.
Status	WriteAt(long _position, Pointer data, long nbytes) Write data at a particular position in the file.

Methods inherited from class org.bytedeco.arrow.ReadWriteFileInterface

asWritableFile, asWritableFile

Methods inherited from class org.bytedeco.arrow.RandomAccessFile

asSeekable, asSeekable, GetSize, GetSize, GetSize, GetStream, ReadAt, ReadAt, ReadAt, ReadAt

Methods inherited from class org.bytedeco.arrow.InputStream

Advance, asReadable, asReadable, Peek

Methods inherited from class org.bytedeco.arrow.FileInterface

Abort, mode, Tell, Tell, Tell

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

MemoryMappedFile

public MemoryMappedFile(Pointer p)

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

Method Detail

Create

@ByVal
public static MemoryMappedFileResult Create(@StdString
                                                   String path,
                                                   @Cast(value="int64_t")
                                                   long size)

Create new file with indicated size, return in read/write mode

Create

@ByVal
public static MemoryMappedFileResult Create(@StdString
                                                   BytePointer path,
                                                   @Cast(value="int64_t")
                                                   long size)

Create

@Deprecated
 @ByVal
public static Status Create(@StdString
                                                String path,
                                                @Cast(value="int64_t")
                                                long size,
                                                @SharedPtr
                                                MemoryMappedFile out)

Deprecated.

Create

@Deprecated
 @ByVal
public static Status Create(@StdString
                                                BytePointer path,
                                                @Cast(value="int64_t")
                                                long size,
                                                @SharedPtr
                                                MemoryMappedFile out)

Deprecated.

Open

@ByVal
public static MemoryMappedFileResult Open(@StdString
                                                 String path,
                                                 FileMode.type mode)

Open

@ByVal
public static MemoryMappedFileResult Open(@StdString
                                                 BytePointer path,
                                                 @Cast(value="arrow::io::FileMode::type")
                                                 int mode)

Open

@Deprecated
 @ByVal
public static Status Open(@StdString
                                              String path,
                                              FileMode.type mode,
                                              @SharedPtr
                                              MemoryMappedFile out)

Deprecated.

Open

@Deprecated
 @ByVal
public static Status Open(@StdString
                                              BytePointer path,
                                              @Cast(value="arrow::io::FileMode::type")
                                              int mode,
                                              @SharedPtr
                                              MemoryMappedFile out)

Deprecated.

Open

@ByVal
public static MemoryMappedFileResult Open(@StdString
                                                 String path,
                                                 FileMode.type mode,
                                                 @Cast(value="const int64_t")
                                                 long offset,
                                                 @Cast(value="const int64_t")
                                                 long length)

Open

@ByVal
public static MemoryMappedFileResult Open(@StdString
                                                 BytePointer path,
                                                 @Cast(value="arrow::io::FileMode::type")
                                                 int mode,
                                                 @Cast(value="const int64_t")
                                                 long offset,
                                                 @Cast(value="const int64_t")
                                                 long length)

Open

@Deprecated
 @ByVal
public static Status Open(@StdString
                                              String path,
                                              FileMode.type mode,
                                              @Cast(value="const int64_t")
                                              long offset,
                                              @Cast(value="const int64_t")
                                              long length,
                                              @SharedPtr
                                              MemoryMappedFile out)

Deprecated.

Open

@Deprecated
 @ByVal
public static Status Open(@StdString
                                              BytePointer path,
                                              @Cast(value="arrow::io::FileMode::type")
                                              int mode,
                                              @Cast(value="const int64_t")
                                              long offset,
                                              @Cast(value="const int64_t")
                                              long length,
                                              @SharedPtr
                                              MemoryMappedFile out)

Deprecated.

Close

@ByVal
public Status Close()

Description copied from class: FileInterface

\brief Close the stream cleanly For writable streams, this will attempt to flush any pending data before releasing the underlying resource. After Close() is called, closed() returns true and the stream is not available for further operations.

Overrides:

Close in class FileInterface

closed

@Cast(value="bool")
public boolean closed()

Description copied from class: FileInterface

\brief Return whether the stream is closed

Overrides:

closed in class FileInterface

Tell

@ByVal
public LongResult Tell()

Description copied from class: FileInterface

\brief Return the position in this stream

Overrides:

Tell in class FileInterface

Seek

@ByVal
public Status Seek(@Cast(value="int64_t")
                          long _position)

Read

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

Read

@ByVal
public BufferResult Read(@Cast(value="int64_t")
                                long nbytes)

ReadAt

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

Description copied from class: RandomAccessFile

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

Overrides:

ReadAt in class RandomAccessFile

nbytes - [in] The number of bytes to read

Returns:

A buffer containing the bytes read, or an error

ReadAt

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

Description copied from class: RandomAccessFile

\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.

Overrides:

ReadAt in class RandomAccessFile

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

supports_zero_copy

@Cast(value="bool")
public boolean supports_zero_copy()

Description copied from class: InputStream

\brief Return true if InputStream is capable of zero copy Buffer reads Zero copy reads imply the use of Buffer-returning Read() overloads.

Overrides:

supports_zero_copy in class InputStream

Write

@ByVal
public Status Write(@Const
                           Pointer data,
                           @Cast(value="int64_t")
                           long nbytes)

Write data at the current position in the file. Thread-safe

Resize

@ByVal
public Status Resize(@Cast(value="int64_t")
                            long new_size)

\endcond

Set the size of the map to new_size.

WriteAt

@ByVal
public Status WriteAt(@Cast(value="int64_t")
                             long _position,
                             @Const
                             Pointer data,
                             @Cast(value="int64_t")
                             long nbytes)

Write data at a particular position in the file. Thread-safe

GetSize

@ByVal
public LongResult GetSize()

Description copied from class: RandomAccessFile

Return the total file size in bytes.

Overrides:

GetSize in class RandomAccessFile

file_descriptor

public int file_descriptor()