org.bytedeco.arrow

Class ArrowBuffer

java.lang.Object

org.bytedeco.javacpp.Pointer

org.bytedeco.arrow.ArrowBuffer

All Implemented Interfaces:

AutoCloseable

Direct Known Subclasses:

MutableBuffer

@Name(value="arrow::Buffer")
 @NoOffset
 @Properties(inherit=arrow.class)
public class ArrowBuffer
extends Pointer

\class Buffer \brief Object containing a pointer to a piece of contiguous memory with a particular size. Buffers have two related notions of length: size and capacity. Size is the number of bytes that might have valid data. Capacity is the number of bytes that were allocated for the buffer in total. The Buffer base class does not own its memory, but subclasses often do. The following invariant is always true: Size <= Capacity

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
ArrowBuffer(ArrowBuffer parent, long offset, long size) An offset into data that is owned by another buffer, but we want to be able to retain a valid pointer to it even after other shared_ptr's to the parent buffer have been destroyed This method makes no assertions about alignment or padding of the buffer but in general we expected buffers to be aligned and padded to 64 bytes.
ArrowBuffer(byte[] data, long size)
ArrowBuffer(byte[] data, long size, MemoryManager mm)
ArrowBuffer(byte[] data, long size, MemoryManager mm, ArrowBuffer parent)
ArrowBuffer(ByteBuffer data, long size)
ArrowBuffer(ByteBuffer data, long size, MemoryManager mm)
ArrowBuffer(ByteBuffer data, long size, MemoryManager mm, ArrowBuffer parent)
ArrowBuffer(BytePointer data, long size) \brief Construct from buffer and size without copying memory
ArrowBuffer(BytePointer data, long size, MemoryManager mm)
ArrowBuffer(BytePointer data, long size, MemoryManager mm, ArrowBuffer parent)
ArrowBuffer(long _address, long size, MemoryManager mm)
ArrowBuffer(long _address, long size, MemoryManager mm, ArrowBuffer parent)
ArrowBuffer(Pointer p) Pointer cast constructor.

Method Summary

Modifier and Type	Method and Description
long	_address() \brief Return the device address of the buffer's data
long	_capacity() \brief Return the buffer's capacity (number of allocated bytes)
static BufferResult	Copy(ArrowBuffer source, MemoryManager to) \brief Copy buffer The buffer contents will be copied into a new buffer allocated by the given MemoryManager.
BufferResult	CopySlice(long start, long nbytes)
BufferResult	CopySlice(long start, long nbytes, MemoryPool pool) Copy a section of the buffer into a new Buffer.
BytePointer	data() \brief Return a pointer to the buffer's data The buffer has to be a CPU buffer (is_cpu() is true).
Device	device()
boolean	Equals(ArrowBuffer other) Return true if both buffers are the same size and contain the same bytes
boolean	Equals(ArrowBuffer other, long nbytes) Return true if both buffers are the same size and contain the same bytes up to the number of compared bytes
static ArrowBuffer	FromString(BytePointer data) \brief Construct an immutable buffer that takes ownership of the contents of an std::string (without copying it).
static ArrowBuffer	FromString(String data)
byte	get(long i)
static RandomAccessFileResult	GetReader(ArrowBuffer arg0) \brief Get a RandomAccessFile for reading a buffer The returned file object reads from this buffer's underlying memory.
static OutputStreamResult	GetWriter(ArrowBuffer arg0) \brief Get a OutputStream for writing to a buffer The buffer must be mutable.
boolean	is_cpu() \brief Whether the buffer is directly CPU-accessible If this function returns true, you can read directly from the buffer's data() pointer.
boolean	is_mutable() \brief Whether the buffer is mutable If this function returns true, you are allowed to modify buffer contents using the pointer returned by mutable_data() or mutable_address().
MemoryManager	memory_manager()
long	mutable_address() \brief Return a writable device address to the buffer's data The buffer has to be a mutable buffer (is_mutable() is true).
BytePointer	mutable_data() \brief Return a writable pointer to the buffer's data The buffer has to be a mutable CPU buffer (is_cpu() and is_mutable() are true).
ArrowBuffer	parent()
long	size() \brief Return the buffer's size in bytes
String	ToHexString() \brief Construct a new std::string with a hexadecimal representation of the buffer.
String	ToString() \brief Copy buffer contents into a new std::string
static BufferResult	View(ArrowBuffer source, MemoryManager to) \brief View buffer Return a Buffer that reflects this buffer, seen potentially from another device, without making an explicit copy of the contents.
static BufferResult	ViewOrCopy(ArrowBuffer source, MemoryManager to) \brief View or copy buffer Try to view buffer contents on the given MemoryManager's device, but fall back to copying if a no-copy view isn't supported.
void	ZeroPadding() Zero bytes in padding, i.e.

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

ArrowBuffer

public ArrowBuffer(Pointer p)

Pointer cast constructor. Invokes Pointer(Pointer).

ArrowBuffer

public ArrowBuffer(@Cast(value="const uint8_t*")
                   BytePointer data,
                   @Cast(value="int64_t")
                   long size)

\brief Construct from buffer and size without copying memory

Parameters:

data - [in] a memory buffer

size - [in] buffer size \note The passed memory must be kept alive through some other means

ArrowBuffer

public ArrowBuffer(@Cast(value="const uint8_t*")
                   ByteBuffer data,
                   @Cast(value="int64_t")
                   long size)

ArrowBuffer

public ArrowBuffer(@Cast(value="const uint8_t*")
                   byte[] data,
                   @Cast(value="int64_t")
                   long size)

ArrowBuffer

public ArrowBuffer(@Cast(value="const uint8_t*")
                   BytePointer data,
                   @Cast(value="int64_t")
                   long size,
                   @SharedPtr
                   MemoryManager mm,
                   @SharedPtr
                   ArrowBuffer parent)

ArrowBuffer

public ArrowBuffer(@Cast(value="const uint8_t*")
                   BytePointer data,
                   @Cast(value="int64_t")
                   long size,
                   @SharedPtr
                   MemoryManager mm)

ArrowBuffer

public ArrowBuffer(@Cast(value="const uint8_t*")
                   ByteBuffer data,
                   @Cast(value="int64_t")
                   long size,
                   @SharedPtr
                   MemoryManager mm,
                   @SharedPtr
                   ArrowBuffer parent)

ArrowBuffer

public ArrowBuffer(@Cast(value="const uint8_t*")
                   ByteBuffer data,
                   @Cast(value="int64_t")
                   long size,
                   @SharedPtr
                   MemoryManager mm)

ArrowBuffer

public ArrowBuffer(@Cast(value="const uint8_t*")
                   byte[] data,
                   @Cast(value="int64_t")
                   long size,
                   @SharedPtr
                   MemoryManager mm,
                   @SharedPtr
                   ArrowBuffer parent)

ArrowBuffer

public ArrowBuffer(@Cast(value="const uint8_t*")
                   byte[] data,
                   @Cast(value="int64_t")
                   long size,
                   @SharedPtr
                   MemoryManager mm)

ArrowBuffer

public ArrowBuffer(@Cast(value="uintptr_t")
                   long _address,
                   @Cast(value="int64_t")
                   long size,
                   @SharedPtr
                   MemoryManager mm,
                   @SharedPtr
                   ArrowBuffer parent)

ArrowBuffer

public ArrowBuffer(@Cast(value="uintptr_t")
                   long _address,
                   @Cast(value="int64_t")
                   long size,
                   @SharedPtr
                   MemoryManager mm)

ArrowBuffer

public ArrowBuffer(@SharedPtr
                   ArrowBuffer parent,
                   @Cast(value="const int64_t")
                   long offset,
                   @Cast(value="const int64_t")
                   long size)

An offset into data that is owned by another buffer, but we want to be able to retain a valid pointer to it even after other shared_ptr's to the parent buffer have been destroyed This method makes no assertions about alignment or padding of the buffer but in general we expected buffers to be aligned and padded to 64 bytes. In the future we might add utility methods to help determine if a buffer satisfies this contract.

Method Detail

get

@Cast(value="uint8_t")
 @Name(value="operator []")
public byte get(@Cast(value="std::size_t")
                                                                     long i)

ToHexString

@StdString
public String ToHexString()

\brief Construct a new std::string with a hexadecimal representation of the buffer.

Returns:

std::string

Equals

@Cast(value="bool")
public boolean Equals(@Const @ByRef
                                           ArrowBuffer other,
                                           @Cast(value="int64_t")
                                           long nbytes)

Return true if both buffers are the same size and contain the same bytes up to the number of compared bytes

Equals

@Cast(value="bool")
public boolean Equals(@Const @ByRef
                                           ArrowBuffer other)

Return true if both buffers are the same size and contain the same bytes

CopySlice

@ByVal
public BufferResult CopySlice(@Cast(value="const int64_t")
                                      long start,
                                      @Cast(value="const int64_t")
                                      long nbytes,
                                      MemoryPool pool)

Copy a section of the buffer into a new Buffer.

CopySlice

@ByVal
public BufferResult CopySlice(@Cast(value="const int64_t")
                                      long start,
                                      @Cast(value="const int64_t")
                                      long nbytes)

ZeroPadding

public void ZeroPadding()

Zero bytes in padding, i.e. bytes between size_ and capacity_.

FromString

@SharedPtr
 @ByVal
public static ArrowBuffer FromString(@Cast(value={"","std::string&&"}) @StdString
                                                          BytePointer data)

\brief Construct an immutable buffer that takes ownership of the contents of an std::string (without copying it).

Parameters:

data - [in] a string to own

Returns:

a new Buffer instance

FromString

@SharedPtr
 @ByVal
public static ArrowBuffer FromString(@Cast(value={"","std::string&&"}) @StdString
                                                          String data)

ToString

@StdString
public String ToString()

\brief Copy buffer contents into a new std::string

Returns:

std::string \note Can throw std::bad_alloc if buffer is large

data

@Cast(value="const uint8_t*")
public BytePointer data()

\brief Return a pointer to the buffer's data The buffer has to be a CPU buffer (is_cpu() is true). Otherwise, an assertion may be thrown or a null pointer may be returned. To get the buffer's data address regardless of its device, call address().

mutable_data

@Cast(value="uint8_t*")
public BytePointer mutable_data()

\brief Return a writable pointer to the buffer's data The buffer has to be a mutable CPU buffer (is_cpu() and is_mutable() are true). Otherwise, an assertion may be thrown or a null pointer may be returned. To get the buffer's mutable data address regardless of its device, call mutable_address().

_address

@Cast(value="uintptr_t")
 @Name(value="address")
public long _address()

\brief Return the device address of the buffer's data

mutable_address

@Cast(value="uintptr_t")
public long mutable_address()

\brief Return a writable device address to the buffer's data The buffer has to be a mutable buffer (is_mutable() is true). Otherwise, an assertion may be thrown or 0 may be returned.

size

@Cast(value="int64_t")
public long size()

\brief Return the buffer's size in bytes

_capacity

@Cast(value="int64_t")
 @Name(value="capacity")
public long _capacity()

\brief Return the buffer's capacity (number of allocated bytes)

is_cpu

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

\brief Whether the buffer is directly CPU-accessible If this function returns true, you can read directly from the buffer's data() pointer. Otherwise, you'll have to View() or Copy() it.

is_mutable

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

\brief Whether the buffer is mutable If this function returns true, you are allowed to modify buffer contents using the pointer returned by mutable_data() or mutable_address().

device

@SharedPtr
public Device device()

memory_manager

@SharedPtr
public MemoryManager memory_manager()

parent

@SharedPtr
public ArrowBuffer parent()

GetReader

@ByVal
public static RandomAccessFileResult GetReader(@SharedPtr
                                                       ArrowBuffer arg0)

\brief Get a RandomAccessFile for reading a buffer The returned file object reads from this buffer's underlying memory.

GetWriter

@ByVal
public static OutputStreamResult GetWriter(@SharedPtr
                                                   ArrowBuffer arg0)

\brief Get a OutputStream for writing to a buffer The buffer must be mutable. The returned stream object writes into the buffer's underlying memory (but it won't resize it).

Copy

@ByVal
public static BufferResult Copy(@SharedPtr
                                        ArrowBuffer source,
                                        @SharedPtr
                                        MemoryManager to)

\brief Copy buffer The buffer contents will be copied into a new buffer allocated by the given MemoryManager. This function supports cross-device copies.

View

@ByVal
public static BufferResult View(@SharedPtr
                                        ArrowBuffer source,
                                        @SharedPtr
                                        MemoryManager to)

\brief View buffer Return a Buffer that reflects this buffer, seen potentially from another device, without making an explicit copy of the contents. The underlying mechanism is typically implemented by the kernel or device driver, and may involve lazy caching of parts of the buffer contents on the destination device's memory. If a non-copy view is unsupported for the buffer on the given device, nullptr is returned. An error can be returned if some low-level operation fails (such as an out-of-memory condition).

ViewOrCopy

@ByVal
public static BufferResult ViewOrCopy(@SharedPtr
                                              ArrowBuffer source,
                                              @SharedPtr
                                              MemoryManager to)

\brief View or copy buffer Try to view buffer contents on the given MemoryManager's device, but fall back to copying if a no-copy view isn't supported.