Modifier and Type	Class and Description
pack-priv static class	Strided1DWritableBuffer.SlicedView A `Strided1DWritableBuffer.SlicedView` represents a non-contiguous subsequence of a simple buffer.

Access	Constructor and Description
public	Strided1DWritableBuffer(int consumer requirements flags, BufferProtocol exporting object (or `null`) obj, byte[] raw byte array containing exported data storage, int index into storage of item[0] index0, int number of items in the slice count, int byte-index distance from one element to the next in the new PyBuffer stride) Provide an instance of `Strided1DWritableBuffer` on a particular array of bytes specifying a starting index, the number of items in the result, and a byte-indexing stride.

Method Summary

Modifier and Type	Method and Description
protected final void	checkWritable() Overrides org.python.core.buffer.BaseBuffer.checkWritable. Do nothing: the buffer is writable.
public PyBuffer	getBufferSlice(int specifying features demanded and the navigational capabilities of the consumer flags, int index in the current buffer start, int number of items in the required slice count, int index-distance in the current buffer between consecutive items in the slice stride) Overrides org.python.core.buffer.Strided1DBuffer.getBufferSlice. Implements org.python.core.PyBuffer.getBufferSlice. Get a `PyBuffer` that represents a slice of the current one described in terms of a start index, number of items to include in the slice, and the stride in the current buffer.
public final boolean	isReadonly() Overrides org.python.core.buffer.Strided1DBuffer.isReadonly. Implements org.python.core.PyBUF.isReadonly. Determine whether the consumer is entitled to write to the exported storage.
protected void	storeAtImpl(byte to store value, int byte-index of location to retrieve byteIndex) Overrides org.python.core.buffer.BaseArrayBuffer.storeAtImpl. Store the byte at the given index in the underlying storage treated as a flat sequence of bytes.

Inherited from org.python.core.buffer.Strided1DBuffer:: byteIndex getPointer getPointer

Constructor Detail

Strided1DWritableBuffer back to summary

Strided1DWritableBuffer	back to summary
public Strided1DWritableBuffer(int flags, BufferProtocol obj, byte[] storage, int index0, int count, int stride) throws ArrayIndexOutOfBoundsException, NullPointerException, PyException Provide an instance of `Strided1DWritableBuffer` on a particular array of bytes specifying a starting index, the number of items in the result, and a byte-indexing stride. The result of `byteAt(i)` will be equal to `storage[index0+stride*i]` (whatever the sign of `stride`), valid for 0≤`i`<`count`. The constructed `PyBuffer` meets the consumer's expectations as expressed in the `flags` argument, or an exception will be thrown if these are incompatible with the type (e.g. the consumer does not specify that it understands the strides array). Note that the actual range in the `storage` array, the lowest and highest index, is not explicitly passed, but is implicit in `index0`, `count` and `stride`. The caller is responsible for checking these fall within the array, or the sub-range the caller is allowed to use. Parameters flags:int consumer requirements obj:BufferProtocol exporting object (or `null`) storage:byte[] raw byte array containing exported data index0:int index into storage of item[0] count:int number of items in the slice stride:int byte-index distance from one element to the next in the new PyBuffer Exceptions ArrayIndexOutOfBoundsException: if `index0`, `count` and `stride` are inconsistent with `storage.length` NullPointerException: if `storage` is null PyException: `BufferError` when expectations do not correspond with the type

public Strided1DWritableBuffer(int flags, BufferProtocol obj, byte[] storage, int index0, int count, int stride) throws ArrayIndexOutOfBoundsException, NullPointerException, PyException

Provide an instance of Strided1DWritableBuffer on a particular array of bytes specifying a starting index, the number of items in the result, and a byte-indexing stride. The result of byteAt(i) will be equal to storage[index0+stride*i] (whatever the sign of stride), valid for 0≤i<count.

The constructed PyBuffer meets the consumer's expectations as expressed in the flags argument, or an exception will be thrown if these are incompatible with the type (e.g. the consumer does not specify that it understands the strides array). Note that the actual range in the storage array, the lowest and highest index, is not explicitly passed, but is implicit in index0, count and stride. The caller is responsible for checking these fall within the array, or the sub-range the caller is allowed to use.

Parameters

flags:int: consumer requirements
obj:BufferProtocol: exporting object (or null)
storage:byte[]: raw byte array containing exported data
index0:int: index into storage of item[0]
count:int: number of items in the slice
stride:int: byte-index distance from one element to the next in the new PyBuffer

Exceptions

ArrayIndexOutOfBoundsException:: if index0, count and stride are inconsistent with storage.length
NullPointerException:: if storage is null
PyException:: BufferError when expectations do not correspond with the type

Method Detail

checkWritable	back to summary
protected final void checkWritable() Overrides org.python.core.buffer.BaseBuffer.checkWritable. Do nothing: the buffer is writable. Annotations @Override

checkWritable

back to summary

protected final void checkWritable()

Overrides org.python.core.buffer.BaseBuffer.checkWritable.

Do nothing: the buffer is writable.

Annotations

@Override

getBufferSlice back to summary

getBufferSlice	back to summary
public PyBuffer getBufferSlice(int flags, int start, int count, int stride) Overrides org.python.core.buffer.Strided1DBuffer.getBufferSlice. Implements org.python.core.PyBuffer.getBufferSlice. Doc from org.python.core.buffer.Strided1DBuffer.getBufferSlice. Get a `PyBuffer` that represents a slice of the current one described in terms of a start index, number of items to include in the slice, and the stride in the current buffer. A consumer that obtains a `PyBuffer` with `getBufferSlice` must release it with `PyBuffer#release` just as if it had been obtained with `PyBuffer#getBuffer(int)` Suppose that x(i) denotes the ith element of the current buffer, that is, the byte retrieved by `this.byteAt(i)` or the unit indicated by `this.getPointer(i)`. A request for a slice where `start` = s, `count` = N and `stride` = m, results in a buffer y such that y(k) = x(s+km) where k=0..(N-1). In Python terms, this is the slice x[s : s+(N-1)m+1 : m] (if m>0) or the slice x[s : s+(N-1)m-1 : m] (if m<0). Implementations should check that this range is entirely within the current buffer. In a simple buffer backed by a contiguous byte array, the result is a strided PyBuffer on the same storage but where the offset is adjusted by s and the stride is as supplied. If the current buffer is already strided and/or has an item size larger than single bytes, the new `start` index, `count` and `stride` will be translated from the arguments given, through this buffer's stride and item size. The caller always expresses `start` and `strides` in terms of the abstract view of this buffer. `Strided1DBuffer` provides an implementation for slicing already-strided bytes in one dimension. In that case, x(i) = u(r+ip) for i = 0..L-1 where u is the underlying buffer, and r, p and L are the start, stride and count with which x was created from u. Thus y(k) = u(r+sp+kmp), that is, the composite `index0` is r+sp and the composite `stride` is mp. `Strided1DWritableBuffer` provides an implementation that returns a writable slice. Parameters flags:int Doc from org.python.core.PyBuffer.getBufferSlice. specifying features demanded and the navigational capabilities of the consumer start:int Doc from org.python.core.PyBuffer.getBufferSlice. index in the current buffer count:int Doc from org.python.core.PyBuffer.getBufferSlice. number of items in the required slice stride:int Doc from org.python.core.PyBuffer.getBufferSlice. index-distance in the current buffer between consecutive items in the slice Returns:PyBuffer Doc from org.python.core.PyBuffer.getBufferSlice. a buffer representing the slice Annotations @Override

public PyBuffer getBufferSlice(int flags, int start, int count, int stride)

Overrides org.python.core.buffer.Strided1DBuffer.getBufferSlice.

Implements org.python.core.PyBuffer.getBufferSlice.

Doc from org.python.core.buffer.Strided1DBuffer.getBufferSlice.

Get a PyBuffer that represents a slice of the current one described in terms of a start index, number of items to include in the slice, and the stride in the current buffer. A consumer that obtains a PyBuffer with getBufferSlice must release it with PyBuffer#release just as if it had been obtained with PyBuffer#getBuffer(int)

Suppose that x(i) denotes the ith element of the current buffer, that is, the byte retrieved by this.byteAt(i) or the unit indicated by this.getPointer(i). A request for a slice where start = s, count = N and stride = m, results in a buffer y such that y(k) = x(s+km) where k=0..(N-1). In Python terms, this is the slice x[s : s+(N-1)m+1 : m] (if m>0) or the slice x[s : s+(N-1)m-1 : m] (if m<0). Implementations should check that this range is entirely within the current buffer.

In a simple buffer backed by a contiguous byte array, the result is a strided PyBuffer on the same storage but where the offset is adjusted by s and the stride is as supplied. If the current buffer is already strided and/or has an item size larger than single bytes, the new start index, count and stride will be translated from the arguments given, through this buffer's stride and item size. The caller always expresses start and strides in terms of the abstract view of this buffer.

Strided1DBuffer provides an implementation for slicing already-strided bytes in one dimension. In that case, x(i) = u(r+ip) for i = 0..L-1 where u is the underlying buffer, and r, p and L are the start, stride and count with which x was created from u. Thus y(k) = u(r+sp+kmp), that is, the composite index0 is r+sp and the composite stride is mp.

Strided1DWritableBuffer provides an implementation that returns a writable slice.

Parameters

flags:int

Doc from org.python.core.PyBuffer.getBufferSlice.

specifying features demanded and the navigational capabilities of the consumer

start:int

Doc from org.python.core.PyBuffer.getBufferSlice.

index in the current buffer

count:int

Doc from org.python.core.PyBuffer.getBufferSlice.

number of items in the required slice

stride:int

Doc from org.python.core.PyBuffer.getBufferSlice.

index-distance in the current buffer between consecutive items in the slice

Returns:PyBuffer

Doc from org.python.core.PyBuffer.getBufferSlice.

a buffer representing the slice

Annotations

@Override

isReadonly back to summary

isReadonly	back to summary
public final boolean isReadonly() Overrides org.python.core.buffer.Strided1DBuffer.isReadonly. Implements org.python.core.PyBUF.isReadonly. Doc from org.python.core.PyBUF.isReadonly. Determine whether the consumer is entitled to write to the exported storage. Declared `final` returning `true` in `Strided1DWritableBuffer` to make checks unnecessary. Returns:boolean true if writing is not allowed, false if it is. Annotations @Override

public final boolean isReadonly()

Overrides org.python.core.buffer.Strided1DBuffer.isReadonly.

Implements org.python.core.PyBUF.isReadonly.

Doc from org.python.core.PyBUF.isReadonly.

Determine whether the consumer is entitled to write to the exported storage.

Declared final returning true in Strided1DWritableBuffer to make checks unnecessary.

Returns:boolean

true if writing is not allowed, false if it is.

Annotations

@Override

storeAtImpl back to summary

storeAtImpl	back to summary
protected void storeAtImpl(byte value, int byteIndex) Overrides org.python.core.buffer.BaseArrayBuffer.storeAtImpl. Doc from org.python.core.buffer.BaseBuffer.storeAtImpl. Store the byte at the given index in the underlying storage treated as a flat sequence of bytes. This byte-index will have been computed from the item index (which may have been multi-dimensional), taking into account `index0`, `shape`, `strides`, and the item size. The caller is responsible for validating the original item-index and raising (typically) an `IndexOutOfBoundsException`. Misuse of this method may still result in unchecked exceptions characteristic of the storage implementation. This method must implement the check for read-only character, raising a `BufferError` in the case of a violation. Parameters value:byte to store byteIndex:int byte-index of location to retrieve Annotations @Override

protected void storeAtImpl(byte value, int byteIndex)

Overrides org.python.core.buffer.BaseArrayBuffer.storeAtImpl.

Doc from org.python.core.buffer.BaseBuffer.storeAtImpl.

Store the byte at the given index in the underlying storage treated as a flat sequence of bytes. This byte-index will have been computed from the item index (which may have been multi-dimensional), taking into account index0, shape, strides, and the item size. The caller is responsible for validating the original item-index and raising (typically) an IndexOutOfBoundsException. Misuse of this method may still result in unchecked exceptions characteristic of the storage implementation. This method must implement the check for read-only character, raising a BufferError in the case of a violation.

Parameters

value:byte: to store
byteIndex:int: byte-index of location to retrieve

Annotations

@Override

org.python.core.buffer back to summary

pack-priv Class Strided1DWritableBuffer.SlicedView

Class Inheritance

extends Strided1DWritableBuffer

java.lang.Object
org.python.core.buffer.BaseBuffer
org.python.core.buffer.Base1DBuffer
org.python.core.buffer.BaseArrayBuffer
org.python.core.buffer.Strided1DBuffer
org.python.core.buffer.Strided1DWritableBuffer
org.python.core.buffer.Strided1DWritableBuffer.SlicedView

A Strided1DWritableBuffer.SlicedView represents a non-contiguous subsequence of a simple buffer.

Field Summary

Modifier and Type	Field and Description
pack-priv PyBuffer	root The buffer on which this is a slice view

Constructor Summary

Access	Constructor and Description
public	SlicedView(PyBuffer on which release must be called when this is released root, int consumer requirements flags, byte[] raw byte array containing exported data storage, int index into storage of item[0] index0, int number of items in the sliced view count, int in between successive elements of the new PyBuffer stride) Construct a slice of a one-dimensional byte buffer.

Method Summary

Modifier and Type	Method and Description
protected PyBuffer	getRoot() Overrides org.python.core.buffer.BaseBuffer.getRoot. Some `PyBuffer`s, those created by slicing a `PyBuffer`, are related to a root `PyBuffer`.

Inherited from org.python.core.buffer.Strided1DWritableBuffer:: checkWritable getBufferSlice isReadonly storeAtImpl

Field Detail

root	back to summary
pack-priv PyBuffer root The buffer on which this is a slice view

Constructor Detail

SlicedView back to summary

SlicedView	back to summary
public SlicedView(PyBuffer root, int flags, byte[] storage, int index0, int count, int stride) throws PyException Construct a slice of a one-dimensional byte buffer. Parameters root:PyBuffer on which release must be called when this is released flags:int consumer requirements storage:byte[] raw byte array containing exported data index0:int index into storage of item[0] count:int number of items in the sliced view stride:int in between successive elements of the new PyBuffer Exceptions PyException: `BufferError` when expectations do not correspond with the type

public SlicedView(PyBuffer root, int flags, byte[] storage, int index0, int count, int stride) throws PyException

Construct a slice of a one-dimensional byte buffer.

Parameters

root:PyBuffer: on which release must be called when this is released
flags:int: consumer requirements
storage:byte[]: raw byte array containing exported data
index0:int: index into storage of item[0]
count:int: number of items in the sliced view
stride:int: in between successive elements of the new PyBuffer

Exceptions

PyException:: BufferError when expectations do not correspond with the type

Method Detail

getRoot back to summary

getRoot	back to summary
protected PyBuffer getRoot() Overrides org.python.core.buffer.BaseBuffer.getRoot. Doc from org.python.core.buffer.BaseBuffer.getRoot. Some `PyBuffer`s, those created by slicing a `PyBuffer`, are related to a root `PyBuffer`. During creation of such a slice, we need to supply a value for this root. If the present object is not itself a slice, this root is the object itself; if the buffer is already a slice, it is the root it was given at creation time. Often this is the only difference between a slice-view and a directly-exported buffer. Override this method in slices to return the root buffer of the slice. Returns:PyBuffer this buffer (or the root buffer if this is a sliced view) Annotations @Override

protected PyBuffer getRoot()

Overrides org.python.core.buffer.BaseBuffer.getRoot.

Doc from org.python.core.buffer.BaseBuffer.getRoot.

Some PyBuffers, those created by slicing a PyBuffer, are related to a root PyBuffer. During creation of such a slice, we need to supply a value for this root. If the present object is not itself a slice, this root is the object itself; if the buffer is already a slice, it is the root it was given at creation time. Often this is the only difference between a slice-view and a directly-exported buffer. Override this method in slices to return the root buffer of the slice.

Returns:PyBuffer

this buffer (or the root buffer if this is a sliced view)

Annotations

@Override

public Class Strided1DWritableBuffer

Nested and Inner Type Summary

Field Summary

Constructor Summary

Method Summary

Constructor Detail

Method Detail

pack-priv Class Strided1DWritableBuffer.SlicedView

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail