Jython 2.7.4 · org.python.core.BufferProtocol · APIdia, the JavaDoc alternative

Interface marking an object as capable of exposing its internal state as a PyBuffer.

A few objects implement BufferProtocol (e.g. by inheritance) but cannot actually provide their value as a PyBuffer. These should throw ClassCastException, permitting the idiom:

    try (PyBuffer buf = ((BufferProtocol) obj).getBuffer(PyBUF.SIMPLE)) {
        ... // Do something with buf
    } catch (ClassCastException e) {
        ... // expected bytes object or buffer not obj.getType()
    }

The catch is executed identically whether the cause is the explicit cast of obj or getBuffer, and the try-with-resources releases the buffer if one was obtained.

Method Summary

Modifier and Type	Method and Description
public PyBuffer	Returns: exported buffer getBuffer(int specifying features demanded and the navigational capabilities of the consumer flags) Method by which the consumer requests the buffer from the exporter.

Method Detail

getBuffer back to summary

getBuffer	back to summary
public PyBuffer getBuffer(int flags) throws PyException, ClassCastException Method by which the consumer requests the buffer from the exporter. The consumer provides information on its ability to understand buffer navigation. Each consumer requesting a buffer in this way, when it has finished using it, should make a corresponding call to `PyBuffer#release()` on the buffer it obtained, or `PyBuffer#close()` using try-with-resources, since some objects alter their behaviour while buffers are exported. Parameters flags:int specifying features demanded and the navigational capabilities of the consumer Returns:PyBuffer exported buffer Exceptions PyException: `BufferError` when expectations do not correspond with the buffer ClassCastException: when the object only formally implements `BufferProtocol`

public PyBuffer getBuffer(int flags) throws PyException, ClassCastException

Method by which the consumer requests the buffer from the exporter. The consumer provides information on its ability to understand buffer navigation. Each consumer requesting a buffer in this way, when it has finished using it, should make a corresponding call to PyBuffer#release() on the buffer it obtained, or PyBuffer#close() using try-with-resources, since some objects alter their behaviour while buffers are exported.

Parameters

flags:int: specifying features demanded and the navigational capabilities of the consumer

Returns:PyBuffer

exported buffer

Exceptions

PyException:: BufferError when expectations do not correspond with the buffer
ClassCastException:: when the object only formally implements BufferProtocol

public Interface BufferProtocol

Method Summary

Method Detail