vitrio::file_image_reader_provider Class Reference

A provider that reads files. It opens each file through a format selector, every time it is asked for one. More...

#include <vitrio/file_image_reader_provider.hpp>

Inheritance diagram for vitrio::file_image_reader_provider:

Collaboration diagram for vitrio::file_image_reader_provider:

Public Member Functions
	file_image_reader_provider (std::shared_ptr< const image_file_read_format_selector > formats)
	Construct a provider opening through a format selector.
std::shared_ptr< const image_reader >	acquire (const std::string &key) override
	Get the reader a key names.
Public Member Functions inherited from vitrio::image_reader_provider
	image_reader_provider (const image_reader_provider &other)=delete
	image_reader_provider (image_reader_provider &&other)=delete
image_reader_provider &	operator= (const image_reader_provider &other)=delete
image_reader_provider &	operator= (image_reader_provider &&other)=delete

Detailed Description

A provider that reads files. It opens each file through a format selector, every time it is asked for one.

It keeps nothing: every reader it returns is newly opened through the format selector it was constructed with, so a key asked for twice is opened twice and the two readers are unrelated. With no capacity to size and no eviction, a file is opened exactly as often as it is asked for.

A key is handed to the selector as the path of the file.

See also

file_image_writer_provider

image_file_read_format_selector

Constructor & Destructor Documentation

file_image_reader_provider()

vitrio::file_image_reader_provider::file_image_reader_provider ( std::shared_ptr< const image_file_read_format_selector >  formats )

explicit

Construct a provider opening through a format selector.

Parameters

formats

The formats a file may be opened with.

Exceptions

std::invalid_argument

If formats is null.

Member Function Documentation

acquire()

std::shared_ptr< const image_reader > vitrio::file_image_reader_provider::acquire ( const std::string &  key )

overridevirtual

Get the reader a key names.

Shared ownership rather than a reference, so that a reader the provider stops keeping stays alive for as long as it is still read through.

Parameters

key	Key of the file to read, such as its path.

Returns

std::shared_ptr<const image_reader> The reader, never null.

Exceptions

image_file_error	If the file does not exist or can not be read.
unsupported_operation_error	If no format can read the file.
image_file_format_error	If the file is malformed or truncated.

Implements vitrio::image_reader_provider.

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The documentation for this class was generated from the following file:

• vitrio/file_image_reader_provider.hpp