RDF::Trine::Store::LanguagePreference - RDF Store proxy for filtering language tagged literals
This document describes RDF::Trine::Store::LanguagePreference version 1.019
use RDF::Trine::Store::LanguagePreference;
RDF::Trine::Store::LanguagePreference provides a RDF::Trine::Store API to filter the statements made available from some underlying store object based on a users' language preferences (e.g. coming from an Accept-Language HTTP header value).
Beyond the methods documented below, this class inherits methods from the RDF::Trine::Store class.
new ( $store, { $lang1 => $q1, $lang2 => $q2, ... } )
Returns a new storage object that will act as a proxy for the $store object, filtering language literals based on the expressed language preferences.
$store
new_with_config ( $hashref )
Returns a new storage object configured with a hashref with certain keys as arguments.
The storetype key must be LanguagePreference for this backend.
storetype
LanguagePreference
The following key must also be used:
store
A configuration hash for the underlying store object.
preferred_languages
A hash reference mapping language tags to quality values in the range [0, 1]. The referent may be changed between operations to change the set of preferred languages used in statement matching.
new_with_config ( \%config )
Returns a new RDF::Trine::Store object based on the supplied configuration hashref.
language_preferences
Returns a hash of the language preference quality values.
language_preference( $lang )
Return the quality value preference for the given language.
update_language_preference( $lang => $qvalue )
Update the quality value preference for the given language.
get_statements ( $subject, $predicate, $object [, $context] )
Returns a stream object of all statements matching the specified subject, predicate and objects. Any of the arguments may be undef to match any value.
count_statements ( $subject, $predicate, $object, $context )
Returns a count of all the statements matching the specified subject, predicate, object, and context. Any of the arguments may be undef to match any value.
qvalueForLanguage ( $language, \%cache )
Returns the q-value for $language based on the current language preference. %cache is used across multiple calls to this method for performance reasons.
$language
%cache
siteQValueForLanguage ( $language )
Returns an implementation-specific q-value preference for the given $language. This method may be overridden by subclasses to control the default preferred language.
availableLanguagesForStatement( $statement )
Returns a list of language tags that are available in the underlying store for the given statement object. For example, if $statement represented the triple:
$statement
dbpedia:Los_Angeles rdf:label "Los Angeles"@en
and the underlying store contains the triples:
dbpedia:Los_Angeles rdf:label "Los Angeles"@en dbpedia:Los_Angeles rdf:label "ロサンゼルス"@ja dbpedia:Los_Angeles rdf:label "Лос-Анджелес"@ru
then the return value would be ('en', 'ja', 'ru').
('en', 'ja', 'ru')
languagePreferenceAllowsStatement ( $statement, \%cache )
Returns true if the $statement is allowed by the current language preference. %cache is used across multiple calls to this method for performance reasons.
supports ( [ $feature ] )
If $feature is specified, returns true if the feature is supported by the store, false otherwise. If $feature is not specified, returns a list of supported features.
$feature
Please report any bugs or feature requests to through the GitHub web interface at https://github.com/kasei/perlrdf/issues.
Gregory Todd Williams <gwilliams@cpan.org>
<gwilliams@cpan.org>
Copyright (c) 2006-2012 Gregory Todd Williams. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
To install RDF::Trine, copy and paste the appropriate command in to your terminal.
cpanm
cpanm RDF::Trine
CPAN shell
perl -MCPAN -e shell install RDF::Trine
For more information on module installation, please visit the detailed CPAN module installation guide.