soprano

Soprano::Model

Soprano::Model Class Reference

#include <Soprano/Model>

Inheritance diagram for Soprano::Model:

[legend]

List of all members.

Detailed Description

A Model is the central class in Soprano.

It is a queryable collection of RDF quadruples, i.e statements.

Model itself is just an interface for numerous implementations. There are basically two types of Models in Soprano:

StorageModel is the base class for Model implementations that actually store RDF quadruples. StorageModels are created transparently by Soprano backend plugins: Backend::createModel()
FilterModel is the base class for all filter models. FilterModels can be stacked on top of a StorageModel to perform arbitrary tasks like inference or actual content filtering. An important FilterModel is Inference::InferenceModel.

The simplest way to create a memory Model is to use the default Backend:

 Model* memModel = Soprano::createModel();

Error handling:

Model is based on Soprano's own error handling system which tries to emulate exceptions to a certain extend. Most methods in Model have a means of reporting if an operation was successful or not. For additional error information Model inherits ErrorCache which provides the method lastError().

Thus, advanced error handling would look as follows:

 Soprano::Model* model = Soprano::createModel();
 Soprano::Statement invalidStatement;
 if( model->addStatement( invalidStatement ) != Error::ErrorNone ) {
    showErrorMessage( model->lastError().message() );
 }

For this to work properly Model implementations have to reset the error in each method by either calling clearError() or setError().

See also:: Error handling in Soprano

Model is thread-safe when used with a thread-safe backend (all "official" Soprano backends are thread-safe). However, it is recommended to create Model instances in the main thread.

Author:: Daniele Galdi <daniele.galdi@gmail.com>
Sebastian Trueg <trueg@kde.org>

Definition at line 94 of file model.h.


Signals
void	statementAdded (const Soprano::Statement &statement)
void	statementRemoved (const Soprano::Statement &statement)
void	statementsAdded ()
void	statementsRemoved ()
Public Member Functions
virtual	~Model ()

Error::ErrorCode	addStatement (const Node &subject, const Node &predicate, const Node &object, const Node &context=Node())
virtual Error::ErrorCode	addStatement (const Statement &statement)=0
Error::ErrorCode	addStatements (const QList< Statement > &statements)

bool	containsAnyStatement (const Node &subject, const Node &predicate, const Node &object, const Node &context=Node()) const
virtual bool	containsAnyStatement (const Statement &statement) const =0
bool	containsContext (const Node &context) const
bool	containsStatement (const Node &subject, const Node &predicate, const Node &object, const Node &context=Node()) const
virtual bool	containsStatement (const Statement &statement) const =0
virtual bool	isEmpty () const =0
virtual int	statementCount () const =0

virtual Node	createBlankNode ()=0

virtual QueryResultIterator	executeQuery (const QString &query, Query::QueryLanguage language, const QString &userQueryLanguage=QString()) const =0
virtual NodeIterator	listContexts () const =0
StatementIterator	listStatements () const
StatementIterator	listStatements (const Node &subject, const Node &predicate, const Node &object, const Node &context=Node()) const
virtual StatementIterator	listStatements (const Statement &partial) const =0
StatementIterator	listStatementsInContext (const Node &context) const

Error::ErrorCode	removeAllStatements ()
Error::ErrorCode	removeAllStatements (const Node &subject, const Node &predicate, const Node &object, const Node &context=Node())
virtual Error::ErrorCode	removeAllStatements (const Statement &statement)=0
Error::ErrorCode	removeContext (const Node &)
Error::ErrorCode	removeStatement (const Node &subject, const Node &predicate, const Node &object, const Node &context=Node())
virtual Error::ErrorCode	removeStatement (const Statement &statement)=0
Error::ErrorCode	removeStatements (const QList< Statement > &statements)

virtual Error::ErrorCode	write (QTextStream &os) const
Protected Member Functions
	Model ()

Constructor & Destructor Documentation

virtual Soprano::Model::~Model ( ) [virtual]

Soprano::Model::Model ( ) [protected]

Member Function Documentation

Error::ErrorCode Soprano::Model::addStatement	(	const Node &	subject,
		const Node &	predicate,
		const Node &	object,
		const Node &	context = `Node()`
	)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Reimplemented in Soprano::FilterModel, and Soprano::Util::DummyModel.

virtual Error::ErrorCode Soprano::Model::addStatement ( const Statement & statement ) [pure virtual]

Add the Statement to the Model.

Parameters:

statement

The Statement to add.

Implemented in Soprano::FilterModel, Soprano::NRLModel, Soprano::Util::DummyModel, Soprano::Util::MutexModel, Soprano::Util::ReadOnlyModel, Soprano::Inference::InferenceModel, Soprano::Index::IndexFilterModel, and Soprano::Client::DBusModel.

Error::ErrorCode Soprano::Model::addStatements ( const QList< Statement > & statements )

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Reimplemented in Soprano::Util::DummyModel.

bool Soprano::Model::containsAnyStatement	(	const Node &	subject,
		const Node &	predicate,
		const Node &	object,
		const Node &	context = `Node()`
	)			const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Parameters:

	subject	The subject node to match. Can be empty as a wildcard.
	predicate	The predicate node to match. Can be empty as a wildcard.
	object	The object node to match. Can be empty as a wildcard.
	context	The context node to match. Can be empty as a wildcard.

Reimplemented in Soprano::FilterModel, and Soprano::Util::DummyModel.

virtual bool Soprano::Model::containsAnyStatement ( const Statement & statement ) const [pure virtual]

Check if the model contains certain statements.

Parameters:

statement

A partially defined statement that serves as a pattern.

Returns:: true if the Model contains a Statement matching the given statement pattern.

Implemented in Soprano::FilterModel, Soprano::StorageModel, Soprano::Util::DummyModel, Soprano::Util::MutexModel, Soprano::Util::ReadOnlyModel, and Soprano::Client::DBusModel.

bool Soprano::Model::containsContext ( const Node & context ) const

Convenience method which is based on containsAnyStatement.

Reimplemented in Soprano::Util::DummyModel.

bool Soprano::Model::containsStatement	(	const Node &	subject,
		const Node &	predicate,
		const Node &	object,
		const Node &	context = `Node()`
	)			const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Reimplemented in Soprano::FilterModel, and Soprano::Util::DummyModel.

virtual bool Soprano::Model::containsStatement ( const Statement & statement ) const [pure virtual]

Check if the model contains a statements.

Parameters:

statement

The statement in question. This has to be a valid statement, i.e. subject, predicate, and object need to be defined. If the context node is empty the default graph is searched.

Returns:: true if the Model contains the Statement, false otherwise or is statement is invalid.

Implemented in Soprano::FilterModel, Soprano::StorageModel, Soprano::Util::DummyModel, Soprano::Util::MutexModel, Soprano::Util::ReadOnlyModel, and Soprano::Client::DBusModel.

virtual Node Soprano::Model::createBlankNode ( ) [pure virtual]

Creates a new blank node with a unique identifier.

Returns:: A blank node that can be used to create new statements.

Implemented in Soprano::FilterModel, Soprano::Util::DummyModel, Soprano::Util::ReadOnlyModel, and Soprano::Client::DBusModel.

virtual QueryResultIterator Soprano::Model::executeQuery	(	const QString &	query,
		Query::QueryLanguage	language,
		const QString &	userQueryLanguage = `QString()`
	)			const `[pure virtual]`

Execute the given query over the Model.

This is a const read-only method. As such Model implementations should not support SPARQL extensions such as INSERT or UPDATE through this method. A future version of Soprano will provide an additional API for queries that change the Model.

Parameters:

	query	The query to evaluate.
	language	The query language used to encode `query`.
	userQueryLanguage	If `language` equals Query::QueryLanguageUser userQueryLanguage defines the language to use.

Returns:: An iterator over all results matching the query, on error an invalid iterator is returned.

Implemented in Soprano::FilterModel, Soprano::Util::DummyModel, Soprano::Util::MutexModel, Soprano::Util::ReadOnlyModel, Soprano::Index::IndexFilterModel, and Soprano::Client::DBusModel.

virtual bool Soprano::Model::isEmpty ( ) const [pure virtual]

Returns:: true if the Model doesn't contains any Statement.

Implemented in Soprano::FilterModel, Soprano::StorageModel, Soprano::Util::DummyModel, Soprano::Util::MutexModel, Soprano::Util::ReadOnlyModel, and Soprano::Client::DBusModel.

virtual NodeIterator Soprano::Model::listContexts ( ) const [pure virtual]

List all contexts in the model, i.e.

all named graphs.

Returns:: An iterator over context Nodes, on error an invalid iterator is returned.

Implemented in Soprano::FilterModel, Soprano::Util::DummyModel, Soprano::Util::MutexModel, Soprano::Util::ReadOnlyModel, and Soprano::Client::DBusModel.

StatementIterator Soprano::Model::listStatements ( ) const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Returns:: An iterator for all statements in the model, on error an invalid iterator is returned.

Reimplemented in Soprano::Util::DummyModel.

StatementIterator Soprano::Model::listStatements	(	const Node &	subject,
		const Node &	predicate,
		const Node &	object,
		const Node &	context = `Node()`
	)			const

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Parameters:

	subject	The subject node to match. Can be empty as a wildcard.
	predicate	The predicate node to match. Can be empty as a wildcard.
	object	The object node to match. Can be empty as a wildcard.
	context	The context node to match. Can be empty as a wildcard.

Returns:: An iterator for all the matched Statements, on error an invalid iterator is returned.

Reimplemented in Soprano::FilterModel, and Soprano::Util::DummyModel.

virtual StatementIterator Soprano::Model::listStatements ( const Statement & partial ) const [pure virtual]

Return an iterator over Model Statements that "partial" match the input Statement.

Parameters:

partial

The partial Statement to match.

Returns:: An iterator for all the matched Statements, on error an invalid iterator is returned.

Implemented in Soprano::FilterModel, Soprano::Util::DummyModel, Soprano::Util::MutexModel, Soprano::Util::ReadOnlyModel, and Soprano::Client::DBusModel.

StatementIterator Soprano::Model::listStatementsInContext ( const Node & context ) const

Convenience method which lists all statements in context.

Returns:: An iterator for all the matched Statements, on error an invalid iterator is returned.

Reimplemented in Soprano::Util::DummyModel.

Error::ErrorCode Soprano::Model::removeAllStatements ( )

Convenience method that clear the Model of all statements.

Reimplemented in Soprano::Util::DummyModel.

Error::ErrorCode Soprano::Model::removeAllStatements	(	const Node &	subject,
		const Node &	predicate,
		const Node &	object,
		const Node &	context = `Node()`
	)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Parameters:

	subject	The subject node to match. Can be empty as a wildcard.
	predicate	The predicate node to match. Can be empty as a wildcard.
	object	The object node to match. Can be empty as a wildcard.
	context	The context node to match. Can be empty as a wildcard.

Reimplemented in Soprano::FilterModel.

virtual Error::ErrorCode Soprano::Model::removeAllStatements ( const Statement & statement ) [pure virtual]

Remove all statements that match the partial statement.

For removing one specific statement see removeStatement().

Parameters:

statement

A possible partially defined statement that serves as a filter for all statements that should be removed.

Implemented in Soprano::FilterModel, Soprano::StorageModel, Soprano::Util::DummyModel, Soprano::Util::MutexModel, Soprano::Util::ReadOnlyModel, Soprano::Inference::InferenceModel, Soprano::Index::IndexFilterModel, and Soprano::Client::DBusModel.

Error::ErrorCode Soprano::Model::removeContext ( const Node & )

Convenience method that removes all statements in the context.

Reimplemented in Soprano::Util::DummyModel.

Error::ErrorCode Soprano::Model::removeStatement	(	const Node &	subject,
		const Node &	predicate,
		const Node &	object,
		const Node &	context = `Node()`
	)

This is an overloaded member function, provided for convenience. It differs from the above function only in what argument(s) it accepts.

Reimplemented in Soprano::FilterModel, and Soprano::Util::DummyModel.

virtual Error::ErrorCode Soprano::Model::removeStatement ( const Statement & statement ) [pure virtual]

Remove one statement.

For removing statements with wildward matching see removeAllStatements().

Parameters:

statement

The statement that should be removed. This has to be a valid statement.

Returns:: Error::ErrorNone on success and an error code if statement was invalid or an error occured.

Implemented in Soprano::FilterModel, Soprano::Util::DummyModel, Soprano::Util::MutexModel, Soprano::Util::ReadOnlyModel, Soprano::Inference::InferenceModel, Soprano::Index::IndexFilterModel, and Soprano::Client::DBusModel.

Error::ErrorCode Soprano::Model::removeStatements ( const QList< Statement > & statements )

Convenience method which removes all statements in statements.

Reimplemented in Soprano::Util::DummyModel.

void Soprano::Model::statementAdded ( const Soprano::Statement & statement ) [signal]

Notification signal for new statements.

Model implementations should emit this signal for each newly added statement.

virtual int Soprano::Model::statementCount ( ) const [pure virtual]

The number of statements stored in this Model.

Returns:: The size of the Model, or -1 on error.

Implemented in Soprano::FilterModel, Soprano::Util::DummyModel, Soprano::Util::MutexModel, Soprano::Util::ReadOnlyModel, and Soprano::Client::DBusModel.

void Soprano::Model::statementRemoved ( const Soprano::Statement & statement ) [signal]

Notification signal for removed statements.

Model implementations should emit this signal for each removed statement.

Warning:: Backends may choose not to emit this signal for each removed statement but only for a statement pattern (i.e. an invalid statement as used in removeAllStatements()) to prevent massive performance loss.

void Soprano::Model::statementsAdded ( ) [signal]

Emitted when new statements have been added to the model.

Implementations of this interface have to emit this signal.

void Soprano::Model::statementsRemoved ( ) [signal]

Emitted when statements have been removed from the model.

Implementations of this interface have to emit this signal.

virtual Error::ErrorCode Soprano::Model::write ( QTextStream & os ) const [virtual]

Write all statements in this Model to os.

Default implementation is based on Model::listStatements

Reimplemented in Soprano::FilterModel, and Soprano::Util::DummyModel.

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

model.h

soprano

Soprano::Model Class Reference

Detailed Description

Signals

Public Member Functions

Protected Member Functions

Constructor & Destructor Documentation

Member Function Documentation

soprano

API Reference