Soprano  2.7.56
Signals | Public Member Functions | Protected Member Functions
Soprano::Model Class Reference

A Model is the central class in Soprano. It is a queryable collection of RDF quadruples, i.e statements. More...

#include <Soprano/Model>

+ Inheritance diagram for Soprano::Model:

List of all members.

Signals

void statementsAdded ()
void statementsRemoved ()
void statementAdded (const Soprano::Statement &statement)
void statementRemoved (const Soprano::Statement &statement)

Public Member Functions

virtual ~Model ()
virtual Error::ErrorCode addStatement (const Statement &statement)=0
Error::ErrorCode addStatement (const Node &subject, const Node &predicate, const Node &object, const Node &context=Node())
Error::ErrorCode addStatements (const QList< Statement > &statements)
virtual Error::ErrorCode removeStatement (const Statement &statement)=0
Error::ErrorCode removeStatement (const Node &subject, const Node &predicate, const Node &object, const Node &context=Node())
virtual Error::ErrorCode removeAllStatements (const Statement &statement)=0
Error::ErrorCode removeAllStatements (const Node &subject, const Node &predicate, const Node &object, const Node &context=Node())
Error::ErrorCode removeStatements (const QList< Statement > &statements)
Error::ErrorCode removeContext (const Node &)
Error::ErrorCode removeAllStatements ()
virtual StatementIterator listStatements (const Statement &partial) const =0
StatementIterator listStatements (const Node &subject, const Node &predicate, const Node &object, const Node &context=Node()) const
StatementIterator listStatements () const
StatementIterator listStatementsInContext (const Node &context) const
virtual NodeIterator listContexts () const =0
virtual QueryResultIterator executeQuery (const QString &query, Query::QueryLanguage language, const QString &userQueryLanguage=QString()) const =0
virtual bool containsAnyStatement (const Statement &statement) const =0
bool containsAnyStatement (const Node &subject, const Node &predicate, const Node &object, const Node &context=Node()) const
virtual bool containsStatement (const Statement &statement) const =0
bool containsStatement (const Node &subject, const Node &predicate, const Node &object, const Node &context=Node()) const
bool containsContext (const Node &context) const
virtual bool isEmpty () const =0
virtual int statementCount () const =0
virtual Error::ErrorCode write (QTextStream &os) const
virtual Node createBlankNode ()=0

Protected Member Functions

 Model ()

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. (If you are looking for a simple container for statements, see Graph.) There are basically two types of Models in Soprano:

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 danie.nosp@m.le.g.nosp@m.aldi@.nosp@m.gmai.nosp@m.l.com
Sebastian Trueg trueg.nosp@m.@kde.nosp@m..org

Definition at line 94 of file model.h.


Constructor & Destructor Documentation

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

Member Function Documentation

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

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.

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

Remove one statement. For removing statements with wildward matching see removeAllStatements().

Parameters:
statementThe 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::Client::SparqlModel, Soprano::Index::IndexFilterModel, Soprano::Util::ReadOnlyModel, Soprano::Client::DBusModel, Soprano::Util::MutexModel, Soprano::FilterModel, Soprano::Inference::InferenceModel, and 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::removeAllStatements ( const Statement statement) [pure virtual]

Remove all statements that match the partial statement. For removing one specific statement see removeStatement().

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

Implemented in Soprano::NRLModel, Soprano::Client::SparqlModel, Soprano::Index::IndexFilterModel, Soprano::Util::ReadOnlyModel, Soprano::Client::DBusModel, Soprano::FilterModel, Soprano::Inference::InferenceModel, Soprano::Util::MutexModel, Soprano::StorageModel, and 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:
subjectThe subject node to match. Can be empty as a wildcard.
predicateThe predicate node to match. Can be empty as a wildcard.
objectThe object node to match. Can be empty as a wildcard.
contextThe context node to match. Can be empty as a wildcard.

Reimplemented in Soprano::FilterModel.

Convenience method which removes all statements in statements.

Reimplemented in Soprano::Util::DummyModel.

Convenience method that removes all statements in the context.

Reimplemented in Soprano::Util::DummyModel.

Convenience method that clear the Model of all statements

Reimplemented in 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:
partialThe partial Statement to match.
Returns:
An iterator for all the matched Statements, on error an invalid iterator is returned.

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

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:
subjectThe subject node to match. Can be empty as a wildcard.
predicateThe predicate node to match. Can be empty as a wildcard.
objectThe object node to match. Can be empty as a wildcard.
contextThe 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.

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.

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.

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::Util::AsyncModel, Soprano::Client::SparqlModel, Soprano::FilterModel, Soprano::Client::DBusModel, Soprano::Util::MutexModel, Soprano::Util::DummyModel, and Soprano::Util::ReadOnlyModel.

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

query_api_disabled 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:
queryThe query to evaluate.
languageThe query language used to encode query.
userQueryLanguageIf 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::Util::AsyncModel, Soprano::Client::SparqlModel, Soprano::NRLModel, Soprano::Index::IndexFilterModel, Soprano::FilterModel, Soprano::Client::DBusModel, Soprano::Util::MutexModel, Soprano::Util::DummyModel, and Soprano::Util::ReadOnlyModel.

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

Check if the model contains certain statements.

Parameters:
statementA partially defined statement that serves as a pattern.
Returns:
true if the Model contains a Statement matching the given statement pattern.

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

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:
subjectThe subject node to match. Can be empty as a wildcard.
predicateThe predicate node to match. Can be empty as a wildcard.
objectThe object node to match. Can be empty as a wildcard.
contextThe context node to match. Can be empty as a wildcard.

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:
statementThe 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::Client::SparqlModel, Soprano::FilterModel, Soprano::Client::DBusModel, Soprano::Util::MutexModel, Soprano::Util::DummyModel, Soprano::Util::ReadOnlyModel, and Soprano::StorageModel.

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.

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

Convenience method which is based on containsAnyStatement

Reimplemented in Soprano::Util::DummyModel.

virtual bool Soprano::Model::isEmpty ( ) const [pure virtual]
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::Client::SparqlModel, Soprano::FilterModel, Soprano::Client::DBusModel, Soprano::Util::MutexModel, Soprano::Util::ReadOnlyModel, and Soprano::Util::DummyModel.

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.

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::Client::SparqlModel, Soprano::FilterModel, Soprano::Util::ReadOnlyModel, Soprano::Client::DBusModel, and Soprano::Util::DummyModel.

Emitted when new statements have been added to the model.

Implementations of this interface have to emit this signal.

Emitted when statements have been removed from the model.

Implementations of this interface have to emit this signal.

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.

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.

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