Class DatasetImpl

java.lang.Object

org.apache.commons.rdf.simple.DatasetImpl

All Implemented Interfaces:

AutoCloseable, Dataset, GraphLike<Quad>

final class DatasetImpl
extends Object
implements Dataset

A simple, memory-based implementation of Dataset.

Quads in the graph are kept in a Set.

All Stream operations are performed using parallel and unordered directives.

Field Summary

Fields

Modifier and Type	Field	Description
private final SimpleRDF	factory
private final Set<Quad>	quads
private static final int	TO_STRING_MAX

Constructor Summary

Constructors

Constructor	Description
DatasetImpl(SimpleRDF simpleRDF)

Method Summary

Modifier and Type	Method	Description
void	add(BlankNodeOrIRI graphName, BlankNodeOrIRI subject, IRI predicate, RDFTerm object)	Add a quad to the dataset, possibly mapping any of the components to those supported by this dataset.
void	add(Quad quad)	Add a quad to the dataset, possibly mapping any of the components of the Quad to those supported by this dataset.
void	clear()	Clear the dataset, removing all quads.
void	close()	Close the dataset, relinquishing any underlying resources.
boolean	contains(Optional<BlankNodeOrIRI> graphName, BlankNodeOrIRI subject, IRI predicate, RDFTerm object)	Check if dataset contains a pattern of quads.
boolean	contains(Quad quad)	Check if dataset contains quad.
Graph	getGraph()	Get the default graph of this dataset.
Optional<Graph>	getGraph(BlankNodeOrIRI graphName)	Get a named graph in this dataset.
Stream<BlankNodeOrIRI>	getGraphNames()	Get the graph names in this Dataset.
private Stream<Quad>	getQuads(Predicate<Quad> filter)
private <T extends RDFTerm> RDFTerm	internallyMap(T object)
void	remove(Optional<BlankNodeOrIRI> graphName, BlankNodeOrIRI subject, IRI predicate, RDFTerm object)	Remove a concrete pattern of quads from the default graph of the dataset.
void	remove(Quad quad)	Remove a concrete quad from the dataset.
long	size()	Number of quads contained by the dataset.
Stream<Quad>	stream()	Get all quads contained by the dataset.
Stream<Quad>	stream(Optional<BlankNodeOrIRI> graphName, BlankNodeOrIRI subject, IRI predicate, RDFTerm object)	Get all quads contained by the dataset matched with the pattern.
String	toString()

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface Dataset

iterate, iterate

Field Details

TO_STRING_MAX

private static final int TO_STRING_MAX

See Also:

• Constant Field Values

quads

private final Set<Quad> quads

factory

private final SimpleRDF factory

Constructor Details

DatasetImpl

DatasetImpl(SimpleRDF simpleRDF)

Method Details

add

public void add(BlankNodeOrIRI graphName,
 BlankNodeOrIRI subject,
 IRI predicate,
 RDFTerm object)

Description copied from interface: Dataset

Add a quad to the dataset, possibly mapping any of the components to those supported by this dataset.

Specified by:

add in interface Dataset

Parameters:

graphName - The graph the quad belongs to, or null for the default graph

subject - The quad subject

predicate - The quad predicate

object - The quad object

add

public void add(Quad quad)

Description copied from interface: Dataset

Add a quad to the dataset, possibly mapping any of the components of the Quad to those supported by this dataset.

Specified by:

add in interface Dataset

Specified by:

add in interface GraphLike<Quad>

Parameters:

quad - The quad to add

internallyMap

private <T extends RDFTerm> RDFTerm internallyMap(T object)

clear

public void clear()

Description copied from interface: Dataset

Clear the dataset, removing all quads.

Specified by:

clear in interface Dataset

Specified by:

clear in interface GraphLike<Quad>

contains

public boolean contains(Optional<BlankNodeOrIRI> graphName,
 BlankNodeOrIRI subject,
 IRI predicate,
 RDFTerm object)

Description copied from interface: Dataset

Check if dataset contains a pattern of quads.

Specified by:

contains in interface Dataset

Parameters:

graphName - The graph the quad belongs to, wrapped as an Optional (null is a wildcard, Optional.empty() is the default graph)

subject - The quad subject (null is a wildcard)

predicate - The quad predicate (null is a wildcard)

object - The quad object (null is a wildcard)

Returns:

True if the dataset contains any quads that match the given pattern.

contains

public boolean contains(Quad quad)

Description copied from interface: Dataset

Check if dataset contains quad.

Specified by:

contains in interface Dataset

Specified by:

contains in interface GraphLike<Quad>

Parameters:

quad - The quad to check.

Returns:

True if the dataset contains the given Quad.

stream

public Stream<Quad> stream()

Description copied from interface: Dataset

Get all quads contained by the dataset.

The iteration does not contain any duplicate quads, as determined by the Quad.equals(Object) method for each Quad.

The behaviour of the Stream is not specified if Dataset.add(Quad), Dataset.remove(Quad) or Dataset.clear() are called on the Dataset before it terminates.

Implementations may throw ConcurrentModificationException from Stream methods if they detect a conflict while the Stream is active.

Specified by:

stream in interface Dataset

Specified by:

stream in interface GraphLike<Quad>

Returns:

A Stream over all of the quads in the dataset

stream

public Stream<Quad> stream(Optional<BlankNodeOrIRI> graphName,
 BlankNodeOrIRI subject,
 IRI predicate,
 RDFTerm object)

Description copied from interface: Dataset

Get all quads contained by the dataset matched with the pattern.

The iteration does not contain any duplicate quads, as determined by the Quad.equals(Object) method for each Quad.

The behaviour of the Stream is not specified if Dataset.add(Quad), Dataset.remove(Quad) or Dataset.clear() are called on the Dataset before it terminates.

Implementations may throw ConcurrentModificationException from Stream methods if they detect a conflict while the Stream is active.

Specified by:

stream in interface Dataset

Parameters:

graphName - The graph the quad belongs to, wrapped as an Optional (null is a wildcard, Optional.empty() is the default graph)

subject - The quad subject (null is a wildcard)

predicate - The quad predicate (null is a wildcard)

object - The quad object (null is a wildcard)

Returns:

A Stream over the matched quads.

getQuads

private Stream<Quad> getQuads(Predicate<Quad> filter)

remove

public void remove(Optional<BlankNodeOrIRI> graphName,
 BlankNodeOrIRI subject,
 IRI predicate,
 RDFTerm object)

Description copied from interface: Dataset

Remove a concrete pattern of quads from the default graph of the dataset.

Specified by:

remove in interface Dataset

Parameters:

graphName - The graph the quad belongs to, wrapped as an Optional (null is a wildcard, Optional.empty() is the default graph)

subject - The quad subject (null is a wildcard)

predicate - The quad predicate (null is a wildcard)

object - The quad object (null is a wildcard)

remove

public void remove(Quad quad)

Description copied from interface: Dataset

Remove a concrete quad from the dataset.

Specified by:

remove in interface Dataset

Specified by:

remove in interface GraphLike<Quad>

Parameters:

quad - quad to remove

size

public long size()

Description copied from interface: Dataset

Number of quads contained by the dataset.

The count of a set does not include duplicates, consistent with the Quad.equals(Object) equals method for each Quad.

Specified by:

size in interface Dataset

Specified by:

size in interface GraphLike<Quad>

Returns:

The number of quads in the dataset

toString

public String toString()

Overrides:

toString in class Object

close

public void close()

Description copied from interface: Dataset

Close the dataset, relinquishing any underlying resources.

For example, this would close any open file and network streams and free database locks held by the dataset implementation.

The behaviour of the other dataset methods are undefined after closing the dataset.

Implementations might not need Dataset.close(), hence the default implementation does nothing.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Dataset

getGraph

public Graph getGraph()

Description copied from interface: Dataset

Get the default graph of this dataset.

The Triples of the default graph are equivalent to the Quads in this Dataset which has the Quad.getGraphName() set to Optional.empty().

It is unspecified if modifications to the returned Graph are reflected in this Dataset.

The returned graph MAY be empty.

Specified by:

getGraph in interface Dataset

Returns:

The default graph of this Dataset

See Also:

• Dataset.getGraph(BlankNodeOrIRI)

getGraph

public Optional<Graph> getGraph(BlankNodeOrIRI graphName)

Description copied from interface: Dataset

Get a named graph in this dataset.

The Triples of the named graph are equivalent to the the Quads of this Dataset which has the Quad.getGraphName() equal to the provided graphName, or equal to Optional.empty() if the provided graphName is null.

It is unspecified if modifications to the returned Graph are reflected in this Dataset.

It is unspecified if requesting an unknown or empty graph will return Optional.empty() or create a new empty Graph.

Specified by:

getGraph in interface Dataset

Parameters:

graphName - The name of the graph, or null for the default graph.

Returns:

The named Graph, or Optional.empty() if the dataset do not contain the named graph.

See Also:

• Dataset.getGraph()
• Dataset.getGraphNames()

getGraphNames

public Stream<BlankNodeOrIRI> getGraphNames()

Description copied from interface: Dataset

Get the graph names in this Dataset.

The set of returned graph names is equivalent to the set of unique Quad.getGraphName() of all the Dataset.stream() of this dataset (excluding the default graph).

The returned Stream SHOULD NOT contain duplicate graph names.

The graph names can be used with Dataset.getGraph(BlankNodeOrIRI) to retrieve the corresponding Graph, however callers should be aware of any concurrent modifications to the Dataset may cause such calls to return Optional.empty().

Note that a Dataset always contains a default graph which is not named, and thus is not represented in the returned Stream. The default graph is accessible via Dataset.getGraph() or by using Optional.empty() in the Quad access methods).

Specified by:

getGraphNames in interface Dataset

Returns:

A Stream of the graph names of this Dataset.