org.eclipse.rdf4j.model.util

Class Statements

java.lang.Object

org.eclipse.rdf4j.model.util.Statements

public class Statements
extends Object

Utility methods for Statement objects.

Author:

Jeen Broekstra

Field Summary

Fields

Modifier and Type	Field and Description
static java.util.function.Function<Triple,Resource>	TRIPLE_BNODE_MAPPER A Function that maps Triple to BNode consistently.

Constructor Summary

Constructors

Constructor and Description
Statements()

Method Summary

Modifier and Type	Method and Description
static void	consume(ValueFactory vf, Resource subject, IRI predicate, Value object, java.util.function.Consumer<Statement> consumer, Resource... contexts) Creates one or more Statement objects with the given subject, predicate and object, one for each given context, and sends each created statement to the supplied Consumer.
static void	convertRDFStarToReification(Statement st, java.util.function.Consumer<Statement> consumer) Converts the supplied RDF* statement to RDF reification statements, and sends the resultant statements to the supplied consumer.
static void	convertRDFStarToReification(ValueFactory vf, java.util.function.Function<Triple,Resource> reifiedIdMapper, Statement st, java.util.function.Consumer<Statement> consumer) Converts the supplied RDF* statement to RDF reification statements, and sends the resultant statements to the supplied consumer.
static void	convertRDFStarToReification(ValueFactory vf, Statement st, java.util.function.Consumer<Statement> consumer) Converts the supplied RDF* statement to RDF reification statements, and sends the resultant statements to the supplied consumer.
static <C extends Collection<Statement>> C	create(ValueFactory vf, Resource subject, IRI predicate, Value object, C collection, Resource... contexts) Creates one or more Statement objects with the given subject, predicate and object, one for each given context.
static boolean	isSameTriple(Statement st1, Statement st2) Checks if the two statements represent the same triple (that is, they have equal subject, predicate, and object).
static Statement	stripContext(Statement statement) Strips the context (if any) from the supplied statement and returns a statement with the same subject, predicate and object, but with no assigned context.
static Statement	stripContext(ValueFactory vf, Statement statement) Strips the context (if any) from the supplied statement and returns a statement with the same subject, predicate and object, but with no assigned context.

Methods inherited from class java.lang.Object

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

Field Detail

TRIPLE_BNODE_MAPPER

@Experimental
public static java.util.function.Function<Triple,Resource> TRIPLE_BNODE_MAPPER

A Function that maps Triple to BNode consistently. Multiple invocations for the same Triple will return the same BNode. The current implementation creates a BNode by encoding the string representation of the Triple using base64 URL-safe encoding.

Constructor Detail

Statements

public Statements()

Method Detail

consume

public static void consume(ValueFactory vf,
                           Resource subject,
                           IRI predicate,
                           Value object,
                           java.util.function.Consumer<Statement> consumer,
                           Resource... contexts)

Creates one or more Statement objects with the given subject, predicate and object, one for each given context, and sends each created statement to the supplied Consumer. If no context is supplied, only a single statement (without any assigned context) is created.

Parameters:

vf - the ValueFactory to use for creating statements.

subject - the subject of each statement. May not be null.

predicate - the predicate of each statement. May not be null.

object - the object of each statement. May not be null.

consumer - the Consumer function for the produced statements.

contexts - the context(s) for which to produce statements. This argument is an optional vararg: leave it out completely to produce a single statement without context.

create

public static <C extends Collection<Statement>> C create(ValueFactory vf,
                                                         Resource subject,
                                                         IRI predicate,
                                                         Value object,
                                                         C collection,
                                                         Resource... contexts)

Creates one or more Statement objects with the given subject, predicate and object, one for each given context. If no context is supplied, only a single statement (without any assigned context) is created.

Parameters:

vf - the ValueFactory to use for creating statements.

subject - the subject of each statement. May not be null.

predicate - the predicate of each statement. May not be null.

object - the object of each statement. May not be null.

collection - the collection of Statements to which the newly created Statements will be added. May not be null.

contexts - the context(s) for which to produce statements. This argument is an optional vararg: leave it out completely to produce a single statement without context.

Returns:

the input collection of Statements, with the newly created Statements added.

stripContext

public static Statement stripContext(Statement statement)

Strips the context (if any) from the supplied statement and returns a statement with the same subject, predicate and object, but with no assigned context.

Parameters:

statement - the statement to strip the context from

Returns:

a statement without context

Since:

3.1.0

stripContext

public static Statement stripContext(ValueFactory vf,
                                     Statement statement)

Strips the context (if any) from the supplied statement and returns a statement with the same subject, predicate and object, but with no assigned context.

Parameters:

vf - the ValueFactory to use for creating a new Statement.

statement - the statement to strip the context from.

Returns:

a statement without context

Since:

3.1.0

isSameTriple

public static boolean isSameTriple(Statement st1,
                                   Statement st2)

Checks if the two statements represent the same triple (that is, they have equal subject, predicate, and object). Context information is disregarded.

Parameters:

st1 - the first statement to compare. May not be null.

st2 - the second statement to compare. May not be null.

Returns:

true iff the subject, predicate and object of st1 and st2 are equal, false otherwise.

Since:

2.0

See Also:

Statement.equals(Object)

convertRDFStarToReification

@Experimental
public static void convertRDFStarToReification(Statement st,
                                                             java.util.function.Consumer<Statement> consumer)

Converts the supplied RDF* statement to RDF reification statements, and sends the resultant statements to the supplied consumer. If the supplied statement is not RDF* it will be sent to the consumer as is.

The statements needed to represent reification will use blank nodes.

Parameters:

st - the Statement to convert.

consumer - the Consumer function for the produced statements.

convertRDFStarToReification

@Experimental
public static void convertRDFStarToReification(ValueFactory vf,
                                                             Statement st,
                                                             java.util.function.Consumer<Statement> consumer)

Converts the supplied RDF* statement to RDF reification statements, and sends the resultant statements to the supplied consumer. If the supplied statement is not RDF* it will be sent to the consumer as is.

The statements needed to represent reification will use blank nodes.

The supplied value factory is used to create all new statements and blank nodes.

Parameters:

vf - the ValueFactory to use for creating statements.

st - the Statement to convert.

consumer - the Consumer function for the produced statements.

convertRDFStarToReification

@Experimental
public static void convertRDFStarToReification(ValueFactory vf,
                                                             java.util.function.Function<Triple,Resource> reifiedIdMapper,
                                                             Statement st,
                                                             java.util.function.Consumer<Statement> consumer)

Converts the supplied RDF* statement to RDF reification statements, and sends the resultant statements to the supplied consumer. If the supplied statement is not RDF* it will be sent to the consumer as is.

The supplied value factory is used to create all new statements.

The supplied mapper function maps a Triple to a Resource and is used to create the ID of the RDF reification statement corresponding to the converted triple. The function must return the same value for identical triples in order to produce consistent results between invocations. See TRIPLE_BNODE_MAPPER.

Parameters:

vf - the ValueFactory to use for creating statements.

reifiedIdMapper - the mapper Function from Triple to Resource.

st - the Statement to convert,

consumer - the Consumer function for the produced statements.