RdfGraph class final

Represents an immutable RDF graph with triple pattern matching capabilities

An RDF graph is formally defined as a set of RDF triples. This class provides functionality for working with such graphs, including:

• Creating graphs from sets of triples
• Adding or removing triples (creating new graph instances)
• Merging graphs
• Querying triples based on patterns

The class is designed to be immutable for thread safety and to prevent accidental modification. All operations that would modify the graph return a new instance.

Example:

// Create a graph with some initial triples
final graph = RdfGraph(triples: [
  Triple(john, name, johnSmith),
  Triple(john, knows, jane)
]);

// Create a new graph with an additional triple
final updatedGraph = graph.withTriple(Triple(jane, name, janeSmith));

Constructors

RdfGraph.new({List<Triple> triples = const []})

Creates an immutable RDF graph from a list of triples

Properties

hashCode → int

Provides a consistent hash code for this graph based on its triples.

no setter, override

isEmpty → bool

Whether this graph contains any triples

no setter

isNotEmpty → bool

Whether this graph contains at least one triple

no setter

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

size → int

Number of triples in this graph

no setter

triples → List<Triple>

Get all triples in the graph

no setter

Methods

findTriples({RdfSubject? subject, RdfPredicate? predicate, RdfObject? object}) → List<Triple>

Find all triples matching the given pattern

getObjects(RdfSubject subject, RdfPredicate predicate) → List<RdfObject>

Get all objects for a given subject and predicate

getSubjects(RdfPredicate predicate, RdfObject object) → List<RdfSubject>

Get all subjects with a given predicate and object

merge(RdfGraph other) → RdfGraph

Merges this graph with another, producing a new graph

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

inherited

withoutMatching({RdfSubject? subject, RdfPredicate? predicate, RdfObject? object}) → RdfGraph

Creates a new graph by filtering out triples that match a pattern

withTriple(Triple triple) → RdfGraph

Creates a new graph with the specified triple added

withTriples(List<Triple> triples) → RdfGraph

Creates a new graph with all the specified triples added

Operators

operator ==(Object other) → bool

We are implementing equals ourselves instead of using equatable, because we want to compare the sets of triples, not the order

override

Static Methods

fromTriples(List<Triple> triples) → RdfGraph

Creates an RDF graph from a list of triples (factory constructor)