Loading ontology fails with NullPointerException [5.5.1]

[poojashah24]

I'm trying to load an OWL file using the snippet below -

OWLOntology ontology = manager.loadOntologyFromOntologyDocument(new File("file_name.owl"));

Stack trace -
Exception in thread "main" java.lang.NullPointerException
at uk.ac.manchester.cs.owl.owlapi.OWLOntologyFactoryImpl.loadOWLOntology(OWLOntologyFactoryImpl.java:186)
at uk.ac.manchester.cs.owl.owlapi.OWLOntologyManagerImpl.load(OWLOntologyManagerImpl.java:1105)
at uk.ac.manchester.cs.owl.owlapi.OWLOntologyManagerImpl.loadOntology(OWLOntologyManagerImpl.java:1055)
at uk.ac.manchester.cs.owl.owlapi.OWLOntologyManagerImpl.loadOntologyFromOntologyDocument(OWLOntologyManagerImpl.java:1005)
at uk.ac.manchester.cs.owl.owlapi.OWLOntologyManagerImpl.loadOntologyFromOntologyDocument(OWLOntologyManagerImpl.java:1018)
at Main.main(Main.java:19)

Dependencies -

caffeine-3.1.8.jar
commons-io-2.15.1.jar
commons-rdf-api-0.5.0.jar
guava-33.0.0-jre.jar
hppcrt-0.7.5.jar
jackson-annotations-2.16.1.jar
jackson-core-2.16.1.jar
jackson-databind-2.16.1.jar
jakarta.inject-api-2.0.1.jar
javax.inject-1.jar
jcl-over-slf4j-2.0.11.jar
jsonld-java-0.13.6.jar
jsr305-3.0.2.jar
owlapi-api-5.5.1.jar
owlapi-apibinding-5.5.1.jar
owlapi-compatibility-5.5.1.jar
owlapi-distribution-5.5.1.jar
owlapi-impl-5.5.1.jar
owlapi-parsers-5.5.1.jar
owlapi-rio-5.5.1.jar
owlapi-tools-5.5.1.jar
rdf4j-model-5.0.2.jar
rdf4j-model-api-5.0.2.jar
rdf4j-model-vocabulary-5.0.2.jar
rdf4j-rio-api-5.0.2.jar
rdf4j-rio-binary-5.0.2.jar
rdf4j-rio-datatypes-5.0.2.jar
rdf4j-rio-jsonld-5.0.2.jar
rdf4j-rio-languages-5.0.2.jar
rdf4j-rio-n3-5.0.2.jar
rdf4j-rio-nquads-5.0.2.jar
rdf4j-rio-ntriples-5.0.2.jar
rdf4j-rio-rdfjson-5.0.2.jar
rdf4j-rio-rdfxml-5.0.2.jar
rdf4j-rio-trig-5.0.2.jar
rdf4j-rio-trix-5.0.2.jar
rdf4j-rio-turtle-5.0.2.jar
slf4j-api-2.0.11.jar
xz-1.9.jar

I've been able to load this using owlapi 4.1.0 successfully. I tried a few different files but none of them, including pizza.owl, work.

[ignazio1977]

I can't replicate the failure.
The code where the exception is being thrown refers only local variables that cannot be null, unless the problem is the set of parser factories:

    Set<String> bannedParsers =
        new HashSet<>(Arrays.asList(configuration.getBannedParsers().split(" ")));
    PriorityCollection<OWLParserFactory> parsers =
        getParsers(documentSource, manager.getOntologyParsers());
    // use the selection of parsers to set the accept headers explicitly, including weights
    if (documentSource.getAcceptHeaders().isPresent()) {
        documentSource.setAcceptHeaders(AcceptHeaderBuilder.headersFromParsers(parsers));
    }
    for (OWLParserFactory parserFactory : parsers) {
line 186:        if (!bannedParsers.contains(parserFactory.getClass().getName())) {

Your classpath includes owlapi-distribution as well as owlapi-apibinding, which means you're likely to have two copies of the same classes and of the parsers configuration resource. That might be where the problem originates.

Try removing owlapi-distribution from the classpath.

[poojashah24]

Thanks! Doing that results in a NullPointerException

Exception in thread "main" java.lang.NullPointerException
	at uk.ac.manchester.cs.owl.owlapi.OWLOntologyFactoryImpl.loadOWLOntology(OWLOntologyFactoryImpl.java:186)
	at uk.ac.manchester.cs.owl.owlapi.OWLOntologyManagerImpl.load(OWLOntologyManagerImpl.java:1105)
	at uk.ac.manchester.cs.owl.owlapi.OWLOntologyManagerImpl.loadOntology(OWLOntologyManagerImpl.java:1055)
	at uk.ac.manchester.cs.owl.owlapi.OWLOntologyManagerImpl.loadOntologyFromOntologyDocument(OWLOntologyManagerImpl.java:1005)
	at uk.ac.manchester.cs.owl.owlapi.OWLOntologyManagerImpl.loadOntologyFromOntologyDocument(OWLOntologyManagerImpl.java:1018)
	at Main.main(Main.java:20)