Given the ontology:

Prefix(:=<file:/c/test.owl#>)
Prefix(a:=<file:/c/test.owl#>)
Prefix(rdfs:=<http://www.w3.org/2000/01/rdf-schema#>)
Prefix(owl2xml:=<http://www.w3.org/2006/12/owl2-xml#>)
Prefix(test:=<file:/c/test.owl#>)
Prefix(owl:=<http://www.w3.org/2002/07/owl#>)
Prefix(xsd:=<http://www.w3.org/2001/XMLSchema#>)
Prefix(rdf:=<http://www.w3.org/1999/02/22-rdf-syntax-ns#>)
Ontology(<file:/c/test.owl>
SubClassOf( owl:Thing ObjectOneOf( :ind ) )
ClassAssertion(:A :i)
)

we should have that

reasoner.getEquivalentClasses(dataFactory.getOWLClass(IRI.create("file:/c/test.o
wl#D")));

returns a Node, but NullPointerException is thrown instead.


This was discovered when using HermiT JUnit tests to test the correctness of 
the HermiT+ELK reasoner.

The stack traces from those tests which lead to the NullPointerException have 
been attached.

The test ontology as a file is also attached, as is a Java file implementing 
the above test case.