What might cause myOntology.writeAll(outStream, "RDF/XML");
(where myOntology is an OntModel) to get a stack overflow java.lang.StackOverflowError at java.util.regex.Pattern$GroupHead.match(Unknown Source) at java.util.regex.Pattern$BmpCharProperty.match(Unknown Source) ....... at org.apache.jena.iri.impl.Parser.<init>(Parser.java:90) at org.apache.jena.iri.impl.IRIImpl.<init>(IRIImpl.java:65) at org.apache.jena.iri.impl.AbsIRIFactoryImpl.create(AbsIRIFactoryImpl.java:40) at org.apache.jena.iri.impl.IRIFactoryImpl.create(IRIFactoryImpl.java:264) at org.apache.jena.riot.system.PrefixMapStd.add(PrefixMapStd.java:69) at java.util.HashMap.forEach(Unknown Source) at org.apache.jena.riot.system.PrefixMapBase.putAll(PrefixMapBase.java:76) Changing "writeAll" to "write" works fine.