### Question:
WSCXMLKnowledgeBase implements HierarchicalKnowledgeBase, Serializable { public boolean isSuperclass(Concept x, Concept y) { return this.superclasses.get(y).contains(x); } WSCXMLKnowledgeBase(InputStream xmlTaxonomyStream);  WSCXMLKnowledgeBase(String xmlTaxonomy);  WSCXMLKnowledgeBase(File xmlTaxonomyFile);  WSCXMLKnowledgeBase(); @Override Concept getConcept(String id); @Override Instance getInstance(String id); @Override Set<Concept> getSubclasses(Concept concept); @Override Set<Concept> getSuperclasses(Concept concept); boolean equivalent(Concept x, Concept y); boolean isSubclass(Concept x, Concept y); boolean isSuperclass(Concept x, Concept y); @Override Concept resolveInstance(Instance instance); Set<Instance> getInstances(Concept concept); Set<Concept> getConcepts(); Set<Instance> getInstances();  }### Answer:
@Test public void testIsSuperclass() throws Exception { Concept a = kb.getConcept("con983993996"); Concept b = kb.getConcept("con2025477491"); assertTrue(kb.isSuperclass(b,a)); assertFalse(kb.isSuperclass(a,b)); }