boolean (@NotNull PsiClass psiClass) { final Set<String> abstractNames = new HashSet<>(); final Set<String> defaultNames = new HashSet<>(); InheritanceUtil.processSupers(psiClass, true, psiClass1 -> { for (PsiMethod method : psiClass1.getMethods()) { if (isDefinitelyAbstractInterfaceMethod(method)) { abstractNames.add(method.getName()); } else if (method.hasModifierProperty(PsiModifier.DEFAULT)) { defaultNames.add(method.getName()); } } return true; }); abstractNames.removeAll(defaultNames); return abstractNames.size() > 1; }