return null
        }

        List<String> changes = filterChangesToReport(oldClass, oldMethods)
        if (changes.isEmpty()) {
            return null
        }
        return acceptOrReject(c, changes, Violation.error(c, " methods removed in internal super class"))
    }

    private Set<CtMethod> collectAllPublicApiMethods(CtClass c) {
        Set<CtMethod> result = [] as Set
        collect(result, c)

    }

    @Override
    protected Violation checkSuperClassChanges(JApiClass apiClass, CtClass oldClass, CtClass newClass) {
        return acceptOrReject(apiClass.superclass, Violation.notBinaryCompatible(apiClass.superclass))
    }

                return violationError(member);
            }
        }
        return null;
    }

    private Violation violationError(JApiCompatibility member) {
        return acceptOrReject(member, Violation.error(member, "Is not annotated with @Incubating"));
    }

            }
            if (infixChanged) {
                changes.add(modifierChangeDetail("infix", newIsInfix))
            }
            return acceptOrReject(member, changes, Violation.error(member, "Breaking Kotlin modifier change"))
        }

        return null
    }

    private static String modifierChangeDetail(String modifier, boolean added) {

                if (isIncubating((JApiHasAnnotations) member)) {
                    return Violation.warning(member, "Changed public API (@Incubating)");
                }
            }
            return acceptOrReject(member, Violation.notBinaryCompatible(member));
        }
        return null;
    }

            return null
        }

        List<String> changes = filterChangesToReport(newClass, newInterfaces)
        if (changes.isEmpty()) {
            return null
        }
        return acceptOrReject(c, changes, Violation.error(c, " introduces internal or incubating interfaces"))
    }

    private Map<String, CtClass> collectImplementedInterfaces(CtClass c) {
        Map<String, CtClass> result = [:]

        if (shouldSkipViolationCheckFor(member) || getRepository().isSince(getCurrentVersion(), member)) {
            return null;
        }

        return acceptOrReject(member, Violation.error(member, SINCE_ERROR_MESSAGE + getCurrentVersion()));
    }

    private boolean shouldSkipViolationCheckFor(JApiCompatibility member) {
        return !isClassFieldConstructorOrMethod(member) ||

                warnings << "Return nullability changed from nullable to non-nullable"
            }
        }

        if (!errors.isEmpty()) {
            def changes = errors + warnings
            return acceptOrReject(member, changes, Violation.error(member, changes.join(" ")))
        }
        if (!warnings.isEmpty()) {
            return Violation.warning(member, warnings.join(" "))
        }
        return null
    }