private static List<Boolean> typeParametersNullabilityOf(CtClass ctClass) {
        NullableClassTypeParametersVisitor visitor = new NullableClassTypeParametersVisitor()
        new ClassReader(byteCodeFrom(ctClass)).accept(visitor, 0)
        return visitor.typeParametersNullability
    }

    static class NullableClassTypeParametersVisitor extends ClassVisitor {

        List<Boolean> typeParametersNullability = []