public List<Property> getProperties() {
        return Collections.unmodifiableList(Arrays.asList(properties));
    }
@Test // JENKINS-26775
    public void sytheticMethodShouldNotBeExported() {
        Model<Impl> model = builder.get(Impl.class);
        assertEquals("Redundant properties discovered: " + model.getProperties(), 1, model.getProperties().size());
    }