public Collection<String> getClassNames() {
        return classNames;
    }
@Test
    void testListAddressAndPetImport() throws Exception {

        PackageHeaderLoader packageHeaderLoader = getPackageHeaderLoader("org.test.Rambo", "org.test.Pet");

        Collection<String> classNames = packageHeaderLoader.getClassNames();

        assertThat(classNames.size()).isEqualTo(2);
        assertThat(classNames.contains("org.test.Rambo")).isTrue();
        assertThat(classNames.contains("org.test.Pet")).isTrue();
    }