@PublicAPI(usage = ACCESS)
    public JavaClasses importPackagesOf(Class<?>... classes) {
        return importPackagesOf(ImmutableSet.copyOf(classes));
    }
@Test
    public void imports_jdk_packages() {
        JavaClasses classes = new ClassFileImporter().importPackagesOf(File.class);

        assertThatTypes(classes).contain(File.class);
    }