我正在尝试将ScalaTest合并到我的Java项目中。用ScalaTests替换所有JUnit测试。一方面，我想检查Guice的Injector是否注入正确的类型。在Java中，我有这样的测试：

public class InjectorBehaviour {
    @Test
    public void shouldInjectCorrectTypes() {
        Injector injector = Guice.createInjector(new ModuleImpl());
        House house = injector.getInstance(House.class);

        assertTrue(house.door() instanceof WoodenDoor);
        assertTrue(house.window() instanceof BambooWindow);
        assertTrue(house.roof() instanceof SlateRoof);
    }
}

但是我在使用ScalaTest做同样的问题：

class InjectorSpec extends Spec {
    describe("An injector") {
        it("should inject the correct types") {
            val injector = Guice.createInjector(new ModuleImpl)
            val house = injector.getInstance(classOf[House])

            assert(house.door instanceof WoodenDoor)
            assert(house.window instanceof BambooWindow)
            assert(house.roof instanceof SlateRoof)
        }
    }
}

它抱怨说，价值instanceof是不是成员Door/ Window/
Roof。我不能instanceof在Scala中使用这种方式吗？