java – 如何使用Scala进行instanceof检查(测试)

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.有一次,我想检查Guice的Injector是否注入了正确的类型.在Java中,我有一个这样的测试：

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时遇到了同样的问题：

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)
        }
    }
}

它抱怨值instanceof不是Door / Window / Roof的成员.我不能在Scala中使用instanceof吗？

解决方法:

Scala不是Java. Scala只是没有运算符instanceof,而是有一个名为isinstanceOf [Type]的参数方法.

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