guice注入器getInstance带注释的单例实例

Question

我正在使用Restlet和Guice。

CachedThreadPool在我的Guice中被定义：

@Provides
@Singleton
@Named("name0")
public ExecutorService provideAutoDisconnectThreadPool () {
    return Executors.newCachedThreadPool();
}

想在服务器停止时关闭threadPool，所以在我的restlet.Application中，我使用inject来获取实例：

@Override
public void stop() throws Exception {
    LOGGER.info("stopping...");
    // shutdown threadPool
    injector.getInstance(ExecutorService.class).shutdown();
    super.stop();
    LOGGER.info("stopped");
}

但是，该程序得到错误：

com.google.inject.ConfigurationException: Guice configuration errors:

1) No implementation for java.util.concurrent.ExecutorService was bound.
 while locating java.util.concurrent.ExecutorService

1 error
at    com.google.inject.internal.InjectorImpl.getProvider(InjectorImpl.java:1004)
at com.google.inject.internal.InjectorImpl.getInstance(InjectorImpl.java:1009)

那么，如何在应用程序停止时获取threadPool实例。

Answer 1

Named是绑定注释 ，因此在这种情况下注入键是ExecutorService.class 和 @Named("name0") ：

injector.getInstance(Key.get(ExecutorService.class, Names.named("name0")))