在服务器启动时使用 Akka 播放框架调度程序

Question

问题 1： 我使用 play 2.1.1 创建了一个示例 java 应用程序，并在应用程序启动时启动了调度程序。我做了一个播放编译然后播放开始，但我收到以下错误，如果我在这里做错了什么，请告诉我：

(Starting server. Type Ctrl+D to exit logs, the server will remain in background)

Play server process ID is 6160
@6edl861on: Cannot init the Global objectOops, cannot start the server.

    at play.api.WithDefaultGlobal$$anonfun$play$api$WithDefaultGlobal$$globalInstance$1.apply(Application.scala:57)
    at play.api.WithDefaultGlobal$$anonfun$play$api$WithDefaultGlobal$$globalInstance$1.apply(Application.scala:51)
    at play.utils.Threads$.withContextClassLoader(Threads.scala:18)
    at play.api.WithDefaultGlobal$class.play$api$WithDefaultGlobal$$globalInstance(Application.scala:50)
    at play.api.DefaultApplication.play$api$WithDefaultGlobal$$globalInstance$lzycompute(Application.scala:383)
    at play.api.DefaultApplication.play$api$WithDefaultGlobal$$globalInstance(Application.scala:383)
    at play.api.WithDefaultGlobal$class.global(Application.scala:66)
    at play.api.DefaultApplication.global(Application.scala:383)
    at play.api.WithDefaultConfiguration$class.play$api$WithDefaultConfiguration$$fullConfiguration(Application.scala:80)
    at play.api.DefaultApplication.play$api$WithDefaultConfiguration$$fullConfiguration$lzycompute(Application.scala:383)
    at play.api.DefaultApplication.play$api$WithDefaultConfiguration$$fullConfiguration(Application.scala:383)
    at play.api.WithDefaultConfiguration$class.configuration(Application.scala:82)
    at play.api.DefaultApplication.configuration(Application.scala:383)
    at play.api.Application$class.$init$(Application.scala:268)
    at play.api.DefaultApplication.<init>(Application.scala:383)
    at play.core.StaticApplication.<init>(ApplicationProvider.scala:52)
    at play.core.server.NettyServer$.createServer(NettyServer.scala:228)
    at play.core.server.NettyServer$$anonfun$main$5.apply(NettyServer.scala:259)
    at play.core.server.NettyServer$$anonfun$main$5.apply(NettyServer.scala:258)
    at scala.Option.map(Option.scala:145)
    at play.core.server.NettyServer$.main(NettyServer.scala:258)
    at play.core.server.NettyServer.main(NettyServer.scala)
Caused by: java.lang.RuntimeException: There is no started application
    at scala.sys.package$.error(package.scala:27)
    at play.api.Play$$anonfun$current$1.apply(Play.scala:46)
    at play.api.Play$$anonfun$current$1.apply(Play.scala:46)
    at scala.Option.getOrElse(Option.scala:120)
    at play.api.Play$.current(Play.scala:46)
    at play.api.Play.current(Play.scala)
    at play.libs.Akka.system(Akka.java:25)
    at Global.<init>(Global.java:27)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at java.lang.Class.newInstance0(Unknown Source)
    at java.lang.Class.newInstance(Unknown Source)
    at play.api.WithDefaultGlobal$class.play$api$WithDefaultGlobal$$javaGlobal(Application.scala:30)
    at play.api.DefaultApplication.play$api$WithDefaultGlobal$$javaGlobal$lzycompute(Application.scala:383)
    at play.api.DefaultApplication.play$api$WithDefaultGlobal$$javaGlobal(Application.scala:383)
    at play.api.WithDefaultGlobal$$anonfun$play$api$WithDefaultGlobal$$globalInstance$1.apply(Application.scala:52)

资源：

Global.java - 在应用程序中/

public class Global extends GlobalSettings {

private Logger.ALogger log = Logger.of(Global.class);

private ActorRef myActor = Akka.system().actorOf(
        new Props(Retreiver.class));

@Override
public void onStart(Application app) {
    log.info(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>");
    Akka.system()
            .scheduler()
            .schedule(Duration.create(0, TimeUnit.MILLISECONDS),
                    Duration.create(10, TimeUnit.SECONDS), myActor, "tick",
                    Akka.system().dispatcher());

}
}

Retreiver.java：

public class Retreiver extends UntypedActor {

private Logger.ALogger log = Logger.of(TweetsRetreiver.class);

@Override
public void onReceive(Object arg0) throws Exception {

    // some code here    

}

}

application.conf：

application.global=Global

问题 2：另外，在控制台或 Application.log 文件中都没有打印任何日志。我使用 play.Logger 包进行日志记录，这是用于登录 play 2.1.1 的正确包吗？请为此提供一个示例。

谢谢。

Answer 1

解决了。线路问题：

private ActorRef myActor = Akka.system().actorOf(
    new Props(Retreiver.class));

当我在 onStart 方法中移动它时，它被正确触发了。不知道为什么我不能在课堂上定义这个。需要检查。

Answer 2

对于日志记录问题，您必须使用Play's Logger helper：

@Override
public void onStart(Application app) {
    play.Logger.info(">>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>");
    ...
}