akka学习教程(七) 内置状态转换Procedure

时间：2023-01-01 22:06:02

akka系列文章目录

在actor运行过程中，可能会有多种状态，各个状态间可能会存在切换的情况，akka已经帮我们考虑到这种情况情况的处理:Procedure.
下面模拟一个婴儿。婴儿有两种不同的状态，开心和生气，婴儿有个特点就是好玩，永远不会累，所以让其睡觉婴儿就会生气，让他继续玩就会很高兴。
简单代码如下：

package akka;

import akka.actor.*;
import akka.event.Logging;
import akka.event.LoggingAdapter;
import akka.japi.Procedure;
import com.typesafe.config.ConfigFactory;

/**
 * Created by liubenlong on 2017/1/12.
 */
public class ProcedureTest extends UntypedActor {

private final LoggingAdapter log = Logging.getLogger(getContext().system(), this);

    Procedure<Object> happy = new Procedure<Object>() {
@Override
public void apply(Object o) throws Exception {
            log.info("i am happy! " + o);
if (o == Msg.PLAY) {
                getSender().tell("i am alrady happy!!", getSelf());
                log.info("i am alrady happy!!");
            } else if (o == Msg.SLEEP) {
                log.info("i do not like sleep!");
                getContext().become(angray);
            } else {
                unhandled(o);
            }
        }
    };

    Procedure<Object> angray = new Procedure<Object>() {
@Override
public void apply(Object o) throws Exception {
            log.info("i am angray! "+o);
if(o ==Msg.SLEEP){
                getSender().tell("i am alrady angray!!", getSelf());
                log.info("i am alrady angray!!");
            } else if(o ==Msg.PLAY) {
                log.info("i like play.");
                getContext().become(happy);
            } else {
                unhandled(o);
            }
        }
    };


@Override
public void onReceive(Object o) throws Throwable {
        log.info("onReceive msg: " + o);
if(o == Msg.SLEEP){
            getContext().become(angray);
        }else if(o == Msg.PLAY){
            getContext().become(happy);
        }else {
            unhandled(o);
        }

    }



public static void main(String[] args) throws InterruptedException {
        ActorSystem system = ActorSystem.create("strategy", ConfigFactory.load("akka.config"));
        ActorRef procedureTest = system.actorOf(Props.create(ProcedureTest.class), "ProcedureTest");

        procedureTest.tell(Msg.PLAY, ActorRef.noSender());
        procedureTest.tell(Msg.SLEEP, ActorRef.noSender());
        procedureTest.tell(Msg.PLAY, ActorRef.noSender());
        procedureTest.tell(Msg.PLAY, ActorRef.noSender());

        procedureTest.tell(PoisonPill.getInstance(), ActorRef.noSender());
    }
}

输出结果：

[INFO] [01/16/2017 15:50:53.967] [strategy-akka.actor.default-dispatcher-2] [akka://strategy/user/ProcedureTest] onReceive msg: PLAY
[INFO] [01/16/2017 15:50:54.000] [strategy-akka.actor.default-dispatcher-2] [akka://strategy/user/ProcedureTest] i am happy! SLEEP
[INFO] [01/16/2017 15:50:54.000] [strategy-akka.actor.default-dispatcher-2] [akka://strategy/user/ProcedureTest] i do not like sleep!
[INFO] [01/16/2017 15:50:54.000] [strategy-akka.actor.default-dispatcher-2] [akka://strategy/user/ProcedureTest] i am angray! PLAY
[INFO] [01/16/2017 15:50:54.000] [strategy-akka.actor.default-dispatcher-2] [akka://strategy/user/ProcedureTest] i like play.
[INFO] [01/16/2017 15:50:54.000] [strategy-akka.actor.default-dispatcher-2] [akka://strategy/user/ProcedureTest] i am happy! PLAY
[INFO] [01/16/2017 15:50:54.004] [strategy-akka.actor.default-dispatcher-2] [akka://strategy/user/ProcedureTest] i am alrady happy!!

注意：

  • akka.ProcedureTest#onReceive这个方法只被调用一次，只有的切换均在procedure中处理，所以在实际开发过程中要注意状态切换的准确性。

参考资料
标签：

相关文章