Akka Getting Started-simple example

The following procedure demonstrates a simple example of Akka. Create an actor to process a command that interacts with the message delivery.

I use the Akka version and the associated jar package see the Pom file:

<project xmlns= "http://maven.apache.org/POM/4.0.0" xmlns:xsi= "Http://www.w3.org/2001/XMLSchema-instance" xsi: schemalocation= "http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd" > < Modelversion >4.0.0 </modelVersion> <groupid >com.focusedu.akka </groupId> <artifactid >ak 

  ka-first</artifactid> <version >0.0.1-snapshot </version> <packaging >jar </packaging> <name >akka-first</name> <url >http://maven.apache.org </url> <properties > &L t;project.build.sourceencoding> utf-8</project.build.sourceencoding> </properties > < Dependencies > <dependency > <groupid >junit</groupId> <artifactid >junit</a rtifactid> <version >3.8.1 </version> <scope >test </scope> </dependency
    ; <dependency > <groupId> Com.typesaFe.akka</groupid > <artifactId> akka-actor_2.10 </artifactId> <version> 2.3.10&L
           t;/version> </dependency > <dependency > <groupId> log4j</groupid>  <artifactId> log4j</artifactid> <version> 1.2.17</version> </dependency > <dependency > <groupId> com.google.guava</groupid > <artifactId> Guava</artifactid > <version> 18.0</version> </dependency > <dependency &
        Gt <groupId> ch.qos.logback</groupid > <artifactId> logback-classic </artifactId> &lt ;version> 1.1.1</version> </dependency > <dependency > <groupId> com.typesafe. Akka</groupid > <artifactId> akka-persistence-experimental_2.10 </artifactId> <versio N> 2.3.10</version> </dependency > </dependencies > </project>
  

1. Creating Event Events

Import java.io.Serializable;

public class Event implements Serializable {

  private String data;
  Private String uuid;


  Public Event (String data) {
    super ();
    This. data = data;
  }

  Public Event (string data, string uuid) {this
    . data = data;
    This. UUID = UUID;
  }

  Public String GetData () {
    return data;
  }

  Public String Getuuid () {
    return uuid;
  }

  @Override public
  String toString () {
    return "event{" + "Data= '" + data + ' \ ' + ", uuid= ' + uuid + ' \ ' + '} ';
  }
}

2. Create a Command object
The main method is to override the OnReceive method, which is used to process the received message.

Import java.io.Serializable;

public class Command implements Serializable {
     private static final long serialversionuid = 1L;
     Private final String data;

     Public Command (String data) {
           this.data = data;
     }

     Public String GetData () {
           return this. data;
     }

     @Override public
     String toString () {
           return "command{" + "Data= '" + data + ' \ ' + '} ';}
     }

3. Create an Actor object

Import Java.util.UUID;

Import Com.center.akka.simple.command.Command;
Import com.center.akka.simple.event.Event;

Import Akka.actor.UntypedActor;
Import akka.event.Logging;
Import Akka.event.LoggingAdapter;

public class Simpleactor extends Untypedactor {

     Loggingadapter log = Logging.getlogger (GetContext (). System (), this) ;

     Public Simpleactor () {
           log.info ("Simpleactor constructor");
     }

     @Override public
     void OnReceive (Object msg) throws Exception {

           log.info ("Received Command:" + msg);
           if (msg instanceof Command) {
               final String data = (Command) msg). GetData ();
               Final Event Event = new event (data, Uuid.randomuuid (). toString ());
               Emmit an event somewhere ...

          } else if (msg. Equals ("echo")) {
               log.info ("echo!");}}
}

4. Test class

Import Org.slf4j.Logger;

Import Org.slf4j.LoggerFactory;
Import Akka.actor.ActorRef;
Import Akka.actor.ActorSystem;

Import Akka.actor.Props;
Import Com.center.akka.simple.actor.SimpleActor;

Import Com.center.akka.simple.command.Command; /** * * @author LCQ * * */public class System {public static final Logger log = Loggerfactory.getlogger (System.clas

  s); public static void Main (String ... args) throws Exception {final Actorsystem Actorsystem = actorsystem.create ("actor-

    System ");

    Thread.Sleep (5000);

    Final Actorref actorref = Actorsystem.actorof (Props.create (Simpleactor. Class), "Simple-actor");
    Actorref.tell (New Command ("CMD 1"), null);
    Actorref.tell (New Command ("CMD 2"), NULL);
    Actorref.tell (New Command ("CMD 3"), NULL);
    Actorref.tell (New Command ("CMD 4"), NULL);

    Actorref.tell (New Command ("CMD 5"), NULL);

    Thread.Sleep (5000);

    Log.debug ("Actor System Shutdown starting ...");
  Actorsystem.shutdown ();
 }
}

The two concepts that need to be differentiated are:
Actorref.tell: Asynchronously sends a message and returns immediately;
Actorref.ask: Asynchronously sends a message and returns a future that represents a possible response;
So always use tell to be more performance, unless you have to use ask


Operation Result:

[INFO] [05/17/2015 17:46:44.224] [Actor-system-akka.actor.default-dispatcher-3] [Akka://actor-system/user/simple-actor] SimpleActor constructor [ INFO] [05/17/2015 17:46:44.225] [actor-system-akka.actor.default-dispatcher-3] [akka://actor-system/user/ Simple-actor] Received command:command{data= ' CMD 1 '} [INFO] [05/17/2015 17:46:44.312] [ ACTOR-SYSTEM-AKKA.ACTOR.DEFAULT-DISPATCHER-3] [Akka://actor-system/user/simple-actor] Received command:command{ Data= ' CMD 2 '} [INFO] [05/17/2015 17:46:44.312] [actor-system-akka.actor.default-dispatcher-3] [akka://actor-system/ User/simple-actor] Received command:command{data= ' CMD 3 '} [INFO] [05/17/2015 17:46:44.312] [ ACTOR-SYSTEM-AKKA.ACTOR.DEFAULT-DISPATCHER-3] [Akka://actor-system/user/simple-actor] Received command:command{ Data= ' CMD 4 '} [INFO] [05/17/2015 17:46:44.312] [actor-system-akka.actor.default-dispatcher-3] [akka://actor-system/ User/simple-actor] Received command:command{data= ' CMD 5 '} 17:46:49.226 [main] DEBUG Com.center.akka.simple.app.SysTem-actor System Shutdown Starting ...