Blatt 5

src/main/java/com/example/AkkaMainSystem.java

@@ -24,11 +24,13 @@ public class AkkaMainSystem extends AbstractBehavior<AkkaMainSystem.Create> {
 
     private Behavior<Create> onCreate(Create command) {
         //#create-actors
-        ActorRef<ExampleActor.Message> a = this.getContext().spawn(ExampleActor.create("Alice"), "alice");
+        ActorRef<Queue.Message> queue = this.getContext().spawn(Queue.create(), "queue");
-        ActorRef<ExampleTimerActor.Message> b = this.getContext().spawn(ExampleTimerActor.create(), "timeractor");
+        ActorRef<Producer.Message> producer = this.getContext().spawn(Producer.create(queue), "producer");
+        ActorRef<ConsumerFactory.Message> cFactory = this.getContext().spawn(ConsumerFactory.create(queue), "cFactory");
         //#create-actors
 
-        a.tell(new ExampleActor.ExampleMessage(this.getContext().getSelf(),"Test123"));
+        producer.tell(new Producer.Start(90));
+        cFactory.tell(new ConsumerFactory.Start(100));
         return this;
     }
 }

src/main/java/com/example/Consumer.java

@@ -0,0 +1,46 @@
+package com.example;
+
+import akka.actor.typed.ActorRef;
+import akka.actor.typed.Behavior;
+import akka.actor.typed.javadsl.AbstractBehavior;
+import akka.actor.typed.javadsl.ActorContext;
+import akka.actor.typed.javadsl.Behaviors;
+import akka.actor.typed.javadsl.Receive;
+
+public class Consumer extends AbstractBehavior<Consumer.Message> {
+
+    public interface Message {};
+
+    public record Reply(int i) implements Message {  }
+    public enum Error implements Message {
+        EMPTY_QUEUE
+    }
+
+    public static Behavior<Message> create(ActorRef<Queue.Message> queue) {
+        return Behaviors.setup(context -> new Consumer(context, queue));
+    }
+
+    private final ActorRef<Queue.Message> queue;
+
+    private Consumer(ActorContext<Message> context, ActorRef<Queue.Message> queue) {
+        super(context);
+        this.queue = queue;
+        this.queue.tell(new Queue.Get(this.getContext().getSelf()));
+    }
+
+    @Override
+    public Receive<Message> createReceive() {
+        return newReceiveBuilder()
+                .onMessage(Reply.class, this::onReply)
+                .onMessage(Error.class, this::onError)
+                .build();
+    }
+    private Behavior<Message> onError(Error msg) {
+        this.getContext().getLog().info("ERROR: {}", msg.toString());
+        return this;
+    }
+    private Behavior<Message> onReply(Reply msg) {
+        this.getContext().getLog().info("Got: {}", msg.i);
+        return this;
+    }
+}

src/main/java/com/example/ConsumerFactory.java

@@ -0,0 +1,40 @@
+package com.example;
+
+import akka.actor.typed.ActorRef;
+import akka.actor.typed.Behavior;
+import akka.actor.typed.javadsl.AbstractBehavior;
+import akka.actor.typed.javadsl.ActorContext;
+import akka.actor.typed.javadsl.Behaviors;
+import akka.actor.typed.javadsl.Receive;
+
+public class ConsumerFactory extends AbstractBehavior<ConsumerFactory.Message> {
+
+    public interface Message {};
+
+    public record Start(int amount) implements Message {  }
+
+    public static Behavior<Message> create(ActorRef<Queue.Message> queue) {
+        return Behaviors.setup(context -> new ConsumerFactory(context, queue));
+    }
+
+    private final ActorRef<Queue.Message> queue;
+
+    private ConsumerFactory(ActorContext<Message> context, ActorRef<Queue.Message> queue) {
+        super(context);
+        this.queue = queue;
+    }
+
+    @Override
+    public Receive<Message> createReceive() {
+        return newReceiveBuilder()
+                .onMessage(Start.class, this::onStart)
+                .build();
+    }
+
+    private Behavior<Message> onStart(Start msg) {
+        for(int i=0; i < msg.amount; i++) {
+            this.getContext().spawnAnonymous(Consumer.create(this.queue));
+        }
+        return this;
+    }
+}

src/main/java/com/example/ExampleActor.java

@@ -1,35 +0,0 @@
-package com.example;
-
-import akka.actor.typed.ActorRef;
-import akka.actor.typed.Behavior;
-import akka.actor.typed.javadsl.*;
-
-public class ExampleActor extends AbstractBehavior<ExampleActor.Message> {
-
-    public interface Message {};
-
-    public record ExampleMessage(ActorRef<AkkaMainSystem.Create> someReference, String someString) implements Message {  }
-
-    public static Behavior<Message> create(String name) {
-        return Behaviors.setup(context -> new ExampleActor(context, name));
-    }
-
-    private final String name;
-
-    private ExampleActor(ActorContext<Message> context, String name) {
-        super(context);
-        this.name = name;
-    }
-
-    @Override
-    public Receive<Message> createReceive() {
-        return newReceiveBuilder()
-                .onMessage(ExampleMessage.class, this::onExampleMessage)
-                .build();
-    }
-
-    private Behavior<Message> onExampleMessage(ExampleMessage msg) {
-        getContext().getLog().info("I ({}) got a message: ExampleMessage({},{})", this.name, msg.someReference, msg.someString);
-        return this;
-    }
-}

src/main/java/com/example/ExampleTimerActor.java

@@ -1,45 +0,0 @@
-package com.example;
-
-import akka.actor.typed.javadsl.TimerScheduler;
-import akka.actor.typed.Behavior;
-import akka.actor.typed.javadsl.AbstractBehavior;
-import akka.actor.typed.javadsl.ActorContext;
-import akka.actor.typed.javadsl.Behaviors;
-import akka.actor.typed.javadsl.Receive;
-
-import java.time.Duration;
-
-
-public class ExampleTimerActor extends AbstractBehavior<ExampleTimerActor.Message> {
-
-    public interface Message {};
-
-
-    public record ExampleMessage(String someString) implements Message {  }
-
-    public static Behavior<Message> create() {
-        return Behaviors.setup(context -> Behaviors.withTimers(timers -> new ExampleTimerActor(context, timers)));
-    }
-
-    private final TimerScheduler<ExampleTimerActor.Message> timers;
-
-    private ExampleTimerActor(ActorContext<Message> context, TimerScheduler<ExampleTimerActor.Message> timers) {
-        super(context);
-        this.timers = timers;
-
-        Message msg = new ExampleMessage("test123");
-        this.timers.startSingleTimer(msg, msg, Duration.ofSeconds(10));
-    }
-
-    @Override
-    public Receive<Message> createReceive() {
-        return newReceiveBuilder()
-                .onMessage(ExampleMessage.class, this::onExampleMessage)
-                .build();
-    }
-
-    private Behavior<Message> onExampleMessage(ExampleMessage msg) {
-        getContext().getLog().info("I have send myself this message after 10 Seconds: {}", msg.someString);
-        return this;
-    }
-}

src/main/java/com/example/Producer.java

@@ -0,0 +1,40 @@
+package com.example;
+
+import akka.actor.typed.ActorRef;
+import akka.actor.typed.Behavior;
+import akka.actor.typed.javadsl.AbstractBehavior;
+import akka.actor.typed.javadsl.ActorContext;
+import akka.actor.typed.javadsl.Behaviors;
+import akka.actor.typed.javadsl.Receive;
+
+public class Producer extends AbstractBehavior<Producer.Message> {
+
+    public interface Message {};
+
+    public record Start(int amount) implements Message {  }
+
+    public static Behavior<Message> create(ActorRef<Queue.Message> queue) {
+        return Behaviors.setup(context -> new Producer(context, queue));
+    }
+
+    private final ActorRef<Queue.Message> queue;
+
+    private Producer(ActorContext<Message> context, ActorRef<Queue.Message> queue) {
+        super(context);
+        this.queue = queue;
+    }
+
+    @Override
+    public Receive<Message> createReceive() {
+        return newReceiveBuilder()
+                .onMessage(Start.class, this::onStart)
+                .build();
+    }
+
+    private Behavior<Message> onStart(Start msg) {
+        for(int i = 0; i < msg.amount; i++) {
+            this.queue.tell(new Queue.Put(i));
+        }
+        return this;
+    }
+}

src/main/java/com/example/Queue.java

@@ -0,0 +1,51 @@
+package com.example;
+
+import akka.actor.typed.ActorRef;
+import akka.actor.typed.Behavior;
+import akka.actor.typed.javadsl.AbstractBehavior;
+import akka.actor.typed.javadsl.ActorContext;
+import akka.actor.typed.javadsl.Behaviors;
+import akka.actor.typed.javadsl.Receive;
+
+import java.util.ArrayList;
+
+public class Queue extends AbstractBehavior<Queue.Message> {
+
+    private final ArrayList<Integer> queue;
+
+    public interface Message {};
+
+    public record Get(ActorRef<Consumer.Message> replyTo) implements Message {  }
+    public record Put(int i) implements Message {  }
+
+    public static Behavior<Message> create() {
+        return Behaviors.setup(Queue::new);
+    }
+
+    private Queue(ActorContext<Message> context) {
+        super(context);
+        this.queue = new ArrayList<Integer>();
+    }
+
+    @Override
+    public Receive<Message> createReceive() {
+        return newReceiveBuilder()
+                .onMessage(Get.class, this::onGet)
+                .onMessage(Put.class, this::onPut)
+                .build();
+    }
+
+    private Behavior<Message> onPut(Put msg) {
+        this.queue.add(msg.i);
+        return this;
+    }
+    private Behavior<Message> onGet(Get msg) {
+        if (this.queue.isEmpty()) {
+            msg.replyTo.tell(Consumer.Error.EMPTY_QUEUE);
+        } else {
+            int i = this.queue.remove(0);
+            msg.replyTo.tell(new Consumer.Reply(i));
+        }
+        return this;
+    }
+}