From a21a0549cdeb9f31db42c7273067aa85c76f6330 Mon Sep 17 00:00:00 2001
From: Christoph Stahl <christoph.stahl@tu-dortmund.de>
Date: Sun, 5 May 2024 13:20:20 +0200
Subject: [PATCH] Blatt 02

---
 src/main/java/com/example/AkkaMainSystem.java | 13 ++++-
 src/main/java/com/example/ExampleActor.java   | 35 ------------
 .../java/com/example/ExampleTimerActor.java   | 45 ---------------
 src/main/java/com/example/RelayBot.java       | 55 +++++++++++++++++++
 4 files changed, 65 insertions(+), 83 deletions(-)
 delete mode 100644 src/main/java/com/example/ExampleActor.java
 delete mode 100644 src/main/java/com/example/ExampleTimerActor.java
 create mode 100644 src/main/java/com/example/RelayBot.java

diff --git a/src/main/java/com/example/AkkaMainSystem.java b/src/main/java/com/example/AkkaMainSystem.java
index 868351b..a77fcda 100644
--- a/src/main/java/com/example/AkkaMainSystem.java
+++ b/src/main/java/com/example/AkkaMainSystem.java
@@ -4,6 +4,9 @@ import akka.actor.typed.ActorRef;
 import akka.actor.typed.Behavior;
 import akka.actor.typed.javadsl.*;
 
+import java.util.ArrayList;
+import java.util.Arrays;
+
 public class AkkaMainSystem extends AbstractBehavior<AkkaMainSystem.Create> {
 
     public static class Create {
@@ -24,11 +27,15 @@ 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<ExampleTimerActor.Message> b = this.getContext().spawn(ExampleTimerActor.create(), "timeractor");
+        var alice = this.getContext().spawn(RelayBot.create("alice"), "alice");
+        var bob = this.getContext().spawn(RelayBot.create("bob"), "bob");
+        var charlie = this.getContext().spawn(RelayBot.create("charlie"), "charlie");
+
+        var reihenfolge = new ArrayList<>(Arrays.asList(bob, charlie, alice));
+        alice.tell(new RelayBot.Start(reihenfolge));
+
         //#create-actors
 
-        a.tell(new ExampleActor.ExampleMessage(this.getContext().getSelf(),"Test123"));
         return this;
     }
 }
diff --git a/src/main/java/com/example/ExampleActor.java b/src/main/java/com/example/ExampleActor.java
deleted file mode 100644
index cf56713..0000000
--- a/src/main/java/com/example/ExampleActor.java
+++ /dev/null
@@ -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;
-    }
-}
diff --git a/src/main/java/com/example/ExampleTimerActor.java b/src/main/java/com/example/ExampleTimerActor.java
deleted file mode 100644
index 0bffbea..0000000
--- a/src/main/java/com/example/ExampleTimerActor.java
+++ /dev/null
@@ -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;
-    }
-}
diff --git a/src/main/java/com/example/RelayBot.java b/src/main/java/com/example/RelayBot.java
new file mode 100644
index 0000000..afac932
--- /dev/null
+++ b/src/main/java/com/example/RelayBot.java
@@ -0,0 +1,55 @@
+package com.example;
+
+import akka.actor.typed.ActorRef;
+import akka.actor.typed.Behavior;
+import akka.actor.typed.javadsl.*;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class RelayBot extends AbstractBehavior<RelayBot.Message> {
+
+    public interface Message {};
+
+    public record Hello(List<ActorRef<RelayBot.Message>> reihenfolge, int count) implements Message {  }
+    public record Start(List<ActorRef<Message>> reihenfolge) implements Message {  }
+
+    public static Behavior<Message> create(String name) {
+        return Behaviors.setup(context -> new RelayBot(context, name));
+    }
+
+    private final String name;
+
+    private RelayBot(ActorContext<Message> context, String name) {
+        super(context);
+        this.name = name;
+    }
+
+    @Override
+    public Receive<Message> createReceive() {
+        return newReceiveBuilder()
+                .onMessage(Hello.class, this::onHello)
+                .onMessage(Start.class, this::onStart)
+                .build();
+    }
+
+    private  Behavior<Message> onStart(Start msg) {
+        var next_hop = msg.reihenfolge.remove(0);
+        var new_reihenfolge = new ArrayList<>(msg.reihenfolge);
+        new_reihenfolge.add(next_hop);
+        next_hop.tell(new Hello(new_reihenfolge, 1));
+        return this;
+    }
+
+    private Behavior<Message> onHello(Hello msg) {
+        if (msg.count > 15) {
+            return Behaviors.stopped();
+        }
+        getContext().getLog().info("I, {}, got Hello ({})", this.name, msg.count);
+        var next_hop = msg.reihenfolge.remove(0);
+        var new_reihenfolge = new ArrayList<>(msg.reihenfolge);
+        new_reihenfolge.add(next_hop);
+        next_hop.tell(new Hello(new_reihenfolge, msg.count + 1));
+        return this;
+    }
+}