Java 11501 (#12405)

* added parent module (akka-modules)

* moved akka-http(submodule) to akka-modules(parent)

* moved akka-streams(submodule) to akka-modules(parent)

* moved spring-akka(submodule) to akka-modules(parent)

* deleted submodules that we moved to akka-modules

Co-authored-by: panagiotiskakos <panagiotis.kakos@libra-is.com>

akka-modules/README.md

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+## Akka 
+
+This module contains modules about Akka. 

akka-modules/akka-http/README.md

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+## Akka HTTP
+
+This module contains articles about Akka HTTP. 
+
+### Relevant articles:
+
+- [Introduction to Akka HTTP](https://www.baeldung.com/akka-http)

akka-modules/akka-http/pom.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<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>
+    <artifactId>akka-http</artifactId>
+    <name>akka-http</name>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>akka-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>com.typesafe.akka</groupId>
+            <artifactId>akka-http_2.12</artifactId>
+            <version>${akka.http.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.typesafe.akka</groupId>
+            <artifactId>akka-stream_2.12</artifactId>
+            <version>${akka.stream.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.typesafe.akka</groupId>
+            <artifactId>akka-http-jackson_2.12</artifactId>
+            <version>${akka.http.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.typesafe.akka</groupId>
+            <artifactId>akka-http-testkit_2.12</artifactId>
+            <version>${akka.http.version}</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <properties>
+        <akka.http.version>10.0.11</akka.http.version>
+        <akka.stream.version>2.5.11</akka.stream.version>
+    </properties>
+
+</project>

akka-modules/akka-http/src/main/java/com/baeldung/akkahttp/User.java

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+package com.baeldung.akkahttp;
+
+public class User {
+
+    private final Long id;
+
+    private final String name;
+
+    public User() {
+        this.name = "";
+        this.id = null;
+    }
+
+    public User(Long id, String name) {
+        this.name = name;
+        this.id = id;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public Long getId() {
+        return id;
+    }
+}

akka-modules/akka-http/src/main/java/com/baeldung/akkahttp/UserActor.java

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+package com.baeldung.akkahttp;
+
+import akka.actor.AbstractActor;
+import akka.actor.Props;
+import akka.japi.pf.FI;
+import com.baeldung.akkahttp.UserMessages.ActionPerformed;
+import com.baeldung.akkahttp.UserMessages.CreateUserMessage;
+import com.baeldung.akkahttp.UserMessages.GetUserMessage;
+
+
+class UserActor extends AbstractActor {
+
+  private UserService userService = new UserService();
+
+  static Props props() {
+    return Props.create(UserActor.class);
+  }
+
+  @Override
+  public Receive createReceive() {
+    return receiveBuilder()
+            .match(CreateUserMessage.class, handleCreateUser())
+            .match(GetUserMessage.class, handleGetUser())
+            .build();
+  }
+
+  private FI.UnitApply<CreateUserMessage> handleCreateUser() {
+    return createUserMessageMessage -> {
+      userService.createUser(createUserMessageMessage.getUser());
+      sender().tell(new ActionPerformed(String.format("User %s created.", createUserMessageMessage.getUser()
+              .getName())), getSelf());
+    };
+  }
+
+  private FI.UnitApply<GetUserMessage> handleGetUser() {
+    return getUserMessageMessage -> {
+      sender().tell(userService.getUser(getUserMessageMessage.getUserId()), getSelf());
+    };
+  }
+
+}

akka-modules/akka-http/src/main/java/com/baeldung/akkahttp/UserMessages.java

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+package com.baeldung.akkahttp;
+
+import java.io.Serializable;
+
+public interface UserMessages {
+
+  class ActionPerformed implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+
+    private final String description;
+
+    public ActionPerformed(String description) {
+      this.description = description;
+    }
+
+    public String getDescription() {
+      return description;
+    }
+  }
+
+  class CreateUserMessage implements Serializable {
+
+    private static final long serialVersionUID = 1L;
+    private final User user;
+
+    public CreateUserMessage(User user) {
+      this.user = user;
+    }
+
+    public User getUser() {
+      return user;
+    }
+  }
+
+  class GetUserMessage implements Serializable {
+    private static final long serialVersionUID = 1L;
+    private final Long userId;
+
+    public GetUserMessage(Long userId) {
+      this.userId = userId;
+    }
+
+    public Long getUserId() {
+      return userId;
+    }
+  }
+
+}

akka-modules/akka-http/src/main/java/com/baeldung/akkahttp/UserServer.java

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+package com.baeldung.akkahttp;
+
+import java.util.Optional;
+import java.util.concurrent.CompletionStage;
+import java.util.concurrent.TimeUnit;
+
+import akka.actor.ActorRef;
+import akka.actor.ActorSystem;
+import akka.http.javadsl.marshallers.jackson.Jackson;
+import akka.http.javadsl.model.StatusCodes;
+import akka.http.javadsl.server.HttpApp;
+import akka.http.javadsl.server.Route;
+import akka.pattern.PatternsCS;
+import akka.util.Timeout;
+import com.baeldung.akkahttp.UserMessages.ActionPerformed;
+import com.baeldung.akkahttp.UserMessages.CreateUserMessage;
+import com.baeldung.akkahttp.UserMessages.GetUserMessage;
+import scala.concurrent.duration.Duration;
+import static akka.http.javadsl.server.PathMatchers.*;
+
+class UserServer extends HttpApp {
+
+  private final ActorRef userActor;
+
+  Timeout timeout = new Timeout(Duration.create(5, TimeUnit.SECONDS));
+
+  UserServer(ActorRef userActor) {
+    this.userActor = userActor;
+  }
+
+  @Override
+  public Route routes() {
+    return path("users", this::postUser)
+            .orElse(path(segment("users").slash(longSegment()), id ->
+                    route(getUser(id))));
+  }
+
+  private Route getUser(Long id) {
+    return get(() -> {
+      CompletionStage<Optional<User>> user = PatternsCS.ask(userActor, new GetUserMessage(id), timeout)
+              .thenApply(obj -> (Optional<User>) obj);
+
+      return onSuccess(() -> user, performed -> {
+        if (performed.isPresent())
+          return complete(StatusCodes.OK, performed.get(), Jackson.marshaller());
+        else
+          return complete(StatusCodes.NOT_FOUND);
+      });
+    });
+  }
+
+  private Route postUser() {
+    return route(post(() -> entity(Jackson.unmarshaller(User.class), user -> {
+      CompletionStage<ActionPerformed> userCreated = PatternsCS.ask(userActor, new CreateUserMessage(user), timeout)
+              .thenApply(obj -> (ActionPerformed) obj);
+
+      return onSuccess(() -> userCreated, performed -> {
+        return complete(StatusCodes.CREATED, performed, Jackson.marshaller());
+      });
+    })));
+  }
+
+  public static void main(String[] args) throws Exception {
+    ActorSystem system = ActorSystem.create("userServer");
+    ActorRef userActor = system.actorOf(UserActor.props(), "userActor");
+    UserServer server = new UserServer(userActor);
+    server.startServer("localhost", 8080, system);
+  }
+
+}

akka-modules/akka-http/src/main/java/com/baeldung/akkahttp/UserService.java

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+package com.baeldung.akkahttp;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Optional;
+
+public class UserService {
+
+  private final static List<User> users = new ArrayList<>();
+
+  static {
+    users.add(new User(1l, "Alice"));
+    users.add(new User(2l, "Bob"));
+    users.add(new User(3l, "Chris"));
+    users.add(new User(4l, "Dick"));
+    users.add(new User(5l, "Eve"));
+    users.add(new User(6l, "Finn"));
+  }
+
+  public Optional<User> getUser(Long id) {
+    return users.stream()
+            .filter(user -> user.getId()
+                    .equals(id))
+            .findFirst();
+  }
+
+  public void createUser(User user) {
+    users.add(user);
+  }
+
+  public List<User> getUsers(){
+    return users;
+  }
+
+}

akka-modules/akka-http/src/test/java/com/baeldung/akkahttp/UserServerUnitTest.java

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+package com.baeldung.akkahttp;
+
+import akka.actor.ActorRef;
+import akka.actor.ActorSystem;
+import akka.http.javadsl.model.ContentTypes;
+import akka.http.javadsl.model.HttpEntities;
+import akka.http.javadsl.model.HttpRequest;
+import akka.http.javadsl.testkit.JUnitRouteTest;
+import akka.http.javadsl.testkit.TestRoute;
+
+import org.junit.Ignore;
+import org.junit.Test;
+
+public class UserServerUnitTest extends JUnitRouteTest {
+
+  ActorSystem system = ActorSystem.create("helloAkkaHttpServer");
+
+  ActorRef userActorRef = system.actorOf(UserActor.props(), "userActor");
+
+  TestRoute appRoute = testRoute(new UserServer(userActorRef).routes());
+
+  @Ignore
+  @Test
+  public void whenRequest_thenActorResponds() {
+
+    appRoute.run(HttpRequest.GET("/users/1"))
+            .assertEntity(alice())
+            .assertStatusCode(200);
+
+    appRoute.run(HttpRequest.GET("/users/42"))
+            .assertStatusCode(404);
+
+    appRoute.run(HttpRequest.DELETE("/users/1"))
+            .assertStatusCode(405);
+
+    appRoute.run(HttpRequest.DELETE("/users/42"))
+            .assertStatusCode(405);
+
+    appRoute.run(HttpRequest.POST("/users")
+            .withEntity(HttpEntities.create(ContentTypes.APPLICATION_JSON, zaphod())))
+            .assertStatusCode(201);
+
+  }
+
+  private String alice() {
+    return "{\"id\":1,\"name\":\"Alice\"}";
+  }
+
+  private String zaphod() {
+    return "{\"id\":42,\"name\":\"Zaphod\"}";
+  }
+
+}

akka-modules/akka-streams/README.md

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+## Akka Streams
+
+This module contains articles about Akka Streams. 
+
+### Relevant articles
+
+- [Guide to Akka Streams](https://www.baeldung.com/akka-streams)

akka-modules/akka-streams/pom.xml

@@ -0,0 +1,33 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<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>
+    <artifactId>akka-streams</artifactId>
+    <name>akka-streams</name>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>akka-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>com.typesafe.akka</groupId>
+            <artifactId>akka-stream_${scala.version}</artifactId>
+            <version>${akkastreams.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>com.typesafe.akka</groupId>
+            <artifactId>akka-stream-testkit_${scala.version}</artifactId>
+            <version>${akkastreams.version}</version>
+        </dependency>
+    </dependencies>
+
+    <properties>
+        <akkastreams.version>2.5.2</akkastreams.version>
+        <scala.version>2.11</scala.version>
+    </properties>
+
+</project>

akka-modules/akka-streams/src/main/java/com/baeldung/akkastreams/AverageRepository.java

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+package com.baeldung.akkastreams;
+
+
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionStage;
+
+public class AverageRepository {
+    CompletionStage<Double> save(Double average) {
+        return CompletableFuture.supplyAsync(() -> {
+            System.out.println("saving average: " + average);
+            return average;
+        });
+    }
+}

akka-modules/akka-streams/src/main/java/com/baeldung/akkastreams/DataImporter.java

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+package com.baeldung.akkastreams;
+
+
+import akka.Done;
+import akka.NotUsed;
+import akka.actor.ActorSystem;
+import akka.stream.ActorMaterializer;
+import akka.stream.javadsl.Flow;
+import akka.stream.javadsl.Keep;
+import akka.stream.javadsl.Sink;
+import akka.stream.javadsl.Source;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionStage;
+import java.util.stream.Collectors;
+
+public class DataImporter {
+    private final ActorSystem actorSystem;
+    private final AverageRepository averageRepository = new AverageRepository();
+
+    public DataImporter(ActorSystem actorSystem) {
+        this.actorSystem = actorSystem;
+
+    }
+
+    private List<Integer> parseLine(String line) {
+        String[] fields = line.split(";");
+        return Arrays.stream(fields)
+                .map(Integer::parseInt)
+                .collect(Collectors.toList());
+    }
+
+    private Flow<String, Integer, NotUsed> parseContent() {
+        return Flow.of(String.class).mapConcat(this::parseLine);
+    }
+
+    private Flow<Integer, Double, NotUsed> computeAverage() {
+        return Flow.of(Integer.class).grouped(2).mapAsyncUnordered(8, integers ->
+                CompletableFuture.supplyAsync(() -> integers
+                        .stream()
+                        .mapToDouble(v -> v)
+                        .average()
+                        .orElse(-1.0)));
+    }
+
+    Flow<String, Double, NotUsed> calculateAverage() {
+        return Flow.of(String.class)
+                .via(parseContent())
+                .via(computeAverage());
+    }
+
+    private Sink<Double, CompletionStage<Done>> storeAverages() {
+        return Flow.of(Double.class)
+                .mapAsyncUnordered(4, averageRepository::save)
+                .toMat(Sink.ignore(), Keep.right());
+    }
+
+
+    CompletionStage<Done> calculateAverageForContent(String content) {
+        return Source.single(content)
+                .via(calculateAverage())
+                .runWith(storeAverages(), ActorMaterializer.create(actorSystem))
+                .whenComplete((d, e) -> {
+                    if (d != null) {
+                        System.out.println("Import finished ");
+                    } else {
+                        e.printStackTrace();
+                    }
+                });
+    }
+
+}

akka-modules/akka-streams/src/main/resources/logback.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n
+            </pattern>
+        </encoder>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT" />
+    </root>
+</configuration>

akka-modules/akka-streams/src/test/java/com/baeldung/akkastreams/DataImporterUnitTest.java

@@ -0,0 +1,43 @@
+package com.baeldung.akkastreams;
+
+import akka.NotUsed;
+import akka.actor.ActorSystem;
+import akka.stream.ActorMaterializer;
+import akka.stream.javadsl.Flow;
+import akka.stream.javadsl.Source;
+import akka.stream.testkit.javadsl.TestSink;
+import org.junit.Test;
+
+
+public class DataImporterUnitTest {
+    private final ActorSystem actorSystem = ActorSystem.create();
+
+    @Test
+    public void givenStreamOfIntegers_whenCalculateAverageOfPairs_thenShouldReturnProperResults() {
+        //given
+        Flow<String, Double, NotUsed> tested = new DataImporter(actorSystem).calculateAverage();
+        String input = "1;9;11;0";
+
+        //when
+        Source<Double, NotUsed> flow = Source.single(input).via(tested);
+
+        //then
+        flow
+                .runWith(TestSink.probe(actorSystem), ActorMaterializer.create(actorSystem))
+                .request(4)
+                .expectNextUnordered(5d, 5.5);
+    }
+
+    @Test
+    public void givenStreamOfIntegers_whenCalculateAverageAndSaveToSink_thenShouldFinishSuccessfully() {
+        //given
+        DataImporter dataImporter = new DataImporter(actorSystem);
+        String input = "10;90;110;10";
+
+        //when
+        dataImporter.calculateAverageForContent(input)
+                .thenAccept(d -> actorSystem.terminate());
+
+    }
+
+}

akka-modules/pom.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<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>
+    <artifactId>akka-modules</artifactId>
+    <version>1.0.0-SNAPSHOT</version>
+    <name>akka-modules</name>
+    <packaging>pom</packaging>
+
+    <parent>
+        <artifactId>parent-modules</artifactId>
+        <groupId>com.baeldung</groupId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <modules>
+        <module>akka-http</module>
+        <module>akka-streams</module>
+        <module>spring-akka</module>
+    </modules>
+
+    <build>
+        <pluginManagement>
+            <plugins>
+                <plugin>
+                    <groupId>org.springframework.boot</groupId>
+                    <artifactId>spring-boot-maven-plugin</artifactId>
+                </plugin>
+            </plugins>
+        </pluginManagement>
+    </build>
+
+</project>

akka-modules/spring-akka/README.md

@@ -0,0 +1,6 @@
+## Spring Akka
+
+This module contains articles about Spring with Akka
+
+### Relevant Articles:
+- [Introduction to Spring with Akka](https://www.baeldung.com/akka-with-spring)

akka-modules/spring-akka/pom.xml

@@ -0,0 +1,51 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+    xmlns="http://maven.apache.org/POM/4.0.0"
+    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>
+    <artifactId>spring-akka</artifactId>
+    <version>0.1-SNAPSHOT</version>
+    <name>spring-akka</name>
+
+    <parent>
+        <groupId>com.baeldung</groupId>
+        <artifactId>akka-modules</artifactId>
+        <version>1.0.0-SNAPSHOT</version>
+    </parent>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-context</artifactId>
+        </dependency>
+        <dependency>
+            <groupId>com.typesafe.akka</groupId>
+            <artifactId>akka-actor_${scala.version}</artifactId>
+            <version>${akka.version}</version>
+        </dependency>
+        <dependency>
+            <groupId>org.springframework</groupId>
+            <artifactId>spring-test</artifactId>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <dependencyManagement>
+        <dependencies>
+            <dependency>
+                <groupId>org.springframework</groupId>
+                <artifactId>spring-framework-bom</artifactId>
+                <version>${spring.version}</version>
+                <type>pom</type>
+                <scope>import</scope>
+            </dependency>
+        </dependencies>
+    </dependencyManagement>
+
+    <properties>
+        <spring.version>4.3.4.RELEASE</spring.version>
+        <akka.version>2.4.14</akka.version>
+        <scala.version>2.11</scala.version>
+    </properties>
+
+</project>

akka-modules/spring-akka/src/main/java/com/baeldung/akka/AppConfiguration.java

@@ -0,0 +1,24 @@
+package com.baeldung.akka;
+
+import akka.actor.ActorSystem;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.ApplicationContext;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Configuration;
+
+@Configuration
+@ComponentScan
+public class AppConfiguration {
+
+    @Autowired
+    private ApplicationContext applicationContext;
+
+    @Bean
+    public ActorSystem actorSystem() {
+        ActorSystem system = ActorSystem.create("akka-spring-demo");
+        SpringExtension.SPRING_EXTENSION_PROVIDER.get(system).initialize(applicationContext);
+        return system;
+    }
+
+}

akka-modules/spring-akka/src/main/java/com/baeldung/akka/GreetingActor.java

@@ -0,0 +1,42 @@
+package com.baeldung.akka;
+
+import akka.actor.UntypedActor;
+import org.springframework.beans.factory.config.ConfigurableBeanFactory;
+import org.springframework.context.annotation.Scope;
+import org.springframework.stereotype.Component;
+
+@Component
+@Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
+public class GreetingActor extends UntypedActor {
+
+    private GreetingService greetingService;
+
+    public GreetingActor(GreetingService greetingService) {
+        this.greetingService = greetingService;
+    }
+
+    @Override
+    public void onReceive(Object message) throws Throwable {
+        if (message instanceof Greet) {
+            String name = ((Greet) message).getName();
+            getSender().tell(greetingService.greet(name), getSelf());
+        } else {
+            unhandled(message);
+        }
+    }
+
+    public static class Greet {
+
+        private String name;
+
+        public Greet(String name) {
+            this.name = name;
+        }
+
+        public String getName() {
+            return name;
+        }
+
+    }
+
+}

akka-modules/spring-akka/src/main/java/com/baeldung/akka/GreetingService.java

@@ -0,0 +1,12 @@
+package com.baeldung.akka;
+
+import org.springframework.stereotype.Component;
+
+@Component
+public class GreetingService {
+
+    public String greet(String name) {
+        return "Hello, " + name;
+    }
+
+}

akka-modules/spring-akka/src/main/java/com/baeldung/akka/SpringActorProducer.java

@@ -0,0 +1,28 @@
+package com.baeldung.akka;
+
+import akka.actor.Actor;
+import akka.actor.IndirectActorProducer;
+import org.springframework.context.ApplicationContext;
+
+public class SpringActorProducer implements IndirectActorProducer {
+
+    private ApplicationContext applicationContext;
+
+    private String beanActorName;
+
+    public SpringActorProducer(ApplicationContext applicationContext, String beanActorName) {
+        this.applicationContext = applicationContext;
+        this.beanActorName = beanActorName;
+    }
+
+    @Override
+    public Actor produce() {
+        return (Actor) applicationContext.getBean(beanActorName);
+    }
+
+    @Override
+    public Class<? extends Actor> actorClass() {
+        return (Class<? extends Actor>) applicationContext.getType(beanActorName);
+    }
+
+}

akka-modules/spring-akka/src/main/java/com/baeldung/akka/SpringExtension.java

@@ -0,0 +1,32 @@
+package com.baeldung.akka;
+
+import akka.actor.AbstractExtensionId;
+import akka.actor.ExtendedActorSystem;
+import akka.actor.Extension;
+import akka.actor.Props;
+import org.springframework.context.ApplicationContext;
+
+public class SpringExtension extends AbstractExtensionId<SpringExtension.SpringExt> {
+
+    public static final SpringExtension SPRING_EXTENSION_PROVIDER = new SpringExtension();
+
+    @Override
+    public SpringExt createExtension(ExtendedActorSystem system) {
+        return new SpringExt();
+    }
+
+    public static class SpringExt implements Extension {
+
+        private volatile ApplicationContext applicationContext;
+
+        public void initialize(ApplicationContext applicationContext) {
+            this.applicationContext = applicationContext;
+        }
+
+        public Props props(String actorBeanName) {
+            return Props.create(SpringActorProducer.class, applicationContext, actorBeanName);
+        }
+
+    }
+
+}

akka-modules/spring-akka/src/main/resources/logback.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<configuration>
+    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
+        <encoder>
+            <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n
+            </pattern>
+        </encoder>
+    </appender>
+
+    <root level="INFO">
+        <appender-ref ref="STDOUT" />
+    </root>
+</configuration>

akka-modules/spring-akka/src/test/java/com/baeldung/akka/SpringAkkaIntegrationTest.java

@@ -0,0 +1,46 @@
+package com.baeldung.akka;
+
+import java.util.concurrent.TimeUnit;
+
+import akka.actor.ActorRef;
+import akka.actor.ActorSystem;
+import akka.util.Timeout;
+import com.baeldung.akka.GreetingActor.Greet;
+import org.junit.After;
+import org.junit.Assert;
+import org.junit.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.test.context.ContextConfiguration;
+import org.springframework.test.context.junit4.AbstractJUnit4SpringContextTests;
+import scala.concurrent.Await;
+import scala.concurrent.Future;
+import scala.concurrent.duration.FiniteDuration;
+
+import static akka.pattern.Patterns.ask;
+import static com.baeldung.akka.SpringExtension.SPRING_EXTENSION_PROVIDER;
+
+@ContextConfiguration(classes = AppConfiguration.class)
+public class SpringAkkaIntegrationTest extends AbstractJUnit4SpringContextTests {
+
+    @Autowired
+    private ActorSystem system;
+
+    @Test
+    public void whenCallingGreetingActor_thenActorGreetsTheCaller() throws Exception {
+        ActorRef greeter = system.actorOf(SPRING_EXTENSION_PROVIDER.get(system).props("greetingActor"), "greeter");
+
+        FiniteDuration duration = FiniteDuration.create(1, TimeUnit.SECONDS);
+        Timeout timeout = Timeout.durationToTimeout(duration);
+
+        Future<Object> result = ask(greeter, new Greet("John"), timeout);
+
+        Assert.assertEquals("Hello, John", Await.result(result, duration));
+    }
+
+    @After
+    public void tearDown() {
+        system.shutdown();
+        system.awaitTermination();
+    }
+
+}