Actors in java with akka

I am currently working my way through the akka tutorial, except that im using java instead of scala. I am also trying to make it in smaller steps, and trying to keep it runnable as much as possible. I have removed import statements and such to make it shorter, the full code can be found at github: http://github.com/bobo/akka_sample_java

Lets start withough any akka or other magic, except for Guice.
I started by creating a chatserver:

public class ChatServer {

    @Inject
    public ChatServer() {
    }

    private List<Message> messages = new ArrayList<Message>();
    private Set<ChatSession> sessions = new HashSet<ChatSession>();
    private Vector<byte[]> storage = new Vector<byte[]>();

    public void login(ChatSession chatSession) {
        sessions.add(chatSession);
    }

    public List<Message> getLog() {
        return Collections.unmodifiableList(messages);
    }

    public void sendMessage(Message message) {
        storeMessage(message);
        for (ChatSession chatSession : sessions) {
            chatSession.recieveMessage(message);
        }
    }

    private void storeMessage(Message message) {
        messages.add(message);
        storage.add(message.toString().getBytes());
    }
}

This is just a simple class, that stores messages in byteformat in a vector.
It might seem weird to have the Vector store byte[] instead of message, but later we will change it to a PersistentVector, and that uses byte[] to store it in the backend.

And we need some clients:

public class ChatSession {

    private String userName;
    private final List<Message> messages = new ArrayList<Message>();
    @Inject
    private ChatServer chatServer;

    public void login() {
        chatServer.login(this);
    }

    public void setUserName(String userName) {
        this.userName = userName;
    }

    public String getUserName() {
        return userName;
    }

    public void recieveMessage(Message message) {
        messages.add(message);
    }

    public void sendMessage(String text) {
        Message message = new Message(userName, text);
        chatServer.sendMessage(message);
    }

    public List<Message> getLog() {
        return messages;
    }
}

Here we inject the Chatserver with @Inject directly on the variable declaration

we can use it in a simple testcase:

public class IntegrationTest {
    Module m;
    @Before
    public void setup() {
        m = new AbstractModule() {
            @Override
            protected void configure() {
                bind(ChatSession.class);
                bind(ChatServer.class).asEagerSingleton();
            }
        };
    }

    @Test
    public void integrationTest() throws InterruptedException {
        Injector inj = Guice.createInjector(m);
        final ChatSession userOne = inj.getInstance(ChatSession.class);
        userOne.setUserName("userOne");
        userOne.login();
        final ChatSession userTwo = inj.getInstance(ChatSession.class);
        userTwo.setUserName("userTwo");
        userTwo.login();
        userOne.sendMessage("Hello");
        userTwo.sendMessage("Another Message 1");
        Thread.sleep(400); //wait for messages to finish
        assertEquals(2, userOne.getLog().size());
        assertEquals(2, userTwo.getLog().size());
        assertEquals(userTwo.getLog(), userOne.getLog());
    }
}

Here we create two chatsessions with our guice injector. And since we have bound ChatServer as a singleton they will have the same instance of chatserver injected.


Now the next step is to add akka to the project. i will add that to a seperate post