RxJava'ify

.gitignore

@@ -6,6 +6,7 @@
 /.idea/modules.xml
 /.idea/workspace.xml
 /.idea/caches/
+/.idea
 .DS_Store
 /build
 /captures

app/build.gradle

@@ -73,12 +73,10 @@ check.configure {
 dependencies {
 
     // Depend on the core project for XMPP related stuff
-    implementation(project(':xmpp_core'))
+    implementation project(':core')
 
     // Plug a Room based implementation into the persistence api
-    implementation(project(':persistence-room')) {
+    implementation project(':persistence-room')
-        transitive = true
-    }
 
     // Dagger 2 for dependency injection
     implementation "com.google.dagger:dagger:$daggerVersion"
@@ -93,7 +91,7 @@ dependencies {
     annotationProcessor "com.jakewharton:butterknife-compiler:$butterKnifeVersion"
 
     // support libraries
-    implementation 'androidx.appcompat:appcompat:1.1.0-beta01'
+    implementation "androidx.appcompat:appcompat:$appCompatVersion"
     implementation 'com.google.android.material:material:1.0.0'
     implementation 'androidx.legacy:legacy-support-v4:1.0.0'
     implementation 'androidx.vectordrawable:vectordrawable:1.0.1'
@@ -108,7 +106,7 @@ dependencies {
     implementation "org.igniterealtime.smack:smack-android-extensions:$smackAndroidExtensionsVersion"
 
     // Testing - as if...
-    testImplementation 'junit:junit:4.12'
+    testImplementation "junit:junit:$junitVersion"
-    androidTestImplementation 'androidx.test:runner:1.2.0'
+    androidTestImplementation "androidx.test:runner:$andxTestRunnerVersion"
-    androidTestImplementation 'androidx.test.espresso:espresso-core:3.2.0'
+    androidTestImplementation "androidx.test.espresso:espresso-core:$andxTestEspressoVersion"
 }

app/src/main/java/org/mercury_im/messenger/MercuryImApplication.java

@@ -10,8 +10,8 @@ import android.os.Build;
 import org.mercury_im.messenger.di.component.AppComponent;
 import org.mercury_im.messenger.di.component.DaggerAppComponent;
 import org.mercury_im.messenger.di.module.AppModule;
-import org.mercury_im.messenger.di.module.RepositoryModule;
+import org.mercury_im.messenger.persistence.room.RoomModule;
-import org.mercury_im.messenger.di.module.RoomModule;
+import org.mercury_im.messenger.persistence.room.RoomRepositoryModule;
 import org.mercury_im.messenger.service.XmppConnectionService;
 
 public class MercuryImApplication extends Application {
@@ -30,13 +30,9 @@ public class MercuryImApplication extends Application {
         super.onCreate();
 
         INSTANCE = this;
-        appComponent = DaggerAppComponent.builder()
-                .appModule(new AppModule(this))
-                .roomModule(new RoomModule(this))
-                .repositoryModule(new RepositoryModule())
-                .build();
 
-        appComponent.inject(this);
+        appComponent = createAppComponent();
+
         initializeNotificationChannels(this);
 
         Intent serviceIntent = new Intent(getApplicationContext(), XmppConnectionService.class);
@@ -49,6 +45,22 @@ public class MercuryImApplication extends Application {
         }
     }
 
+    /**
+     * Create the Dependency Injection graph.
+     * For testing, overwrite this method with custom modules.
+     */
+    public AppComponent createAppComponent() {
+        AppComponent appComponent = DaggerAppComponent.builder()
+                .appModule(new AppModule(this))
+                .roomModule(new RoomModule(this))
+                .roomRepositoryModule(new RoomRepositoryModule())
+                .build();
+
+        appComponent.inject(this);
+
+        return appComponent;
+    }
+
     public void initializeNotificationChannels(Context context) {
         // Only necessary on Android O and upwards.
         if (Build.VERSION.SDK_INT < 26) {

app/src/main/java/org/mercury_im/messenger/di/component/AppComponent.java

@@ -2,10 +2,9 @@ package org.mercury_im.messenger.di.component;
 
 import org.mercury_im.messenger.MercuryImApplication;
 import org.mercury_im.messenger.di.module.AppModule;
-import org.mercury_im.messenger.di.module.RepositoryModule;
-import org.mercury_im.messenger.di.module.RoomModule;
 import org.mercury_im.messenger.handler.RoomPlainMessageHandler;
 import org.mercury_im.messenger.handler.RoomRosterHandler;
+import org.mercury_im.messenger.persistence.room.RoomModule;
 import org.mercury_im.messenger.service.XmppConnectionService;
 import org.mercury_im.messenger.ui.MainActivity;
 import org.mercury_im.messenger.ui.chat.ChatActivity;
@@ -23,7 +22,7 @@ import javax.inject.Singleton;
 import dagger.Component;
 
 @Singleton
-@Component(modules = {AppModule.class, RoomModule.class, RepositoryModule.class})
+@Component(modules = {AppModule.class, RoomModule.class})
 public interface AppComponent {
 
     // Application

app/src/main/java/org/mercury_im/messenger/di/module/AppModule.java

@@ -1,5 +1,7 @@
 package org.mercury_im.messenger.di.module;
 
+import android.app.Application;
+
 import org.mercury_im.messenger.MercuryImApplication;
 
 import javax.inject.Singleton;
@@ -18,7 +20,7 @@ public class AppModule {
 
     @Provides
     @Singleton
-    MercuryImApplication provideApplication() {
+    Application provideApplication() {
         return mApplication;
     }
 }

app/src/main/java/org/mercury_im/messenger/handler/RoomPlainMessageHandler.java

@@ -10,12 +10,14 @@ import org.mercury_im.messenger.MercuryImApplication;
 import org.mercury_im.messenger.persistence.model.MessageModel;
 import org.mercury_im.messenger.persistence.repository.MessageRepository;
 import org.mercury_im.messenger.persistence.room.model.RoomMessageModel;
-import org.mercury_im.messenger.xmpp_core.PlainMessageHandler;
+import org.mercury_im.messenger.core.PlainMessageHandler;
 
 import java.util.Date;
 
 import javax.inject.Inject;
 
+import io.reactivex.Single;
+
 import static org.mercury_im.messenger.MercuryImApplication.TAG;
 
 public class RoomPlainMessageHandler implements PlainMessageHandler {
@@ -43,8 +45,9 @@ public class RoomPlainMessageHandler implements PlainMessageHandler {
         messageModel.setIncoming(true);
         messageModel.setBody(message.getBody());
         messageModel.setSendDate(new Date());
-        long messageId = messageRepository.insertMessage(messageModel);
+        Single<Long> messageId = messageRepository.insertMessage(messageModel);
-        Log.d(TAG, "Inserted incoming message " + messageId);
+
+        Log.d(TAG, "Inserted incoming message " + messageId.blockingGet());
     }
 
     @Override
@@ -56,8 +59,8 @@ public class RoomPlainMessageHandler implements PlainMessageHandler {
         messageModel.setIncoming(false);
         messageModel.setBody(message.getBody());
         messageModel.setSendDate(new Date());
-        long messageId = messageRepository.insertMessage(messageModel);
+        Single<Long> messageId = messageRepository.insertMessage(messageModel);
-        Log.d(TAG, "Inserted outgoing message " + messageId);
+        Log.d(TAG, "Inserted outgoing message " + messageId.blockingGet());
     }
 
     @Override
@@ -75,7 +78,7 @@ public class RoomPlainMessageHandler implements PlainMessageHandler {
 
         messageModel.setBody(carbonCopy.getBody());
         messageModel.setSendDate(new Date());
-        long messageId = messageRepository.insertMessage(messageModel);
+        Single<Long> messageId = messageRepository.insertMessage(messageModel);
-        Log.d(TAG, "Inserted carbon message " + messageId);
+        Log.d(TAG, "Inserted carbon message " + messageId.blockingGet());
     }
 }

app/src/main/java/org/mercury_im/messenger/handler/RoomRosterHandler.java

@@ -15,8 +15,8 @@ import org.mercury_im.messenger.persistence.room.dao.ContactAttributesDao;
 import org.mercury_im.messenger.persistence.room.dao.EntityDao;
 import org.mercury_im.messenger.persistence.room.model.RoomContactAttributes;
 import org.mercury_im.messenger.persistence.room.model.RoomEntityModel;
-import org.mercury_im.messenger.xmpp_core.MercuryConnection;
+import org.mercury_im.messenger.core.MercuryConnection;
-import org.mercury_im.messenger.xmpp_core.RosterHandler;
+import org.mercury_im.messenger.core.RosterHandler;
 
 import java.util.Collection;
 

app/src/main/java/org/mercury_im/messenger/ui/BindingActivity.java

@@ -1,55 +0,0 @@
-package org.mercury_im.messenger.ui;
-
-import android.content.ComponentName;
-import android.content.Context;
-import android.content.Intent;
-import android.content.ServiceConnection;
-import android.os.IBinder;
-
-import androidx.appcompat.app.AppCompatActivity;
-
-import org.mercury_im.messenger.service.XmppConnectionService;
-
-public abstract class BindingActivity extends AppCompatActivity {
-
-    protected XmppConnectionService connectionService;
-    protected boolean bound;
-
-    @Override
-    protected void onStart() {
-        super.onStart();
-        Intent intent = new Intent(this, XmppConnectionService.class);
-        bindService(intent, serviceConnection, Context.BIND_AUTO_CREATE);
-    }
-
-    @Override
-    protected void onStop() {
-        super.onStop();
-        unbindService(serviceConnection);
-        bound = false;
-    }
-
-    protected void onServiceBound() {
-
-    }
-
-    protected void onServiceUnbound() {
-
-    }
-
-    private ServiceConnection serviceConnection = new ServiceConnection() {
-        @Override
-        public void onServiceConnected(ComponentName componentName, IBinder iBinder) {
-            XmppConnectionService.Binder binder = (XmppConnectionService.Binder) iBinder;
-            connectionService = binder.getService();
-            bound = true;
-            onServiceBound();
-        }
-
-        @Override
-        public void onServiceDisconnected(ComponentName componentName) {
-            bound = false;
-            onServiceUnbound();
-        }
-    };
-}

app/src/main/java/org/mercury_im/messenger/ui/MainActivity.java

@@ -6,6 +6,7 @@ import android.view.Menu;
 import android.view.MenuItem;
 
 import androidx.annotation.Nullable;
+import androidx.appcompat.app.AppCompatActivity;
 import androidx.appcompat.widget.Toolbar;
 import androidx.lifecycle.Observer;
 
@@ -24,14 +25,7 @@ import java.util.List;
 
 import javax.inject.Inject;
 
-public class MainActivity extends BindingActivity {
+public class MainActivity extends AppCompatActivity {
-
-
-    @Inject
-    public AccountRepository accountRepository;
-
-    @Inject
-    public ContactAttributesRepository contactAttributesRepository;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -43,15 +37,6 @@ public class MainActivity extends BindingActivity {
         MercuryImApplication.getApplication().getAppComponent().inject(this);
 
         FloatingActionButton fab = findViewById(R.id.fab);
-
-        accountRepository.getAllAccountsLive().observe(this, new Observer<List<AccountModel>>() {
-            @Override
-            public void onChanged(@Nullable List<AccountModel> accountModels) {
-                if (accountModels == null || accountModels.isEmpty()) {
-                    startActivity(new Intent(getApplicationContext(), LoginActivity.class));
-                }
-            }
-        });
     }
 
     @Override

app/src/main/java/org/mercury_im/messenger/ui/chat/ChatActivity.java

@@ -11,8 +11,6 @@ import androidx.lifecycle.ViewModelProviders;
 import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
 
-import org.jivesoftware.smack.SmackException;
-import org.jivesoftware.smack.chat2.ChatManager;
 import org.jxmpp.jid.EntityBareJid;
 import org.jxmpp.jid.impl.JidCreate;
 import org.mercury_im.messenger.MercuryImApplication;
@@ -21,7 +19,6 @@ import org.mercury_im.messenger.persistence.model.AccountModel;
 import org.mercury_im.messenger.persistence.model.MessageModel;
 import org.mercury_im.messenger.persistence.repository.AccountRepository;
 import org.mercury_im.messenger.persistence.repository.MessageRepository;
-import org.mercury_im.messenger.ui.BindingActivity;
 
 import java.util.List;
 

app/src/main/java/org/mercury_im/messenger/ui/login/AccountsActivity.java

@@ -6,21 +6,14 @@ import android.os.Bundle;
 import android.view.LayoutInflater;
 import android.view.View;
 
-import androidx.fragment.app.FragmentActivity;
+import androidx.appcompat.app.AppCompatActivity;
 
 import org.mercury_im.messenger.MercuryImApplication;
 import org.mercury_im.messenger.R;
 import org.mercury_im.messenger.persistence.model.AccountModel;
-import org.mercury_im.messenger.persistence.repository.AccountRepository;
-import org.mercury_im.messenger.service.XmppConnectionService;
-import org.mercury_im.messenger.ui.BindingActivity;
 
-import javax.inject.Inject;
+public class AccountsActivity extends AppCompatActivity
-
+        implements AccountsFragment.OnListFragmentInteractionListener {
-public class AccountsActivity extends BindingActivity implements AccountsFragment.OnListFragmentInteractionListener {
-
-    @Inject
-    AccountRepository accountRepository;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -44,13 +37,4 @@ public class AccountsActivity extends BindingActivity implements AccountsFragmen
                 });
         builder.create().show();
     }
-
-    @Override
-    protected void onServiceBound() {
-        super.onServiceBound();
-    }
-
-    public XmppConnectionService getConnectionService() {
-        return connectionService;
-    }
 }

app/src/main/java/org/mercury_im/messenger/ui/login/AccountsFragment.java

@@ -3,13 +3,11 @@ package org.mercury_im.messenger.ui.login;
 import android.content.Context;
 import android.os.Bundle;
 import android.util.Log;
-import android.util.LongSparseArray;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.ViewGroup;
 
 import androidx.fragment.app.Fragment;
-import androidx.lifecycle.Observer;
 import androidx.lifecycle.ViewModelProviders;
 import androidx.recyclerview.widget.LinearLayoutManager;
 import androidx.recyclerview.widget.RecyclerView;
@@ -17,8 +15,6 @@ import androidx.recyclerview.widget.RecyclerView;
 import org.mercury_im.messenger.MercuryImApplication;
 import org.mercury_im.messenger.R;
 import org.mercury_im.messenger.persistence.model.AccountModel;
-import org.mercury_im.messenger.service.XmppConnectionService;
-import org.mercury_im.messenger.xmpp_core.ConnectionState;
 
 /**
  * A fragment representing a list of Items.

app/src/main/java/org/mercury_im/messenger/ui/login/AccountsViewModel.java

@@ -22,7 +22,7 @@ public class AccountsViewModel extends ViewModel {
     public AccountsViewModel() {
         super();
         MercuryImApplication.getApplication().getAppComponent().inject(this);
-        accounts = repository.getAllAccountsLive();
+        accounts = repository.getAllAccounts();
     }
 
     public LiveData<List<RoomAccountModel>> getAccounts() {

app/src/main/java/org/mercury_im/messenger/ui/login/LoginActivity.java

@@ -9,6 +9,7 @@ import android.view.inputmethod.EditorInfo;
 import android.widget.Button;
 import android.widget.TextView;
 
+import androidx.appcompat.app.AppCompatActivity;
 import androidx.lifecycle.LiveData;
 import androidx.lifecycle.ViewModelProviders;
 
@@ -28,8 +29,7 @@ import org.mercury_im.messenger.handler.RoomRosterHandler;
 import org.mercury_im.messenger.persistence.model.AccountModel;
 import org.mercury_im.messenger.persistence.repository.AccountRepository;
 import org.mercury_im.messenger.persistence.room.model.RoomAccountModel;
-import org.mercury_im.messenger.ui.BindingActivity;
+import org.mercury_im.messenger.core.MercuryConnection;
-import org.mercury_im.messenger.xmpp_core.MercuryConnection;
 
 import java.io.IOException;
 
@@ -37,11 +37,17 @@ import javax.inject.Inject;
 
 import butterknife.BindView;
 import butterknife.ButterKnife;
+import io.reactivex.Single;
+import io.reactivex.SingleObserver;
+import io.reactivex.android.schedulers.AndroidSchedulers;
+import io.reactivex.disposables.CompositeDisposable;
+import io.reactivex.disposables.Disposable;
+import io.reactivex.schedulers.Schedulers;
 
 /**
  * A login screen that offers login via email/password.
  */
-public class LoginActivity extends BindingActivity implements TextView.OnEditorActionListener {
+public class LoginActivity extends AppCompatActivity implements TextView.OnEditorActionListener {
 
     @Inject
     AccountRepository accountRepository;
@@ -83,18 +89,6 @@ public class LoginActivity extends BindingActivity implements TextView.OnEditorA
         mSignInView.setEnabled(false);
     }
 
-    @Override
-    protected void onServiceBound() {
-        super.onServiceBound();
-        mSignInView.setEnabled(true);
-    }
-
-    @Override
-    protected void onServiceUnbound() {
-        super.onServiceUnbound();
-        mSignInView.setEnabled(false);
-    }
-
     private void displayCredentials(LiveData<? extends AccountModel> account) {
         account.observe(this, accountModel -> {
             if (accountModel == null) {
@@ -137,7 +131,25 @@ public class LoginActivity extends BindingActivity implements TextView.OnEditorA
             accountModel.setEnabled(true);
             accountModel.setJid(jid);
             accountModel.setPassword(password);
-            long id = accountRepository.insertAccount(accountModel);
+            Single<Long> id = accountRepository.insertAccount(accountModel);
+            id.subscribeOn(Schedulers.io())
+                    .observeOn(AndroidSchedulers.mainThread())
+                    .subscribe(new SingleObserver<Long>() {
+                        @Override
+                        public void onSubscribe(Disposable d) {
+
+                        }
+
+                        @Override
+                        public void onSuccess(Long aLong) {
+
+                        }
+
+                        @Override
+                        public void onError(Throwable e) {
+
+                        }
+                    });
             accountModel.setId(id);
             Log.d(MercuryImApplication.TAG, "LoginActivity.loginDetailsEntered: Account " + id + " inserted.");
             attemptLogin(accountModel);

app/src/main/java/org/mercury_im/messenger/ui/roster/RosterViewModel.java

@@ -1,10 +1,8 @@
 package org.mercury_im.messenger.ui.roster;
 
-import android.app.Application;
-
-import androidx.annotation.NonNull;
-import androidx.lifecycle.AndroidViewModel;
 import androidx.lifecycle.LiveData;
+import androidx.lifecycle.MutableLiveData;
+import androidx.lifecycle.ViewModel;
 
 import org.mercury_im.messenger.MercuryImApplication;
 import org.mercury_im.messenger.persistence.repository.ContactRepository;
@@ -14,18 +12,34 @@ import java.util.List;
 
 import javax.inject.Inject;
 
-public class RosterViewModel extends AndroidViewModel {
+import io.reactivex.android.schedulers.AndroidSchedulers;
+import io.reactivex.disposables.CompositeDisposable;
+import io.reactivex.functions.Consumer;
+import io.reactivex.schedulers.Schedulers;
+
+public class RosterViewModel extends ViewModel {
 
     @Inject
-    ContactRepository contactRepository;
+    ContactRepository<RoomContactModel> contactRepository;
 
-    private final LiveData<List<RoomContactModel>> rosterEntryList;
+    private final MutableLiveData<List<RoomContactModel>> rosterEntryList = new MutableLiveData<>();
+    private final CompositeDisposable compositeDisposable = new CompositeDisposable();
 
-    @Inject
+    public RosterViewModel() {
-    public RosterViewModel(@NonNull Application application) {
+        super();
-        super(application);
         MercuryImApplication.getApplication().getAppComponent().inject(this);
-        this.rosterEntryList = contactRepository.getAllContacts();
+
+        // Subscribe to changes to the contacts table and update the LiveData object for the UI.
+        compositeDisposable.add(contactRepository.getAllContacts()
+                .subscribeOn(Schedulers.io())
+                .observeOn(AndroidSchedulers.mainThread())
+                .subscribe(rosterEntryList::setValue));
+    }
+
+    @Override
+    protected void onCleared() {
+        super.onCleared();
+        compositeDisposable.clear();
     }
 
     public LiveData<List<RoomContactModel>> getRosterEntryList() {

core/build.gradle

@@ -2,6 +2,8 @@ apply plugin: 'java-library'
 
 dependencies {
 
+    api project(":persistence")
+
     // Smack
     // Not all of those are needed, but it may be a good idea to define those versions explicitly
     api "org.igniterealtime.smack:smack-core:$smackCoreVersion"
@@ -18,6 +20,8 @@ dependencies {
     // Dagger 2 for dependency injection
     implementation "com.google.dagger:dagger:$daggerVersion"
     annotationProcessor "com.google.dagger:dagger-compiler:$daggerVersion"
+
+    testImplementation "junit:junit:$junitVersion"
 }
 
 sourceCompatibility = "8"

core/src/main/java/org/mercury_im/messenger/core/ConnectionCenter.java

@@ -1,8 +1,11 @@
-package org.mercury_im.messenger.xmpp_core;
+package org.mercury_im.messenger.core;
 
 import java.util.HashMap;
 import java.util.Map;
 
+import javax.inject.Singleton;
+
+@Singleton
 public class ConnectionCenter {
 
     private static ConnectionCenter INSTANCE;
@@ -20,6 +23,8 @@ public class ConnectionCenter {
         return INSTANCE;
     }
 
+
+
     public MercuryConnection getConnection(long accountId) {
         return connectionMap.get(accountId);
     }

core/src/main/java/org/mercury_im/messenger/core/ConnectionState.java

@@ -1,4 +1,4 @@
-package org.mercury_im.messenger.xmpp_core;
+package org.mercury_im.messenger.core;
 
 /**
  * {@link MercuryConnection} modeled as a finite state machine.

core/src/main/java/org/mercury_im/messenger/core/IRosterHandler.java

@@ -0,0 +1,84 @@
+package org.mercury_im.messenger.core;
+
+import org.jivesoftware.smack.packet.Presence;
+import org.jivesoftware.smack.roster.Roster;
+import org.jivesoftware.smack.roster.packet.RosterPacket;
+import org.jxmpp.jid.BareJid;
+import org.jxmpp.jid.FullJid;
+import org.jxmpp.jid.Jid;
+
+import java.util.Collection;
+import java.util.List;
+
+public class IRosterHandler implements RosterHandler {
+
+    @Override
+    public void presenceAvailable(FullJid address, Presence availablePresence) {
+
+    }
+
+    @Override
+    public void presenceUnavailable(FullJid address, Presence presence) {
+
+    }
+
+    @Override
+    public void presenceError(Jid address, Presence errorPresence) {
+
+    }
+
+    @Override
+    public void presenceSubscribed(BareJid address, Presence subscribedPresence) {
+
+    }
+
+    @Override
+    public void presenceUnsubscribed(BareJid address, Presence unsubscribedPresence) {
+
+    }
+
+    @Override
+    public void onRosterLoaded(Roster roster) {
+
+    }
+
+    @Override
+    public void onRosterLoadingFailed(Exception exception) {
+
+    }
+
+    @Override
+    public List<RosterPacket.Item> getEntries() {
+        return null;
+    }
+
+    @Override
+    public RosterPacket.Item getEntry(Jid bareJid) {
+        return null;
+    }
+
+    @Override
+    public String getRosterVersion() {
+        return null;
+    }
+
+    @Override
+    public boolean addEntry(RosterPacket.Item item, String version) {
+        return false;
+    }
+
+    @Override
+    public boolean resetEntries(Collection<RosterPacket.Item> items, String version) {
+        return false;
+    }
+
+    @Override
+    public boolean removeEntry(Jid bareJid, String version) {
+        return false;
+    }
+
+    @Override
+    public void resetStore() {
+
+    }
+}

core/src/main/java/org/mercury_im/messenger/core/MercuryConnection.java

@@ -1,27 +1,20 @@
-package org.mercury_im.messenger.xmpp_core;
+package org.mercury_im.messenger.core;
 
 import org.jivesoftware.smack.AbstractXMPPConnection;
 import org.jivesoftware.smack.ConnectionListener;
-import org.jivesoftware.smack.ReconnectionListener;
 import org.jivesoftware.smack.ReconnectionManager;
-import org.jivesoftware.smack.SmackException;
 import org.jivesoftware.smack.XMPPConnection;
-import org.jivesoftware.smack.XMPPException;
 import org.jivesoftware.smack.chat2.ChatManager;
 import org.jivesoftware.smack.iqrequest.AbstractIqRequestHandler;
 import org.jivesoftware.smack.iqrequest.IQRequestHandler;
 import org.jivesoftware.smack.packet.IQ;
 import org.jivesoftware.smack.roster.Roster;
-import org.jivesoftware.smack.sm.packet.StreamManagement;
-import org.jivesoftware.smack.tcp.XMPPTCPConnection;
 import org.jivesoftware.smackx.carbons.CarbonManager;
-import org.jivesoftware.smackx.csi.ClientStateIndicationManager;
 import org.jivesoftware.smackx.disco.ServiceDiscoveryManager;
 import org.jivesoftware.smackx.disco.packet.DiscoverInfo;
 import org.jivesoftware.smackx.iqversion.packet.Version;
 import org.jivesoftware.smackx.sid.StableUniqueStanzaIdManager;
 
-import java.io.IOException;
 import java.util.logging.Logger;
 
 public class MercuryConnection implements ConnectionListener {
@@ -70,11 +63,6 @@ public class MercuryConnection implements ConnectionListener {
         return connection;
     }
 
-    public void setRosterHandler(RosterHandler handler) {
-        roster.addRosterListener(handler);
-        roster.addRosterLoadedListener(handler);
-    }
-
     public void setPlainMessageHandler(PlainMessageHandler plainMessageHandler) {
         carbonManager.addCarbonCopyReceivedListener(plainMessageHandler);
         chatManager.addIncomingListener(plainMessageHandler);

core/src/main/java/org/mercury_im/messenger/core/PlainMessageHandler.java

@@ -1,4 +1,4 @@
-package org.mercury_im.messenger.xmpp_core;
+package org.mercury_im.messenger.core;
 
 import org.jivesoftware.smack.chat2.IncomingChatMessageListener;
 import org.jivesoftware.smack.chat2.OutgoingChatMessageListener;

core/src/main/java/org/mercury_im/messenger/core/RosterHandler.java

@@ -0,0 +1,9 @@
+package org.mercury_im.messenger.core;
+
+import org.jivesoftware.smack.roster.PresenceEventListener;
+import org.jivesoftware.smack.roster.RosterLoadedListener;
+import org.jivesoftware.smack.roster.rosterstore.RosterStore;
+
+public interface RosterHandler extends RosterStore, RosterLoadedListener, PresenceEventListener {
+
+}

core/src/main/java/org/mercury_im/messenger/core/di/CenterModule.java

@@ -0,0 +1,20 @@
+package org.mercury_im.messenger.core.di;
+
+import org.mercury_im.messenger.core.ConnectionCenter;
+
+import javax.inject.Singleton;
+
+import dagger.Module;
+import dagger.Provides;
+
+@Module
+public class CenterModule {
+
+    @Singleton
+    @Provides
+    static ConnectionCenter provideConnectionCenter() {
+        return ConnectionCenter.get();
+    }
+
+
+}

core/src/main/java/org/mercury_im/messenger/core/di/HandlerModule.java

@@ -0,0 +1,16 @@
+package org.mercury_im.messenger.core.di;
+
+import org.mercury_im.messenger.core.IRosterHandler;
+import org.mercury_im.messenger.core.RosterHandler;
+
+import dagger.Module;
+import dagger.Provides;
+
+@Module
+public class HandlerModule {
+
+    @Provides
+    RosterHandler provideRosterHandler() {
+        return new IRosterHandler();
+    }
+}

core/src/main/java/org/mercury_im/messenger/core/di/XmppComponent.java

@@ -0,0 +1,11 @@
+package org.mercury_im.messenger.core.di;
+
+import javax.inject.Singleton;
+
+import dagger.Component;
+
+@Singleton
+@Component(modules = CenterModule.class)
+public interface XmppComponent {
+
+}

persistence-room/build.gradle

@@ -36,16 +36,15 @@ dependencies {
     implementation "com.google.dagger:dagger:$daggerVersion"
     annotationProcessor "com.google.dagger:dagger-compiler:$daggerVersion"
 
-    implementation fileTree(dir: 'libs', include: ['*.jar'])
+    testImplementation "junit:junit:$junitVersion"
-
+    androidTestImplementation "androidx.test:runner:$andxTestRunnerVersion"
-    implementation 'androidx.appcompat:appcompat:1.0.2'
+    androidTestImplementation "androidx.test.espresso:espresso-core:$andxTestEspressoVersion"
-    testImplementation 'junit:junit:4.12'
+    androidTestImplementation "androidx.test:core:$andxTestCoreVersion"
-    androidTestImplementation 'androidx.test:runner:1.1.1'
+    androidTestImplementation "androidx.test.ext:junit:$andxTestJunitVersion"
-    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
-    androidTestImplementation "androidx.test:core:1.2.0"
-    androidTestImplementation 'androidx.test.ext:junit:1.1.1'
 
     // Room
     api "androidx.room:room-runtime:$roomVersion"
     annotationProcessor "androidx.room:room-compiler:$roomVersion"
+    implementation "androidx.room:room-rxjava2:$roomRxJavaVersion"
+    api "io.reactivex.rxjava2:rxandroid:$rxAndroidVersion"
 }

persistence-room/src/androidTest/java/org/mercury_im/messenger/persistence/room/ExampleInstrumentedTest.java

@@ -1,14 +1,15 @@
 package org.mercury_im.messenger.persistence.room;
 
 import android.content.Context;
+import android.util.Log;
 
-import androidx.lifecycle.LiveData;
 import androidx.test.core.app.ApplicationProvider;
 import androidx.test.ext.junit.runners.AndroidJUnit4;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.jxmpp.jid.impl.JidCreate;
+import org.mercury_im.messenger.persistence.model.AccountModel;
 import org.mercury_im.messenger.persistence.room.model.RoomAccountModel;
 import org.mercury_im.messenger.persistence.room.repository.IAccountRepository;
 import org.mercury_im.messenger.persistence.room.repository.IContactAttributesRepository;
@@ -16,7 +17,13 @@ import org.mercury_im.messenger.persistence.room.repository.IMessageRepository;
 
 import java.util.List;
 
-import static org.junit.Assert.assertNull;
+import io.reactivex.Observable;
+import io.reactivex.android.schedulers.AndroidSchedulers;
+import io.reactivex.functions.Predicate;
+import io.reactivex.observers.DefaultObserver;
+import io.reactivex.schedulers.Schedulers;
+
+import static org.junit.Assert.assertEquals;
 
 /**
  * Instrumented test, which will execute on an Android device.
@@ -37,13 +44,20 @@ public class ExampleInstrumentedTest {
         IContactAttributesRepository rosterRepository = new IContactAttributesRepository(appDatabase.rosterEntryDao());
         IMessageRepository messageRepository = new IMessageRepository(appDatabase.messageDao());
 
-        LiveData<List<RoomAccountModel>> accounts = accountRepository.getAllAccountsLive();
+        Observable<List<RoomAccountModel>> accounts = accountRepository.getAllAccounts();
-        assertNull(accounts.getValue());
 
-        RoomAccountModel a1 = new RoomAccountModel();
+        final RoomAccountModel a1 = new RoomAccountModel();
         a1.setJid(JidCreate.entityBareFromOrThrowUnchecked("alice@wonderland.lit"));
         a1.setPassword("5w0rdf1sh");
         a1.setEnabled(false);
         accountRepository.insertAccount(a1);
+
+        accounts.test()
+                .assertValue(new Predicate<List<RoomAccountModel>>() {
+                    @Override
+                    public boolean test(List<RoomAccountModel> roomAccountModels) throws Exception {
+                        return roomAccountModels.size() == 1;
+                    }
+                });
     }
 }

persistence-room/src/main/java/org/mercury_im/messenger/persistence/room/RoomModule.java

@@ -1,7 +1,7 @@
-package org.mercury_im.messenger.di.module;
+package org.mercury_im.messenger.persistence.room;
+
+import android.app.Application;
 
-import org.mercury_im.messenger.MercuryImApplication;
-import org.mercury_im.messenger.persistence.room.AppDatabase;
 import org.mercury_im.messenger.persistence.room.dao.AccountDao;
 import org.mercury_im.messenger.persistence.room.dao.ChatDao;
 import org.mercury_im.messenger.persistence.room.dao.ContactDao;
@@ -18,13 +18,13 @@ import dagger.Provides;
 /**
  * Provides the {@link AppDatabase}, DAOs and Repositories.
  */
-@Module
+@Module(includes = RoomRepositoryModule.class)
 public class RoomModule {
 
     private AppDatabase mAppDatabase;
 
     @Inject
-    public RoomModule(MercuryImApplication application) {
+    public RoomModule(Application application) {
         mAppDatabase = AppDatabase.getDatabase(application);
     }
 

persistence-room/src/main/java/org/mercury_im/messenger/persistence/room/RoomRepositoryModule.java

@@ -1,4 +1,4 @@
-package org.mercury_im.messenger.di.module;
+package org.mercury_im.messenger.persistence.room;
 
 import org.mercury_im.messenger.persistence.repository.AccountRepository;
 import org.mercury_im.messenger.persistence.repository.ChatRepository;
@@ -25,7 +25,7 @@ import dagger.Module;
 import dagger.Provides;
 
 @Module
-public class RepositoryModule {
+public class RoomRepositoryModule {
 
     @Singleton
     @Provides

persistence-room/src/main/java/org/mercury_im/messenger/persistence/room/dao/AccountDao.java

@@ -1,40 +1,33 @@
 package org.mercury_im.messenger.persistence.room.dao;
 
-import androidx.lifecycle.LiveData;
 import androidx.annotation.WorkerThread;
 import androidx.room.Dao;
-import androidx.room.Delete;
-import androidx.room.Insert;
 import androidx.room.Query;
-import androidx.room.Transaction;
 import androidx.room.TypeConverters;
-import androidx.room.Update;
 
 import org.jxmpp.jid.EntityBareJid;
-import org.mercury_im.messenger.persistence.model.AccountModel;
 import org.mercury_im.messenger.persistence.room.model.RoomAccountModel;
 import org.mercury_im.messenger.persistence.room.type_converter.EntityBareJidConverter;
 
 import java.util.List;
 
+import io.reactivex.Completable;
+import io.reactivex.Maybe;
+import io.reactivex.Observable;
+
 @Dao
 @TypeConverters(EntityBareJidConverter.class)
 @WorkerThread
 public interface AccountDao extends BaseDao<RoomAccountModel> {
 
     /**
-     * Return a {@link LiveData} wrapping a {@link List} which contains all
+     * Return an {@link Observable} wrapping a {@link List} which contains all
      * {@link RoomAccountModel Accounts} which are currently stored in the database.
      *
      * @return live updating account list
      */
     @Query("select * from accounts")
-    LiveData<List<RoomAccountModel>> getAllAccountsLive();
+    Observable<List<RoomAccountModel>> getAllAccounts();
-
-    @Query("select * from accounts")
-    List<RoomAccountModel> getAllAccounts();
-
-
 
     /**
      * Return the {@link RoomAccountModel Account} which is identified by the given id.
@@ -43,11 +36,11 @@ public interface AccountDao extends BaseDao<RoomAccountModel> {
      * @return account or null
      */
     @Query("select * from accounts where pk_account_id = :id")
-    LiveData<RoomAccountModel> getAccountById(long id);
+    Maybe<RoomAccountModel> getAccountById(long id);
 
     @Query("select * from accounts where jid = :jid")
-    LiveData<RoomAccountModel> getAccountByJid(EntityBareJid jid);
+    Maybe<RoomAccountModel> getAccountByJid(EntityBareJid jid);
 
     @Query("update accounts set state = :state where pk_account_id = :accountId")
-    void updateConnectionState(long accountId, String state);
+    Completable updateConnectionState(long accountId, String state);
 }

persistence-room/src/main/java/org/mercury_im/messenger/persistence/room/dao/BaseDao.java

@@ -4,20 +4,23 @@ import androidx.room.Delete;
 import androidx.room.Insert;
 import androidx.room.Update;
 
+import io.reactivex.Completable;
+import io.reactivex.Single;
+
 public interface BaseDao<T> {
 
     @Insert
-    long insert(T entity);
+    Single<Long> insert(T entity);
 
     @Update
-    void update(T entity);
+    Completable update(T entity);
 
     @Update
-    void update(T[] entities);
+    Completable update(T[] entities);
 
     @Delete
-    void delete(T entity);
+    Completable delete(T entity);
 
     @Delete
-    void delete(T[] entities);
+    Completable delete(T[] entities);
 }

persistence-room/src/main/java/org/mercury_im/messenger/persistence/room/dao/ChatDao.java

@@ -1,6 +1,5 @@
 package org.mercury_im.messenger.persistence.room.dao;
 
-import androidx.lifecycle.LiveData;
 import androidx.room.Dao;
 import androidx.room.Query;
 import androidx.room.TypeConverters;
@@ -11,22 +10,25 @@ import org.mercury_im.messenger.persistence.room.type_converter.EntityBareJidCon
 
 import java.util.List;
 
+import io.reactivex.Maybe;
+import io.reactivex.Observable;
+
 @Dao
 @TypeConverters(EntityBareJidConverter.class)
 public interface ChatDao extends BaseDao<RoomChatModel> {
 
     @Query("SELECT * FROM chats")
-    LiveData<List<RoomChatModel>> getAllChats();
+    Observable<List<RoomChatModel>> getAllChats();
 
     @Query("SELECT chats.* FROM chats JOIN entities WHERE fk_account_id = :accountId")
-    LiveData<List<RoomChatModel>> getAllChatsOf(long accountId);
+    Observable<List<RoomChatModel>> getAllChatsOf(long accountId);
 
     @Query("SELECT * FROM chats WHERE fk_entity_id = :entityId")
-    LiveData<RoomChatModel> getChatWithIdentity(long entityId);
+    Maybe<RoomChatModel> getChatWithIdentity(long entityId);
 
     @Query("SELECT chats.* FROM chats JOIN entities WHERE fk_account_id = :accountId AND jid = :jid")
-    LiveData<RoomChatModel> getChatWithJid(long accountId, EntityBareJid jid);
+    Maybe<RoomChatModel> getChatWithJid(long accountId, EntityBareJid jid);
 
     @Query("SELECT chats.* FROM chats JOIN contacts WHERE contacts.pk_contact_id = :contactId")
-    LiveData<RoomChatModel> getChatWithContact(long contactId);
+    Maybe<RoomChatModel> getChatWithContact(long contactId);
 }

persistence-room/src/main/java/org/mercury_im/messenger/persistence/room/dao/ContactAttributesDao.java

@@ -1,6 +1,5 @@
 package org.mercury_im.messenger.persistence.room.dao;
 
-import androidx.lifecycle.LiveData;
 import androidx.room.Dao;
 import androidx.room.Insert;
 import androidx.room.Query;
@@ -12,6 +11,10 @@ import org.mercury_im.messenger.persistence.room.type_converter.EntityBareJidCon
 
 import java.util.List;
 
+import io.reactivex.Maybe;
+import io.reactivex.Observable;
+import io.reactivex.Single;
+
 import static androidx.room.OnConflictStrategy.REPLACE;
 
 @Dao
@@ -20,33 +23,27 @@ public interface ContactAttributesDao extends BaseDao<RoomContactAttributes> {
 
     @Override
     @Insert(onConflict = REPLACE)
-    long insert(RoomContactAttributes entity);
+    Single<Long> insert(RoomContactAttributes entity);
 
     @Query("SELECT * FROM contacts WHERE pk_contact_id = :id")
-    LiveData<RoomContactAttributes> getContact(long id);
+    Maybe<RoomContactAttributes> getContact(long id);
-
-    @Query("SELECT * FROM contacts WHERE pk_contact_id = :id")
-    RoomContactAttributes syncGetContact(long id);
 
     @Query("SELECT * FROM contacts WHERE fk_entity_id = :entityId")
-    LiveData<RoomContactAttributes> getContactForEntityId(long entityId);
+    Maybe<RoomContactAttributes> getContactForEntityId(long entityId);
-
-    @Query("SELECT * FROM contacts WHERE fk_entity_id = :entityId")
-    RoomContactAttributes syncGetContactForEntityId(long entityId);
 
     /**
-     * Return a {@link LiveData} wrapping a {@link List} of all {@link RoomContactAttributes RosterEntries}
+     * Return a {@link Observable} wrapping a {@link List} of all {@link RoomContactAttributes RosterEntries}
      * which are currently found in the database.
      *
      * @return
      */
     @Query("SELECT * FROM contacts")
-    LiveData<List<RoomContactAttributes>> getAllContacts();
+    Observable<List<RoomContactAttributes>> getAllContacts();
 
     @Query("SELECT contacts.* FROM contacts JOIN entities " +
             "WHERE contacts.fk_account_id = :accountId AND jid = :jid")
-    RoomContactAttributes getContactByJid(long accountId, EntityBareJid jid);
+    Maybe<RoomContactAttributes> getContactByJid(long accountId, EntityBareJid jid);
 
     @Query("SELECT * FROM contacts WHERE fk_account_id = :accountId")
-    LiveData<List<RoomContactAttributes>> getContactsForAccount(long accountId);
+    Observable<List<RoomContactAttributes>> getContactsForAccount(long accountId);
 }

persistence-room/src/main/java/org/mercury_im/messenger/persistence/room/dao/ContactDao.java

@@ -1,6 +1,5 @@
 package org.mercury_im.messenger.persistence.room.dao;
 
-import androidx.lifecycle.LiveData;
 import androidx.room.Dao;
 import androidx.room.Query;
 import androidx.room.TypeConverters;
@@ -12,6 +11,9 @@ import org.mercury_im.messenger.persistence.room.type_converter.EntityBareJidCon
 
 import java.util.List;
 
+import io.reactivex.Maybe;
+import io.reactivex.Observable;
+
 import static org.mercury_im.messenger.persistence.room.model.RoomContactModel.PREFIX;
 
 @Dao
@@ -25,7 +27,7 @@ public interface ContactDao {
             "entities." + RoomEntityModel.KEY_AVATAR + " AS " + PREFIX + RoomEntityModel.KEY_AVATAR + " " +
             "FROM contacts INNER JOIN entities ON contacts.fk_entity_id = entities.pk_entity_id " +
             "WHERE entities.fk_account_id = :accountId AND entities.jid = :bareJid")
-    LiveData<RoomContactModel> getContactAndEntity(long accountId, EntityBareJid bareJid);
+    Maybe<RoomContactModel> getContactAndEntity(long accountId, EntityBareJid bareJid);
 
     @Query("SELECT contacts.*, " +
             "entities." + RoomEntityModel.KEY_ID + " AS " + PREFIX + RoomEntityModel.KEY_ID + ", " +
@@ -34,7 +36,7 @@ public interface ContactDao {
             "entities." + RoomEntityModel.KEY_AVATAR + " AS " + PREFIX + RoomEntityModel.KEY_AVATAR + " " +
             "FROM contacts INNER JOIN entities ON contacts.fk_entity_id = entities.pk_entity_id " +
             "WHERE entities.fk_account_id = :accountId")
-    LiveData<List<RoomContactModel>> getAllContactAndEntities(long accountId);
+    Observable<List<RoomContactModel>> getAllContactAndEntities(long accountId);
 
     @Query("SELECT contacts.*, " +
             "entities." + RoomEntityModel.KEY_ID + " AS " + PREFIX + RoomEntityModel.KEY_ID + ", " +
@@ -42,5 +44,5 @@ public interface ContactDao {
             "entities." + RoomEntityModel.KEY_JID + " AS " + PREFIX + RoomEntityModel.KEY_JID + ", " +
             "entities." + RoomEntityModel.KEY_AVATAR + " AS " + PREFIX + RoomEntityModel.KEY_AVATAR + " " +
             "FROM contacts INNER JOIN entities ON contacts.fk_entity_id = entities.pk_entity_id")
-    LiveData<List<RoomContactModel>> getAllContactAndEntities();
+    Observable<List<RoomContactModel>> getAllContactAndEntities();
 }

persistence-room/src/main/java/org/mercury_im/messenger/persistence/room/dao/EntityDao.java

@@ -1,6 +1,5 @@
 package org.mercury_im.messenger.persistence.room.dao;
 
-import androidx.lifecycle.LiveData;
 import androidx.room.Dao;
 import androidx.room.Insert;
 import androidx.room.Query;
@@ -10,6 +9,9 @@ import org.jxmpp.jid.EntityBareJid;
 import org.mercury_im.messenger.persistence.room.model.RoomEntityModel;
 import org.mercury_im.messenger.persistence.room.type_converter.EntityBareJidConverter;
 
+import io.reactivex.Maybe;
+import io.reactivex.Single;
+
 import static androidx.room.OnConflictStrategy.REPLACE;
 
 @Dao
@@ -18,18 +20,11 @@ public interface EntityDao extends BaseDao<RoomEntityModel> {
 
     @Override
     @Insert(onConflict = REPLACE)
-    long insert(RoomEntityModel entity);
+    Single<Long> insert(RoomEntityModel entity);
 
     @Query("SELECT * FROM entities WHERE pk_entity_id = :id")
-    LiveData<RoomEntityModel> getEntity(long id);
+    Maybe<RoomEntityModel> getEntity(long id);
-
-    @Query("SELECT * FROM entities WHERE pk_entity_id = :id")
-    RoomEntityModel getEntitySync(long id);
-
 
     @Query("SELECT * FROM entities WHERE fk_account_id = :accountId AND jid = :jid")
-    LiveData<RoomEntityModel> getEntityFor(long accountId, EntityBareJid jid);
+    Maybe<RoomEntityModel> getEntityFor(long accountId, EntityBareJid jid);
-
-    @Query("SELECT * FROM entities WHERE fk_account_id = :accountId AND jid = :jid")
-    RoomEntityModel getEntityForSync(long accountId, EntityBareJid jid);
 }

persistence-room/src/main/java/org/mercury_im/messenger/persistence/room/dao/MessageDao.java

@@ -1,6 +1,5 @@
 package org.mercury_im.messenger.persistence.room.dao;
 
-import androidx.lifecycle.LiveData;
 import androidx.room.Dao;
 import androidx.room.Query;
 import androidx.room.TypeConverters;
@@ -11,17 +10,19 @@ import org.mercury_im.messenger.persistence.room.type_converter.EntityBareJidCon
 
 import java.util.List;
 
+import io.reactivex.Observable;
+
 @Dao
 @TypeConverters(EntityBareJidConverter.class)
 public interface MessageDao extends BaseDao<RoomMessageModel> {
 
     @Query("SELECT * FROM messages WHERE fk_account_id = :accountId ORDER BY send_date ASC")
-    LiveData<List<RoomMessageModel>> getAllMessagesOf(long accountId);
+    Observable<List<RoomMessageModel>> getAllMessagesOf(long accountId);
 
     @Query("SELECT * FROM messages WHERE fk_account_id = :accountId AND `from` = :sender ORDER BY send_date ASC")
-    LiveData<List<RoomMessageModel>> getAllMessagesFrom(long accountId, EntityBareJid sender);
+    Observable<List<RoomMessageModel>> getAllMessagesFrom(long accountId, EntityBareJid sender);
 
     @Query("SELECT * FROM messages WHERE fk_account_id = :accountId AND (`from` = :peer OR `to` = :peer) ORDER BY send_date ASC")
-    LiveData<List<RoomMessageModel>> getAllMessagesInConversation(long accountId, EntityBareJid peer);
+    Observable<List<RoomMessageModel>> getAllMessagesInConversation(long accountId, EntityBareJid peer);
 
 }

persistence-room/src/main/java/org/mercury_im/messenger/persistence/room/repository/IAccountRepository.java

@@ -1,19 +1,18 @@
 package org.mercury_im.messenger.persistence.room.repository;
 
-import android.os.AsyncTask;
-
-import androidx.lifecycle.LiveData;
-import androidx.room.Transaction;
-
 import org.mercury_im.messenger.persistence.repository.AccountRepository;
 import org.mercury_im.messenger.persistence.room.dao.AccountDao;
 import org.mercury_im.messenger.persistence.room.model.RoomAccountModel;
 
 import java.util.List;
-import java.util.concurrent.ExecutionException;
 
 import javax.inject.Inject;
 
+import io.reactivex.Completable;
+import io.reactivex.Maybe;
+import io.reactivex.Observable;
+import io.reactivex.Single;
+
 public class IAccountRepository implements AccountRepository<RoomAccountModel> {
 
     private final AccountDao accountDao;
@@ -24,67 +23,23 @@ public class IAccountRepository implements AccountRepository<RoomAccountModel> {
     }
 
     @Override
-    public LiveData<RoomAccountModel> getAccount(long accountId) {
+    public Maybe<RoomAccountModel> getAccount(long accountId) {
         return accountDao.getAccountById(accountId);
     }
 
     @Override
-    public LiveData<List<RoomAccountModel>> getAllAccountsLive() {
+    public Observable<List<RoomAccountModel>> getAllAccounts() {
-        return accountDao.getAllAccountsLive();
-    }
-
-    @Override
-    public List<RoomAccountModel> getAllAccounts() {
         return accountDao.getAllAccounts();
     }
 
 
     @Override
-    public long insertAccount(RoomAccountModel accountModel) {
+    public Single<Long> insertAccount(RoomAccountModel accountModel) {
-        InsertAsyncTask task = new InsertAsyncTask(accountDao);
+        return accountDao.insert(accountModel);
-        try {
-            return task.execute(accountModel).get();
-        } catch (ExecutionException e) {
-            e.printStackTrace();
-        } catch (InterruptedException e) {
-            e.printStackTrace();
-        }
-        return -1;
     }
 
     @Override
-    public void updateState(long accountId, String state) {
+    public Completable updateState(long accountId, String state) {
-        accountDao.updateConnectionState(accountId, state);
+        return accountDao.updateConnectionState(accountId, state);
-    }
-
-    private static class InsertAsyncTask extends AsyncTask<RoomAccountModel, Void, Long> {
-
-        private final AccountDao accountDao;
-
-        private InsertAsyncTask(AccountDao accountDao) {
-            this.accountDao = accountDao;
-        }
-
-        @Override
-        protected Long doInBackground(RoomAccountModel... accountModels) {
-            for (RoomAccountModel accountModel : accountModels) {
-                return accountDao.insert(accountModel);
-            }
-            return null;
-        }
-    }
-
-    private static class QueryAsyncTask extends AsyncTask<Long, Void, LiveData<RoomAccountModel>> {
-
-        private final AccountDao accountDao;
-
-        private QueryAsyncTask(AccountDao accountDao) {
-            this.accountDao = accountDao;
-        }
-
-        @Override
-        protected LiveData<RoomAccountModel> doInBackground(Long... longs) {
-            return accountDao.getAccountById(longs[0]);
-        }
     }
 }

persistence-room/src/main/java/org/mercury_im/messenger/persistence/room/repository/IChatRepository.java

@@ -1,10 +1,9 @@
 package org.mercury_im.messenger.persistence.room.repository;
 
-import androidx.lifecycle.LiveData;
-
 import org.jxmpp.jid.EntityBareJid;
 import org.mercury_im.messenger.persistence.model.AccountModel;
 import org.mercury_im.messenger.persistence.model.ContactAttributes;
+import org.mercury_im.messenger.persistence.model.ContactModel;
 import org.mercury_im.messenger.persistence.model.EntityModel;
 import org.mercury_im.messenger.persistence.repository.ChatRepository;
 import org.mercury_im.messenger.persistence.room.dao.ChatDao;
@@ -14,6 +13,10 @@ import java.util.List;
 
 import javax.inject.Inject;
 
+import io.reactivex.Completable;
+import io.reactivex.Maybe;
+import io.reactivex.Observable;
+
 public class IChatRepository implements ChatRepository<RoomChatModel> {
 
     private final ChatDao chatDao;
@@ -24,32 +27,37 @@ public class IChatRepository implements ChatRepository<RoomChatModel> {
     }
 
     @Override
-    public LiveData<List<RoomChatModel>> getAllChats() {
+    public Observable<List<RoomChatModel>> getAllChats() {
         return chatDao.getAllChats();
     }
 
     @Override
-    public LiveData<List<RoomChatModel>> getAllChatsOf(AccountModel accountModel) {
+    public Observable<List<RoomChatModel>> getAllChatsOf(AccountModel accountModel) {
         return chatDao.getAllChatsOf(accountModel.getId());
     }
 
     @Override
-    public LiveData<RoomChatModel> getChatWith(EntityModel identity) {
+    public Maybe<RoomChatModel> getChatWith(EntityModel identity) {
         return chatDao.getChatWithIdentity(identity.getId());
     }
 
     @Override
-    public LiveData<RoomChatModel> getChatWith(AccountModel account, EntityBareJid jid) {
+    public Maybe<RoomChatModel> getChatWith(AccountModel account, EntityBareJid jid) {
         return chatDao.getChatWithJid(account.getId(), jid);
     }
 
     @Override
-    public LiveData<RoomChatModel> getChatWith(ContactAttributes contact) {
+    public Maybe<RoomChatModel> getChatWith(ContactAttributes contact) {
         return chatDao.getChatWithContact(contact.getId());
     }
 
     @Override
-    public void closeChat(RoomChatModel chat) {
+    public Maybe<RoomChatModel> getChatWith(ContactModel contact) {
-        chatDao.delete(chat);
+        return getChatWith(contact.getContact());
+    }
+
+    @Override
+    public Completable closeChat(RoomChatModel chat) {
+        return chatDao.delete(chat);
     }
 }

persistence-room/src/main/java/org/mercury_im/messenger/persistence/room/repository/IContactAttributesRepository.java

@@ -1,13 +1,15 @@
 package org.mercury_im.messenger.persistence.room.repository;
 
-import androidx.lifecycle.LiveData;
-
 import org.mercury_im.messenger.persistence.repository.ContactAttributesRepository;
 import org.mercury_im.messenger.persistence.room.dao.ContactAttributesDao;
 import org.mercury_im.messenger.persistence.room.model.RoomContactAttributes;
 
 import java.util.List;
 
+import io.reactivex.Maybe;
+import io.reactivex.Observable;
+import io.reactivex.Single;
+
 public class IContactAttributesRepository implements ContactAttributesRepository<RoomContactAttributes> {
 
     private final ContactAttributesDao contactAttributesDao;
@@ -17,22 +19,22 @@ public class IContactAttributesRepository implements ContactAttributesRepository
     }
 
     @Override
-    public LiveData<List<RoomContactAttributes>> getAllContactAttributes() {
+    public Observable<List<RoomContactAttributes>> getAllContactAttributes() {
         return contactAttributesDao.getAllContacts();
     }
 
     @Override
-    public void updateOrInsertContactAttributes(RoomContactAttributes attributes) {
+    public Single<Long> updateOrInsertContactAttributes(RoomContactAttributes attributes) {
-        contactAttributesDao.insert(attributes);
+        return contactAttributesDao.insert(attributes);
     }
 
     @Override
-    public LiveData<RoomContactAttributes> getContactAttributes(long id) {
+    public Maybe<RoomContactAttributes> getContactAttributes(long id) {
         return contactAttributesDao.getContact(id);
     }
 
     @Override
-    public LiveData<RoomContactAttributes> getContactAttributesForEntity(long entityId) {
+    public Maybe<RoomContactAttributes> getContactAttributesForEntity(long entityId) {
         return contactAttributesDao.getContactForEntityId(entityId);
     }
 

persistence-room/src/main/java/org/mercury_im/messenger/persistence/room/repository/IContactRepository.java

@@ -1,7 +1,5 @@
 package org.mercury_im.messenger.persistence.room.repository;
 
-import androidx.lifecycle.LiveData;
-
 import org.jxmpp.jid.EntityBareJid;
 import org.mercury_im.messenger.persistence.model.EntityModel;
 import org.mercury_im.messenger.persistence.repository.ContactRepository;
@@ -12,6 +10,9 @@ import java.util.List;
 
 import javax.inject.Inject;
 
+import io.reactivex.Maybe;
+import io.reactivex.Observable;
+
 public class IContactRepository implements ContactRepository<RoomContactModel> {
 
     private final ContactDao dao;
@@ -22,22 +23,22 @@ public class IContactRepository implements ContactRepository<RoomContactModel> {
     }
 
     @Override
-    public LiveData<RoomContactModel> getContact(long accountId, EntityBareJid jid) {
+    public Maybe<RoomContactModel> getContact(long accountId, EntityBareJid jid) {
         return dao.getContactAndEntity(accountId, jid);
     }
 
     @Override
-    public LiveData<RoomContactModel> getContactForEntity(EntityModel entityModel) {
+    public Maybe<RoomContactModel> getContactForEntity(EntityModel entityModel) {
         return getContact(entityModel.getAccountId(), entityModel.getJid());
     }
 
     @Override
-    public LiveData<List<RoomContactModel>> getAllContacts(long accountId) {
+    public Observable<List<RoomContactModel>> getAllContactsOfAccount(long accountId) {
         return dao.getAllContactAndEntities(accountId);
     }
 
     @Override
-    public LiveData<List<RoomContactModel>> getAllContacts() {
+    public Observable<List<RoomContactModel>> getAllContacts() {
         return dao.getAllContactAndEntities();
     }
 }

persistence-room/src/main/java/org/mercury_im/messenger/persistence/room/repository/IEntityRepository.java

@@ -1,7 +1,5 @@
 package org.mercury_im.messenger.persistence.room.repository;
 
-import androidx.lifecycle.LiveData;
-
 import org.jxmpp.jid.EntityBareJid;
 import org.mercury_im.messenger.persistence.model.ContactAttributes;
 import org.mercury_im.messenger.persistence.repository.EntityRepository;
@@ -10,6 +8,8 @@ import org.mercury_im.messenger.persistence.room.model.RoomEntityModel;
 
 import javax.inject.Inject;
 
+import io.reactivex.Maybe;
+
 public class IEntityRepository implements EntityRepository<RoomEntityModel> {
 
     private final EntityDao dao;
@@ -20,12 +20,12 @@ public class IEntityRepository implements EntityRepository<RoomEntityModel> {
     }
 
     @Override
-    public <C extends ContactAttributes> LiveData<RoomEntityModel> getEntity(C contact) {
+    public <C extends ContactAttributes> Maybe<RoomEntityModel> getEntity(C contact) {
         return dao.getEntity(contact.getId());
     }
 
     @Override
-    public LiveData<RoomEntityModel> getEntity(long accountId, EntityBareJid jid) {
+    public Maybe<RoomEntityModel> getEntity(long accountId, EntityBareJid jid) {
         return dao.getEntityFor(accountId, jid);
     }
 }

persistence-room/src/main/java/org/mercury_im/messenger/persistence/room/repository/IMessageRepository.java

@@ -1,15 +1,16 @@
 package org.mercury_im.messenger.persistence.room.repository;
 
-import androidx.lifecycle.LiveData;
-
 import org.jxmpp.jid.EntityBareJid;
-import org.jxmpp.jid.EntityFullJid;
 import org.mercury_im.messenger.persistence.repository.MessageRepository;
 import org.mercury_im.messenger.persistence.room.dao.MessageDao;
 import org.mercury_im.messenger.persistence.room.model.RoomMessageModel;
 
 import java.util.List;
 
+import io.reactivex.Maybe;
+import io.reactivex.Observable;
+import io.reactivex.Single;
+
 public class IMessageRepository implements MessageRepository<RoomMessageModel> {
 
     private final MessageDao messageDao;
@@ -19,27 +20,32 @@ public class IMessageRepository implements MessageRepository<RoomMessageModel> {
     }
 
     @Override
-    public long insertMessage(RoomMessageModel message) {
+    public Maybe<RoomMessageModel> getMessage(long accountId, long chatId, long messageId) {
+        return null;
+    }
+
+    @Override
+    public Single<Long> insertMessage(RoomMessageModel message) {
         return messageDao.insert(message);
     }
 
     @Override
-    public LiveData<List<RoomMessageModel>> getAllMessagesOf(long accountId) {
+    public Observable<List<RoomMessageModel>> getAllMessagesOf(long accountId) {
         return messageDao.getAllMessagesOf(accountId);
     }
 
     @Override
-    public LiveData<List<RoomMessageModel>> getAllMessagesFrom(long accountId, EntityBareJid contact) {
+    public Observable<List<RoomMessageModel>> getAllMessagesFrom(long accountId, EntityBareJid contact) {
         return messageDao.getAllMessagesFrom(accountId, contact);
     }
 
     @Override
-    public LiveData<List<RoomMessageModel>> getAllMessagesOfChat(long accountId, EntityBareJid peer) {
+    public Observable<List<RoomMessageModel>> getAllMessagesOfChat(long accountId, EntityBareJid peer) {
         return messageDao.getAllMessagesInConversation(accountId, peer);
     }
 
     @Override
-    public LiveData<List<RoomMessageModel>> findMessageByQuery(String query) {
+    public Observable<List<RoomMessageModel>> findMessageByQuery(String query) {
         return null;
     }
 }

persistence/build.gradle

@@ -1,27 +1,4 @@
-apply plugin: 'com.android.library'
+apply plugin: 'java-library'
-
-android {
-    compileSdkVersion 28
-
-
-    defaultConfig {
-        minSdkVersion 19
-        targetSdkVersion 28
-        versionCode 1
-        versionName "1.0"
-
-        testInstrumentationRunner "androidx.test.runner.AndroidJUnitRunner"
-
-    }
-
-    buildTypes {
-        release {
-            minifyEnabled false
-            proguardFiles getDefaultProguardFile('proguard-android-optimize.txt'), 'proguard-rules.pro'
-        }
-    }
-
-}
 
 dependencies {
 
@@ -31,11 +8,8 @@ dependencies {
         }
     }
 
-    implementation fileTree(dir: 'libs', include: ['*.jar'])
+    // RxJava2
+    implementation "io.reactivex.rxjava2:rxjava:$rxJava2Version"
 
-    implementation 'androidx.appcompat:appcompat:1.0.2'
+    testImplementation "junit:junit:$junitVersion"
-    testImplementation 'junit:junit:4.12'
-    androidTestImplementation 'androidx.test:runner:1.1.1'
-    androidTestImplementation 'androidx.test.espresso:espresso-core:3.1.1'
-    api "androidx.paging:paging-runtime:$pagingVersion"
 }

persistence/src/main/java/org/mercury_im/messenger/persistence/model/EntityModel.java

@@ -1,6 +1,5 @@
 package org.mercury_im.messenger.persistence.model;
 
-import androidx.annotation.NonNull;
 
 import org.jxmpp.jid.EntityBareJid;
 
@@ -17,7 +16,6 @@ public interface EntityModel {
 
     void setId(long id);
 
-    @NonNull
     EntityBareJid getJid();
 
     void setJid(EntityBareJid jid);

persistence/src/main/java/org/mercury_im/messenger/persistence/repository/AccountRepository.java

@@ -1,20 +1,21 @@
 package org.mercury_im.messenger.persistence.repository;
 
-import androidx.lifecycle.LiveData;
-
 import org.mercury_im.messenger.persistence.model.AccountModel;
 
 import java.util.List;
 
+import io.reactivex.Completable;
+import io.reactivex.Maybe;
+import io.reactivex.Observable;
+import io.reactivex.Single;
+
 public interface AccountRepository<E extends AccountModel> {
 
-    LiveData<E> getAccount(long accountId);
+    Maybe<E> getAccount(long accountId);
 
-    LiveData<List<E>> getAllAccountsLive();
+    Observable<List<E>> getAllAccounts();
 
-    List<E> getAllAccounts();
+    Single<Long> insertAccount(E accountModel);
 
-    long insertAccount(E accountModel);
+    Completable updateState(long accountId, String state);
-
-    void updateState(long accountId, String state);
 }

persistence/src/main/java/org/mercury_im/messenger/persistence/repository/ChatRepository.java

@@ -1,26 +1,31 @@
 package org.mercury_im.messenger.persistence.repository;
 
-import androidx.lifecycle.LiveData;
-
 import org.jxmpp.jid.EntityBareJid;
 import org.mercury_im.messenger.persistence.model.AccountModel;
 import org.mercury_im.messenger.persistence.model.ChatModel;
 import org.mercury_im.messenger.persistence.model.ContactAttributes;
+import org.mercury_im.messenger.persistence.model.ContactModel;
 import org.mercury_im.messenger.persistence.model.EntityModel;
 
 import java.util.List;
 
+import io.reactivex.Completable;
+import io.reactivex.Maybe;
+import io.reactivex.Observable;
+
 public interface ChatRepository<E extends ChatModel> {
 
-    LiveData<List<E>> getAllChats();
+    Observable<List<E>> getAllChats();
 
-    LiveData<List<E>> getAllChatsOf(AccountModel account);
+    Observable<List<E>> getAllChatsOf(AccountModel account);
 
-    LiveData<E> getChatWith(AccountModel account, EntityBareJid jid);
+    Maybe<E> getChatWith(AccountModel account, EntityBareJid jid);
 
-    LiveData<E> getChatWith(EntityModel identity);
+    Maybe<E> getChatWith(EntityModel identity);
 
-    LiveData<E> getChatWith(ContactAttributes contact);
+    Maybe<E> getChatWith(ContactAttributes contact);
 
-    void closeChat(E chat);
+    Maybe<E> getChatWith(ContactModel contact);
+
+    Completable closeChat(E chat);
 }

persistence/src/main/java/org/mercury_im/messenger/persistence/repository/ContactAttributesRepository.java

@@ -1,18 +1,20 @@
 package org.mercury_im.messenger.persistence.repository;
 
-import androidx.lifecycle.LiveData;
-
 import org.mercury_im.messenger.persistence.model.ContactAttributes;
 
 import java.util.List;
 
+import io.reactivex.Maybe;
+import io.reactivex.Observable;
+import io.reactivex.Single;
+
 public interface ContactAttributesRepository<E extends ContactAttributes> {
 
-    LiveData<List<E>> getAllContactAttributes();
+    Observable<List<E>> getAllContactAttributes();
 
-    void updateOrInsertContactAttributes(E attributes);
+    Single<Long> updateOrInsertContactAttributes(E attributes);
 
-    LiveData<E> getContactAttributes(long id);
+    Maybe<E> getContactAttributes(long id);
 
-    LiveData<E> getContactAttributesForEntity(long entityId);
+    Maybe<E> getContactAttributesForEntity(long entityId);
 }

persistence/src/main/java/org/mercury_im/messenger/persistence/repository/ContactRepository.java

@@ -1,7 +1,5 @@
 package org.mercury_im.messenger.persistence.repository;
 
-import androidx.lifecycle.LiveData;
-
 import org.jxmpp.jid.EntityBareJid;
 import org.mercury_im.messenger.persistence.model.ContactModel;
 import org.mercury_im.messenger.persistence.model.ContactAttributes;
@@ -9,13 +7,16 @@ import org.mercury_im.messenger.persistence.model.EntityModel;
 
 import java.util.List;
 
+import io.reactivex.Maybe;
+import io.reactivex.Observable;
+
 public interface ContactRepository<CE extends ContactModel<? extends ContactAttributes, ? extends EntityModel>> {
 
-    LiveData<CE> getContact(long accountId, EntityBareJid jid);
+    Maybe<CE> getContact(long accountId, EntityBareJid jid);
 
-    LiveData<CE> getContactForEntity(EntityModel entityModel);
+    Maybe<CE> getContactForEntity(EntityModel entityModel);
 
-    LiveData<List<CE>> getAllContacts(long accountId);
+    Observable<List<CE>> getAllContactsOfAccount(long accountId);
 
-    LiveData<List<CE>> getAllContacts();
+    Observable<List<CE>> getAllContacts();
 }

persistence/src/main/java/org/mercury_im/messenger/persistence/repository/EntityRepository.java

@@ -1,15 +1,15 @@
 package org.mercury_im.messenger.persistence.repository;
 
-import androidx.lifecycle.LiveData;
-
 import org.jxmpp.jid.EntityBareJid;
 import org.mercury_im.messenger.persistence.model.ContactAttributes;
 import org.mercury_im.messenger.persistence.model.EntityModel;
 
+import io.reactivex.Maybe;
+
 public interface EntityRepository<E extends EntityModel> {
 
-    <C extends ContactAttributes> LiveData<E> getEntity(C contact);
+    <C extends ContactAttributes> Maybe<E> getEntity(C contact);
 
-    LiveData<E> getEntity(long accountId, EntityBareJid jid);
+    Maybe<E> getEntity(long accountId, EntityBareJid jid);
 
 }

persistence/src/main/java/org/mercury_im/messenger/persistence/repository/MessageRepository.java

@@ -1,22 +1,25 @@
 package org.mercury_im.messenger.persistence.repository;
 
-import androidx.lifecycle.LiveData;
-
 import org.jxmpp.jid.EntityBareJid;
-import org.jxmpp.jid.EntityFullJid;
 import org.mercury_im.messenger.persistence.model.MessageModel;
 
 import java.util.List;
 
+import io.reactivex.Maybe;
+import io.reactivex.Observable;
+import io.reactivex.Single;
+
 public interface MessageRepository<E extends MessageModel> {
 
-    long insertMessage(E message);
+    Maybe<E> getMessage(long accountId, long chatId, long messageId);
 
-    LiveData<List<E>> getAllMessagesOf(long accountId);
+    Single<Long> insertMessage(E message);
 
-    LiveData<List<E>> getAllMessagesOfChat(long accountId, EntityBareJid peer);
+    Observable<List<E>> getAllMessagesOf(long accountId);
 
-    LiveData<List<E>> getAllMessagesFrom(long accountId, EntityBareJid contact);
+    Observable<List<E>> getAllMessagesOfChat(long accountId, EntityBareJid peer);
 
-    LiveData<List<E>> findMessageByQuery(String query);
+    Observable<List<E>> getAllMessagesFrom(long accountId, EntityBareJid contact);
+
+    Observable<List<E>> findMessageByQuery(String query);
 }

settings.gradle

@@ -1,4 +1,4 @@
 include ':app',
-        ':xmpp_core',
+        ':core',
         ':persistence-room',
         ':persistence'

version.gradle

@@ -70,16 +70,31 @@ ext {
     // Other libraries
 
     // Architecture Components
-    lifecycleVersion = '2.2.0-alpha01'
+    lifecycleVersion = "2.2.0-alpha01"
-    roomVersion = '2.1.0'
+    roomVersion = "2.1.0"
+    roomRxJavaVersion = "2.1.0"
     pagingVersion = "2.1.0"
+    appCompatVersion = "1.1.0-rc01"
+
+    // RxJava2
+    rxJava2Version = "2.2.11"
+    rxAndroidVersion = "2.1.1"
 
     // Dagger 2
-    daggerVersion = '2.23.1'
+    daggerVersion = "2.23.1"
 
     // Android Support Library
     supportLibVersion = "28.0.0"
 
     // Butter Knife
     butterKnifeVersion = "10.1.0"
+
+    // JUnit
+    junitVersion = "4.12"
+    andxTestJunitVersion = "1.1.1"
+
+    // androidx.test:runner
+    andxTestRunnerVersion = "1.2.0"
+    andxTestCoreVersion = "1.2.0"
+    andxTestEspressoVersion = "3.2.0"
 }

xmpp_core/src/main/java/org/mercury_im/messenger/xmpp_core/RosterHandler.java

@@ -1,9 +0,0 @@
-package org.mercury_im.messenger.xmpp_core;
-
-import org.jivesoftware.smack.roster.PresenceEventListener;
-import org.jivesoftware.smack.roster.RosterListener;
-import org.jivesoftware.smack.roster.RosterLoadedListener;
-
-public interface RosterHandler extends RosterListener, RosterLoadedListener, PresenceEventListener {
-
-}