#287: the view model's publish() method no longer needs an UI thread,…

mvvmfx/src/main/java/de/saxsys/mvvmfx/ViewModel.java

@@ -46,9 +46,7 @@
 public interface ViewModel {
 
 	/**
-	 * Publishes a notification to the subscribers of the messageName. This notification will be send to the
-	 * UI-Thread (if the UI-toolkit was bootstrapped). If no UI-Toolkit is available the notification will be directly 
-	 * published. This is typically the case in unit tests. 
+	 * Publishes a notification to the subscribers of the messageName.
 	 * <p>
 	 *     
 	 * This notification mechanism uses the {@link NotificationCenter} internally with the difference that messages send
@@ -64,22 +62,7 @@ public interface ViewModel {
 	 *            to be send
 	 */
 	default void publish(String messageName, Object... payload) {
-		if (Platform.isFxApplicationThread()) {
-			MvvmFX.getNotificationCenter().publish(this, messageName, payload);
-		} else {
-			try {
-				Platform.runLater(() -> MvvmFX.getNotificationCenter().publish(this, messageName, payload));
-			} catch(IllegalStateException e) {
-
-				// If the toolkit isn't initialized yet we will publish the notification directly. 
-				// In most cases this means that we are in a unit test and not JavaFX application is running.
-				if(e.getMessage().equals("Toolkit not initialized")) {
-					MvvmFX.getNotificationCenter().publish(this, messageName, payload);
-				} else {
-					throw e;
-				}
-			}
-		}
+		MvvmFX.getNotificationCenter().publish(this, messageName, payload);
 	}
 
 	/**

mvvmfx/src/main/java/de/saxsys/mvvmfx/utils/notifications/DefaultNotificationCenter.java

@@ -15,17 +15,17 @@
  ******************************************************************************/
 package de.saxsys.mvvmfx.utils.notifications;
 
+import de.saxsys.mvvmfx.ViewModel;
+import javafx.application.Platform;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.HashMap;
-import java.util.Iterator;
 import java.util.List;
 import java.util.stream.Collectors;
 
-import de.saxsys.mvvmfx.ViewModel;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
-
 /**
  * Default implementation of {@link NotificationCenter}.
  * 
@@ -61,12 +61,35 @@ public void unsubscribe(NotificationObserver observer) {
 	public void publish(String messageName, Object... payload) {
 		publish(messageName, payload, globalObservers);
 	}
-
+
+	/**
+	 *  This notification will be send to the UI-Thread (if the UI-toolkit was bootstrapped).
+	 *  If no UI-Toolkit is available the notification will be directly published. This is typically the case in unit tests.
+	 *
+	 * @param viewModel 	the ViewModel
+	 * @param messageName 	the message to sent
+	 * @param payload 		additional arguments to the message
+	 */
 	@Override
 	public void publish(ViewModel viewModel, String messageName, Object[] payload) {
 		ObserverMap observerMap = viewModelObservers.get(viewModel);
 		if (observerMap != null) {
-			publish(messageName, payload, observerMap);
+			if (Platform.isFxApplicationThread()) {
+				publish(messageName, payload, observerMap);
+			} else {
+				try {
+					Platform.runLater(() -> publish(messageName, payload, observerMap));
+				} catch(IllegalStateException e) {
+
+					// If the toolkit isn't initialized yet we will publish the notification directly.
+					// In most cases this means that we are in a unit test and not JavaFX application is running.
+					if(e.getMessage().equals("Toolkit not initialized")) {
+						publish(messageName, payload, observerMap);
+					} else {
+						throw e;
+					}
+				}
+			}
 		}
 	}
 

mvvmfx/src/main/java/de/saxsys/mvvmfx/utils/notifications/NotificationCenterFactory.java

@@ -19,11 +19,16 @@
  * This class is used to get instances of the {@link NotificationCenter} interface.
  */
 public class NotificationCenterFactory {
-
-	private static NotificationCenter singleton = new DefaultNotificationCenter();
-
+
+	private static final NotificationCenter defaultNotificationCenter = new DefaultNotificationCenter();
+	private static NotificationCenter currentNotificationCenter = defaultNotificationCenter;
+
 	public static NotificationCenter getNotificationCenter() {
-		return singleton;
+		return currentNotificationCenter;
 	}
-
+
+    public static void setNotificationCenter(final NotificationCenter notificationCenter) {
+        currentNotificationCenter = notificationCenter;
+    }
+
 }

mvvmfx/src/test/java/de/saxsys/mvvmfx/utils/notifications/DefaultNotificationCenterTest.java

@@ -16,11 +16,22 @@
 
 package de.saxsys.mvvmfx.utils.notifications;
 
+import de.saxsys.mvvmfx.ViewModel;
+import de.saxsys.mvvmfx.testingutils.jfxrunner.JfxRunner;
+import javafx.application.Platform;
 import org.junit.Before;
-import org.junit.Ignore;
 import org.junit.Test;
+import org.junit.runner.RunWith;
 import org.mockito.Mockito;
 
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.TimeoutException;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@RunWith(JfxRunner.class)
 public class DefaultNotificationCenterTest {
 
 	private static final String TEST_NOTIFICATION = "test_notification";
@@ -38,7 +49,7 @@ public void init() {
 		observer1 = Mockito.mock(DummyNotificationObserver.class);
 		observer2 = Mockito.mock(DummyNotificationObserver.class);
 		observer3 = Mockito.mock(DummyNotificationObserver.class);
-		defaultCenter = Mockito.spy(new DefaultNotificationCenter());
+		defaultCenter = new DefaultNotificationCenter();
 	}
 
 	@Test
@@ -108,6 +119,34 @@ public void unsubscribeObserverThatWasSubscribedMultipleTimes() {
 		defaultCenter.publish(TEST_NOTIFICATION);
 		Mockito.verify(observer1, Mockito.never()).receivedNotification(TEST_NOTIFICATION);
 	}
+
+	@Test
+	public void observerForViewModelIsCalledFromUiThread() throws InterruptedException, ExecutionException, TimeoutException {
+		// Check that there is a UI-Thread available. This JUnit-Test isn't running on the UI-Thread but there needs to
+		// be a UI-Thread available in the background.
+		CompletableFuture<Void> uiThreadIsAvailable = new CompletableFuture<>();
+		Platform.runLater(() -> uiThreadIsAvailable.complete(null));  // This would throw an IllegalStateException if no
+		// UI-Thread is available.
+		uiThreadIsAvailable.get(1l, TimeUnit.SECONDS);
+
+		CompletableFuture<Boolean> future = new CompletableFuture<>();
+
+		// The test doesn't run on the FX thread.
+		assertThat(Platform.isFxApplicationThread()).isFalse();
+
+		final ViewModel viewModel = Mockito.mock(ViewModel.class);
+		defaultCenter.subscribe(viewModel, TEST_NOTIFICATION, (key, payload) -> {
+			// the notification is executed on the FX thread.
+			future.complete(Platform.isFxApplicationThread());
+		});
+
+		// view model publish() should be executed in the UI-thread
+		defaultCenter.publish(viewModel, TEST_NOTIFICATION, new Object[]{});
+
+		final Boolean wasCalledOnUiThread = future.get(1l, TimeUnit.SECONDS);
+
+		assertThat(wasCalledOnUiThread).isTrue();
+	}
 
 	private class DummyNotificationObserver implements NotificationObserver {
 		@Override

mvvmfx/src/test/java/de/saxsys/mvvmfx/utils/notifications/ViewModelTest.java

@@ -5,7 +5,6 @@
 import de.saxsys.mvvmfx.testingutils.jfxrunner.JfxRunner;
 import javafx.application.Platform;
 import org.junit.Before;
-import org.junit.Ignore;
 import org.junit.Test;
 import org.junit.runner.RunWith;
 import org.mockito.Mockito;
@@ -15,8 +14,6 @@
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
 
-import static org.assertj.core.api.Assertions.assertThat;
-
 @RunWith(JfxRunner.class)
 public class ViewModelTest {
 
@@ -36,37 +33,7 @@ public void init() {
 		viewModel = new ViewModel() {
 		};
 	}
-
-	@Test
-	public void observerIsCalledFromUiThread() throws InterruptedException, ExecutionException, TimeoutException {
-		// Check that there is a UI-Thread available. This JUnit-Test isn't running on the UI-Thread but there needs to
-		// be a UI-Thread available in the background.
-		CompletableFuture<Void> uiThreadIsAvailable = new CompletableFuture<>();
-		Platform.runLater(() -> uiThreadIsAvailable.complete(null));  // This would throw an IllegalStateException if no
-																		// UI-Thread is available.
-		uiThreadIsAvailable.get(1l, TimeUnit.SECONDS);
-
-
-
-		CompletableFuture<Boolean> future = new CompletableFuture<>();
-
-		// The test doesn't run on the FX thread.
-		assertThat(Platform.isFxApplicationThread()).isFalse();
-
-		viewModel.subscribe(TEST_NOTIFICATION, (key, payload) -> {
-			// the notification is executed on the FX thread.
-				future.complete(Platform.isFxApplicationThread());
-			});
-
-		viewModel.publish(TEST_NOTIFICATION);
-
-
-		final Boolean wasCalledOnUiThread = future.get(1l, TimeUnit.SECONDS);
-
-		assertThat(wasCalledOnUiThread).isTrue();
-	}
-
-
+
 	@Test
 	public void observerFromOutsideDoesNotReceiveNotifications() {
 		MvvmFX.getNotificationCenter().subscribe(TEST_NOTIFICATION, observer1);