Auto update Calendar component asynchronously

pom.xml

@@ -50,6 +50,10 @@
 			<groupId>com.vaadin</groupId>
 			<artifactId>vaadin-spring-boot-starter</artifactId>
 		</dependency>
+		<dependency>
+			<groupId>com.vaadin</groupId>
+			<artifactId>vaadin-push</artifactId>
+		</dependency>
 		<dependency>
 			<groupId>org.hibernate</groupId>
 			<artifactId>hibernate-core</artifactId>
@@ -112,7 +116,6 @@
 		<dependency>
 			<groupId>com.h2database</groupId>
 			<artifactId>h2</artifactId>
-			<version>1.4.197</version>
 			<scope>test</scope>
 		</dependency>
 	</dependencies>

src/main/java/de/kreth/vaadin/clubhelper/vaadinclubhelper/dao/EventBusiness.java

@@ -11,16 +11,21 @@ import java.util.List;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Component;
 
 import com.vaadin.server.VaadinRequest;
 
 import de.kreth.clubhelperbackend.google.calendar.CalendarAdapter;
 import de.kreth.vaadin.clubhelper.vaadinclubhelper.data.ClubEvent;
 
+@Component
 public class EventBusiness {
 
 	private final Logger log = LoggerFactory.getLogger(getClass());
-	private final List<ClubEvent> cache = new ArrayList<>();
+	
+	@Autowired
+	ClubEventDao dao;
 
 	public List<ClubEvent> loadEvents(VaadinRequest request) {
 		return loadEvents(request, false);
@@ -28,17 +33,21 @@ public class EventBusiness {
 
 	public synchronized List<ClubEvent> loadEvents(VaadinRequest request,
 			boolean forceRefresh) {
-		if (cache.isEmpty() == false && forceRefresh == false) {
+		
-			log.trace("Returning cached events: {}", cache);
+		if (forceRefresh == false) {
-			return Collections.unmodifiableList(cache);
+			List<ClubEvent> list = dao.list();
+			log.trace("Returning events from database: {}");
+			return list;
 		}
 
 		log.debug(
-				"Loading events from Google Calendar, cache size was: {}, forceRefresh={}",
+				"Loading events from Google Calendar, forceRefresh={}",
-				cache.size(), forceRefresh);
+				forceRefresh);
-		cache.clear();
 
 		BufferedWriter out = null;
+
+		List<ClubEvent> list = new ArrayList<>();
+		
 		try {
 			if (forceRefresh) {
 				File f = new File("google_events.json");
@@ -58,7 +67,7 @@ public class EventBusiness {
 				}
 
 				if ("cancelled".equals(ev.getStatus()) == false) {
-					cache.add(ClubEvent.parse(ev));
+					list.add(ClubEvent.parse(ev));
 				} else {
 					log.debug("Cancelled: {}", ev.getSummary());
 				}
@@ -75,6 +84,6 @@ public class EventBusiness {
 				log.error("Error writing File", e);
 			}
 		}
-		return Collections.unmodifiableList(cache);
+		return Collections.unmodifiableList(list);
 	}
 }

src/main/java/de/kreth/vaadin/clubhelper/vaadinclubhelper/data/ClubEvent.java

@@ -91,9 +91,9 @@ public class ClubEvent extends BasicItem {
 
 	@Override
 	public String toString() {
-		return "ClubEvent [id=" + id + ", iCalUID=" + iCalUID + ", location="
+		return "ClubEvent [id=" + id + ", getCaption()=" + getCaption() + ", iCalUID=" + iCalUID + ", location="
 				+ location + ", organizerDisplayName=" + organizerDisplayName
-				+ ", getCaption()=" + getCaption() + ", getDescription()="
+				+ ", getDescription()="
 				+ getDescription() + ", getEnd()=" + getEnd() + ", getStart()="
 				+ getStart() + ", isAllDay()=" + isAllDay() + "]";
 	}

src/main/java/de/kreth/vaadin/clubhelper/vaadinclubhelper/ui/MainUi.java

@@ -9,8 +9,10 @@ import org.slf4j.LoggerFactory;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.vaadin.addon.calendar.ui.CalendarComponentEvents;
 
+import com.vaadin.annotations.Push;
 import com.vaadin.annotations.Theme;
 import com.vaadin.server.VaadinRequest;
+import com.vaadin.shared.communication.PushMode;
 import com.vaadin.spring.annotation.SpringUI;
 import com.vaadin.ui.HorizontalLayout;
 import com.vaadin.ui.UI;
@@ -25,6 +27,7 @@ import de.kreth.vaadin.clubhelper.vaadinclubhelper.ui.components.PersonGrid;
 
 @Theme("vaadin-clubhelpertheme")
 @SpringUI
+@Push(value=PushMode.MANUAL)
 public class MainUi extends UI {
 
 	private static final long serialVersionUID = 7581634188909841919L;
@@ -36,6 +39,9 @@ public class MainUi extends UI {
 	@Autowired
 	GroupDao groupDao;
 	
+	@Autowired
+	EventBusiness eventBusiness;
+
 	private PersonGrid personGrid;
 
 	private CalendarComponent calendar;
@@ -67,10 +73,14 @@ public class MainUi extends UI {
 		ExecutorService exec = Executors.newSingleThreadExecutor();
 		exec.execute(() -> {
 
-			EventBusiness business = new EventBusiness();
+			final List<ClubEvent> events = eventBusiness.loadEvents(request);
-			List<ClubEvent> events = business.loadEvents(request);
 			LOGGER.info("Loaded events: {}", events);
+			final UI ui = calendar.getUI();
+			ui.access(() -> {
 				calendar.setItems(events);
+				ui.push();
+			});
+			
 		});
 		exec.shutdown();
 	}

src/main/java/de/kreth/vaadin/clubhelper/vaadinclubhelper/ui/components/CalendarComponent.java

@@ -83,6 +83,7 @@ public class CalendarComponent extends CustomComponent {
 
 	public void setItems(Collection<ClubEvent> items) {
 		dataProvider.setItems(items);
+		calendar.markAsDirty();
 	}
 
 	class ClubEventProvider extends BasicItemProvider<ClubEvent> {