Added EventManager

cms-plugin-framework/CHANGELOG.md

@@ -1,5 +1,8 @@
 # Changelog for org.gcube.application.cms-plugin-framework
 
+## [v1.0.5-SNAPSHOT] - 2023-12-21
+- Added Event Manager
+
 ## [v1.0.4] - 2023-09-06
 - Using parent range version [#25572]
 

cms-plugin-framework/pom.xml

@@ -4,7 +4,7 @@
 	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>cms-plugin-framework</artifactId>
-	<version>1.0.4</version>
+	<version>1.0.5-SNAPSHOT</version>
 
 	<parent>
 		<groupId>org.gcube.application.cms</groupId>

cms-plugin-framework/src/main/java/org/gcube/application/cms/plugins/events/EventListener.java

@@ -0,0 +1,7 @@
+package org.gcube.application.cms.plugins.events;
+
+public interface EventListener<T extends ItemObservable> {
+	
+	public void updated(T observerd);
+
+}

cms-plugin-framework/src/main/java/org/gcube/application/cms/plugins/events/EventManager.java

@@ -0,0 +1,130 @@
+package org.gcube.application.cms.plugins.events;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+
+/**
+ * The Class EventManager.
+ *
+ * @author Francesco Mangiacrapa at ISTI-CNR francesco.mangiacrapa@isti.cnr.it
+ * 
+ *         Dec 11, 2023
+ */
+public class EventManager implements EventManagerInterface<ItemObservable> {
+
+	private HashMap<Event, List<EventListener<ItemObservable>>> listeners = new HashMap<Event, List<EventListener<ItemObservable>>>();
+
+	/**
+	 * The Class Event.
+	 *
+	 * @author Francesco Mangiacrapa at ISTI-CNR francesco.mangiacrapa@isti.cnr.it
+	 * 
+	 *         Nov 29, 2023
+	 */
+	public static enum Event {
+
+		PROJECT_CREATED("PROJECT_CREATED"), 
+		PROJECT_UPDATED("PROJECT_UPDATED"), 
+		PROJECT_DELETED("PROJECT_DELETED"),
+		LIFECYCLE_STEP_PERFORMED("LIFECYCLE_STEP_PERFORMED");
+
+		String name;
+
+		/**
+		 * Instantiates a new event.
+		 *
+		 * @param name the name
+		 */
+		Event(String name) {
+			this.name = name;
+		}
+
+		/**
+		 * Gets the name.
+		 *
+		 * @return the name
+		 */
+		public String getName() {
+			return name;
+		}
+
+	}
+
+	// private instance, so that it can be
+	// accessed by only by getInstance() method
+	private static EventManager instance;
+
+	/**
+	 * Instantiates a new event manager.
+	 */
+	private EventManager() {
+		// private constructor
+	}
+
+	/**
+	 * Gets the single instance of EventManager.
+	 *
+	 * @return single instance of EventManager
+	 */
+	public static EventManager getInstance() {
+		if (instance == null) {
+			// synchronized block to remove overhead
+			synchronized (EventManager.class) {
+				if (instance == null) {
+					// if instance is null, initialize
+					instance = new EventManager();
+				}
+
+			}
+		}
+		return instance;
+	}
+
+	/**
+	 * Subscribe.
+	 *
+	 * @param eventType the event type
+	 * @param listener  the listener
+	 */
+	public void subscribe(Event eventType, EventListener<ItemObservable> listener) {
+		List<EventListener<ItemObservable>> list = listeners.get(eventType);
+		if (list == null)
+			list = new ArrayList<EventListener<ItemObservable>>();
+
+		list.add(listener);
+		listeners.put(eventType, list);
+	}
+
+	/**
+	 * Unsubscribe.
+	 *
+	 * @param eventType the event type
+	 * @param listener  the listener
+	 */
+	public void unsubscribe(Event eventType, EventListener<ItemObservable> listener) {
+		List<EventListener<ItemObservable>> list = listeners.get(eventType);
+		if (list == null)
+			return;
+
+		list.remove(listener);
+		listeners.put(eventType, list);
+	}
+
+	/**
+	 * Notify.
+	 *
+	 * @param eventType the event type
+	 * @param item      the item
+	 */
+	public void notify(Event eventType, ItemObservable item) {
+		for (EventManager.Event event : listeners.keySet()) {
+			if (event.equals(eventType)) {
+				for (EventListener<ItemObservable> eventListner : listeners.get(eventType)) {
+					eventListner.updated(item);
+				}
+			}
+		}
+	}
+
+}

cms-plugin-framework/src/main/java/org/gcube/application/cms/plugins/events/EventManagerInterface.java

@@ -0,0 +1,13 @@
+package org.gcube.application.cms.plugins.events;
+
+import org.gcube.application.cms.plugins.events.EventManager.Event;
+
+public interface EventManagerInterface<T extends ItemObservable> {
+
+	public void subscribe(Event eventType, EventListener<T> listener);
+
+	public void unsubscribe(Event eventType, EventListener<T> listener);
+
+	public void notify(Event eventType, T item);
+
+}

cms-plugin-framework/src/main/java/org/gcube/application/cms/plugins/events/ItemObservable.java

@@ -0,0 +1,7 @@
+package org.gcube.application.cms.plugins.events;
+
+public interface ItemObservable {
+	
+	public String getId();
+
+}

cms-plugin-framework/src/main/java/org/gcube/application/cms/plugins/events/ItemObserved.java

@@ -0,0 +1,31 @@
+package org.gcube.application.cms.plugins.events;
+
+import org.gcube.application.geoportal.common.model.document.Project;
+import org.gcube.application.geoportal.common.model.document.accounting.Context;
+import org.gcube.application.geoportal.common.model.document.accounting.User;
+
+import lombok.AllArgsConstructor;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+import lombok.extern.slf4j.Slf4j;
+
+@Getter
+@Setter
+@NoArgsConstructor
+@AllArgsConstructor
+@Slf4j
+public class ItemObserved<T extends Project> implements ItemObservable {
+	User caller;
+	Context context;
+	T project;
+	EventManager.Event event;
+
+	public String getId() {
+		log.debug("Called getId");
+		if (project == null)
+			return null;
+		return project.getId();
+	}
+
+}