Common: Eventbuilder received build method and EventReader received toString + hashCode + equals method (OpenEMS#2408)

* EventBuilder received a Build method for new Events and
* EventReader received toString, hashCode and equals method

This commit is one of many prepare PRs / commits for a bigger PR:
SumStateAlert OpenEMS#2260
By Seperating the big OpenEMS#2260 into smaller commits we would like to make the review easier.

Co-authored-by: Kai Jeschek <99220919+da-Kai@users.noreply.github.com>

Author: DerStoecki

io.openems.common/src/io/openems/common/event/EventBuilder.java

@@ -36,7 +36,7 @@ public static EventBuilder from(EventAdmin eventAdmin, String eventTopic) {
 	 * @throws SecurityException If the caller does not have
 	 *                           TopicPermission[topic,PUBLISH] for the topic
 	 *                           specified in the event.
-	 * @see org.osgi.service.event.EventAdmin#postEvent(Event)
+	 * @see EventAdmin#postEvent(Event)
 	 */
 	public static void post(EventAdmin eventAdmin, String eventTopic) {
 		eventAdmin.postEvent(new Event(eventTopic, Map.of()));
@@ -48,10 +48,10 @@ public static void post(EventAdmin eventAdmin, String eventTopic) {
 	 * @throws SecurityException If the caller does not have
 	 *                           TopicPermission[topic,PUBLISH] for the topic
 	 *                           specified in the event.
-	 * @see org.osgi.service.event.EventAdmin#postEvent(Event)
+	 * @see EventAdmin#postEvent(Event)
 	 */
 	public void post() throws SecurityException {
-		this.eventAdmin.postEvent(new Event(this.eventTopic, this.eventArgs));
+		this.eventAdmin.postEvent(this.build());
 	}
 
 	/**
@@ -62,7 +62,7 @@ public void post() throws SecurityException {
 	 * @throws SecurityException If the caller does not have
 	 *                           TopicPermission[topic,PUBLISH] for the topic
 	 *                           specified in the event.
-	 * @see org.osgi.service.event.EventAdmin#sendEvent(Event)
+	 * @see EventAdmin#sendEvent(Event)
 	 */
 	public static void send(EventAdmin eventAdmin, String eventTopic) {
 		eventAdmin.sendEvent(new Event(eventTopic, Map.of()));
@@ -74,10 +74,19 @@ public static void send(EventAdmin eventAdmin, String eventTopic) {
 	 * @throws SecurityException If the caller does not have
 	 *                           TopicPermission[topic,PUBLISH] for the topic
 	 *                           specified in the event.
-	 * @see org.osgi.service.event.EventAdmin#sendEvent(Event)
+	 * @see EventAdmin#sendEvent(Event)
 	 */
 	public void send() throws SecurityException {
-		this.eventAdmin.sendEvent(new Event(this.eventTopic, this.eventArgs));
+		this.eventAdmin.sendEvent(this.build());
+	}
+
+	/**
+	 * Build event and return it.
+	 *
+	 * @return built {@link Event}
+	 */
+	public Event build() {
+		return new Event(this.eventTopic, this.eventArgs);
 	}
 
 	/**

io.openems.common/src/io/openems/common/event/EventReader.java

@@ -2,6 +2,7 @@
 
 import java.time.ZoneId;
 import java.time.ZonedDateTime;
+import java.util.Objects;
 
 import org.osgi.service.event.Event;
 
@@ -116,4 +117,31 @@ public ZonedDateTime getZonedDateTime(String propertyId, String timeZone) {
 		return this.getZonedDateTime(propertyId, ZoneId.of(timeZone));
 	}
 
+	@Override
+	public String toString() {
+		StringBuilder asString = new StringBuilder("EventReader{Event={Topic=");
+		asString.append(this.getTopic()).append(", Params={");
+		for (var property : this.event.getPropertyNames()) {
+			if (property.equals("event.topics")) {
+				break;
+			}
+			asString.append(property).append("=").append(this.event.getProperty(property)).append(", ");
+		}
+		asString.delete(asString.length() - 2, asString.length());
+		asString.append("}}}");
+		return asString.toString();
+	}
+
+	@Override
+	public int hashCode() {
+		return Objects.hash(this.event);
+	}
+
+	@Override
+	public boolean equals(Object obj) {
+		return this == obj //
+				|| obj instanceof EventReader other //
+						&& Objects.equals(this.event, other.event);
+	}
+
 }