+ /**
+ * Checks if another Activity matches the general information of another.
+ * @param $activityB
+ * @return bool
+ */
+ public function isSimilarTo($activityB) {
+ return [$this->key, $this->entity_type, $this->entity_id] === [$activityB->key, $activityB->entity_type, $activityB->entity_id];
+ }
+