add javadoc

Signed-off-by: Michael Hirsch <michael.hirsch@bosch-si.com>

hawkbit-repository/hawkbit-repository-jpa/src/main/java/org/eclipse/hawkbit/repository/jpa/model/EntityPropertyChangeListener.java

@@ -13,7 +13,8 @@ import org.eclipse.persistence.descriptors.DescriptorEvent;
 import org.eclipse.persistence.descriptors.DescriptorEventAdapter;
 
 /**
- * Listens to change in property values of an entity.
+ * Listens to change in property values of an entity and calls the corresponding
+ * {@link EventAwareEntity}.
  *
  */
 public class EntityPropertyChangeListener extends DescriptorEventAdapter {

hawkbit-repository/hawkbit-repository-jpa/src/main/java/org/eclipse/hawkbit/repository/jpa/model/EventAwareEntity.java

@@ -10,22 +10,29 @@ package org.eclipse.hawkbit.repository.jpa.model;
 
 import org.eclipse.persistence.descriptors.DescriptorEvent;
 
+/**
+ * Interfaces which can be implemented by entities to be called when the entity
+ * should fire an event because the entity has been created, updated or deleted.
+ */
 public interface EventAwareEntity {
 
     /**
      * Fired for the Entity creation.
+     * 
      * @param descriptorEvent
      */
     void fireCreateEvent(DescriptorEvent descriptorEvent);
 
     /**
      * Fired for the Entity updation.
+     * 
      * @param descriptorEvent
      */
     void fireUpdateEvent(DescriptorEvent descriptorEvent);
 
     /**
      * Fired for the Entity deletion.
+     * 
      * @param descriptorEvent
      */
     void fireDeleteEvent(DescriptorEvent descriptorEvent);