Changeset 1c291d for src/CodePatterns/Observer/Channels.hpp

Timestamp:

Mar 18, 2013, 6:29:41 PM (13 years ago)

Author:

Frederik Heber <heber@…>

Children:

3f30cc

Parents:

b9273a

git-author:

Frederik Heber <heber@…> (03/18/13 18:22:47)

git-committer:

Frederik Heber <heber@…> (03/18/13 18:29:41)

Message:

Channels and Notifications pass on subjectKilled().

• if we only sign on to a single notification channel, we miss on subjectKilled() completely. Hence, we have to chance of properly signing off again or, at least, to know that we must not anymore.
• Hence, Observable's dstor now calls subjectKilled() on its Channels which passes the call on to all its Notifications that in turn use the subjectKilled() slot of their targets along with the passed-through Observable instance.
• also added observerLog verbosity when signing on/off to channels.
• explained this in header documentation of Observable, Channels, and Notification.
• TESTFIX: ObserverUnitTest did not properly signOff() before deleting instances in relayNotificationTest().

File:

• src/CodePatterns/Observer/Channels.hpp (modified) (3 diffs)

src/CodePatterns/Observer/Channels.hpp

@@ -18 +18 @@
 #include "CodePatterns/Observer/defs.hpp"
 
+class Observable;
+class Relay;
+
 /** Channels aggregate all possible Notifications of an Observable.
  *
@@ -23 +26 @@
  * visible to the outside only.
  *
+ * \note Channels::subjectKilled() needs to be called by owning Observable.
+ * It is passed on to Notification such that Observer that have only signed
+ * on to single channel still know when their observable has died.
  */
 class Channels {
@@ -38 +44 @@
 
 private:
+  //! grant Observable access to notifyAll() and subjectKilled()
+  friend class Observable;
+  //!> grant Relay access to notifyAll()
+  friend class Relay;
+
+  /** Informs channel subscribers about imminent dstor call.
+   *
+   * This is meant to be called from Observable only.
+   * Channels and Notifications are strictly attached to an Observable. Hence,
+   * it makes no sense to inform them on their own. Especially, neither has
+   * any knowledge on the publisher.
+   *
+   * \param *publisher Observable about to be destroyed
+   */
+  void subjectKilled(Observable * const publisher);
+
+private:
   typedef std::map< size_t, Notification_ptr> NotificationTypetoRefMap;