Changeset 74e0f7 for src/Patterns/Observer.hpp

Timestamp:

Sep 1, 2011, 11:07:47 AM (14 years ago)

Author:

Frederik Heber <heber@…>

Children:

9e776f

Parents:

451f17

git-author:

Frederik Heber <heber@…> (09/01/11 11:02:49)

git-committer:

Frederik Heber <heber@…> (09/01/11 11:07:47)

Message:

Extended Observables by NotificationChannels member variable.

• new class Channels that aggregates Notifications.
• NOTIFY now just takes a channel number.
• may or may not be instantiated for a given Observable.
• Observable just needs to add enum of all desired channels and addChannel on each of these.
• ObserverUnitTest has been adapted.

File:

• src/Patterns/Observer.hpp (modified) (6 diffs)

src/Patterns/Observer.hpp

@@ -40 +40 @@
 #endif
 
+class Channels;
+class Notification;
 class Observable;
-class Notification;
 
 // Pointers to notifications are used for unique identification
@@ -145 +146 @@
   virtual bool isBlocked();
 
+  Notification_ptr getChannel(size_t no) const;
+
 protected:
   virtual void update(Observable *publisher);
@@ -164 +167 @@
 
   static void enque_notification_internal(Observable *publisher, Notification_ptr notification);
+
+  Channels *NotificationChannels;
 
 private:
@@ -192 +197 @@
 };
 
+/** Notifications are sort of new channels of an Observable.
+ * Via the NOTIFY() macro updates can be transmitted in a specific channel.
+ * Observers can subscribe to Notification in much the same way as they can to
+ * the Observable itself. Usually, Notifications
+ */
 class Notification {
   friend class Observable;
+  friend class Channels;
 public:
   Notification(Observable *_owner);
+  Notification(Observable *_owner, size_t _channelno);
   virtual ~Notification();
+
+  size_t getChannelNo() const { return channelno; }
 protected:
 
@@ -206 +220 @@
   Observable * const owner;
   std::set<Observer*> targets;
+  size_t channelno;
+};
+
+/** Channels aggregate all possible Notifications of an Observable.
+ *
+ * Usually, one implements an enumeration of the channel number which is
+ * visible to the outside only.
+ *
+ */
+class Channels {
+public:
+  Channels(Observable *_owner);
+  virtual ~Channels();
+
+  void addChannel(size_t no);
+
+  Notification_ptr getChannel(size_t no) const;
+  size_t getType(Notification_ptr channel) const;
+
+protected:
+  void removeChannel(size_t no);
+
+private:
+  Observable * const owner;
+
+  typedef std::map< size_t, Notification_ptr> NotificationTypetoRefMap;
+
+  NotificationTypetoRefMap ChannelMap;
 };
 
@@ -245 +287 @@
 #define PASTE_HELPER(a,b) a ## b
 #define OBSERVE Observable::_Observable_protector PASTE(_scope_obs_protector_,__LINE__)(this)
-#define NOTIFY(notification) do{Observable::enque_notification_internal(this,notification);}while(0)
+#define NOTIFY(channelno) do{Observable::enque_notification_internal(this,NotificationChannels->getChannel(channelno));}while(0)
 #define LOCK_OBSERVABLE(observable) Observable::_Observable_protector PASTE(_scope_obs_protector_,__LINE__)(&(observable))