Changeset bc1fbf for molecuilder/src/Patterns

Timestamp:

Feb 3, 2010, 4:31:45 PM (16 years ago)

Author:

Tillmann Crueger <crueger@…>

Children:

8501eb

Parents:

2e8296

Message:

Changed Observer to use RAII-style for locking changes.

Location:

molecuilder/src/Patterns

Files:

• Observer.cpp (modified) (1 diff)
• Observer.hpp (modified) (3 diffs)

molecuilder/src/Patterns/Observer.cpp

@@ -51 +51 @@
     depth.erase(publisher);
   }
+}
+
+Observable::_Observable_protector::_Observable_protector(Observable *_protege) :
+  protege(_protege)
+{
+  start_observer_internal(protege);
+}
+
+Observable::_Observable_protector::~_Observable_protector()
+{
+  finish_observer_internal(protege);
 }
 

molecuilder/src/Patterns/Observer.hpp

@@ -16 +16 @@
  *
  * Observers register themselves with the observables to be notified when something changes.
- * In the Observable code that changes attributes should be wrapped in
- * START_OBSERVER ... END_OBSERVER blocks. If other methods are called that also contain
- * Observation blocks from there, these functions wont trigger notifications. Only the end
- * of the final observation block triggers the update of Observers.
- *
- * Returning from observed code should be done using the RETURN_OBSERVER() macro. This way the Observer mechanism
- * is notified that the method is left.
+ * In the Observable code that changes attributes should be started with OBSERVE;. This macro
+ * locks the observer mechanism while changes are done. At the end of the scope in which the
+ * macro was placed the lock is released. When the last lock is released all changes are
+ * propagated to the observers.
  *
  * Each observerable can have sub-observables. When one of these sub-observables changes and
@@ -62 +59 @@
   /**
    * Internal method.
-   * Do not call directly. Use START_OBSERVER macro instead
+   * Do not call directly. Use OBSERVE macro instead
    */
   static void start_observer_internal(Observable *publisher);
   /**
    * Internal method.
-   * Do not call directly. Use FINISH_OBSERVER macro instead
+   * Do not call directly. Use OBSERVE macro instead
    */
   static void finish_observer_internal(Observable *publisher);
@@ -76 +73 @@
   static std::map<Observable*,callees_t*> callTable;
   static std::set<Observable*> busyObservables;
+
+  // Structure for RAII-Style notification
+protected:
+  class _Observable_protector {
+  public:
+    _Observable_protector(Observable *);
+    ~_Observable_protector();
+  private:
+    Observable *protege;
+  };
 };
 
 
-
+#define OBSERVE Observable::_Observable_protector _scope_obs_protector(this)
 #define START_OBSERVER Observable::start_observer_internal(this);do{do{}while(0)
 #define FINISH_OBSERVER }while(0);Observable::finish_observer_internal(this)