Changeset b324a3 for src

Timestamp:

Sep 5, 2013, 2:14:06 PM (12 years ago)

Author:

Frederik Heber <heber@…>

Children:

44f368

Parents:

37d941

git-author:

Frederik Heber <heber@…> (09/05/13 14:09:44)

git-committer:

Frederik Heber <heber@…> (09/05/13 14:14:06)

Message:

Added Graveyard for to-be-destroyed Observables.

• also added Zombie class that wraps an Observable.
• Notification and Observable have new function getNumberOfObservers().
• added unit test for Graveyard.

Location:

src

Files:

• CodePatterns/Observer/Graveyard.hpp (added)
• CodePatterns/Observer/Notification.hpp (modified) (1 diff)
• CodePatterns/Observer/Observable.hpp (modified) (4 diffs)
• CodePatterns/Observer/Zombie.hpp (added)
• Observer/Graveyard.cpp (added)
• Observer/Makefile.am (modified) (3 diffs)
• Observer/Observable.cpp (modified) (5 diffs)
• Observer/unittests/GraveyardUnitTest.cpp (added)
• Observer/unittests/GraveyardUnitTest.hpp (added)
• Observer/unittests/Makefile.am (modified) (3 diffs)

src/CodePatterns/Observer/Notification.hpp

@@ -65 +65 @@
   void subjectKilled(Observable * const publisher);
 
+  /** Getter for the number of Observer for this notification (channel).
+   *
+   * \return number of added observers
+   */
+  size_t getNumberOfObservers() const
+  { return targets.size(); }
+
 private:
   typedef std::set<Observer*> targets_t;

src/CodePatterns/Observer/Observable.hpp

@@ -17 +17 @@
 #include <set>
 #include <string>
+#include <boost/function.hpp>
 
 #include "CodePatterns/Range.hpp"
 #include "CodePatterns/Observer/defs.hpp"
 #include "CodePatterns/Observer/Observer.hpp"
+
+class Graveyard;
 
 /**
@@ -34 +37 @@
  * we call Channels::subjectKilled() to let Observers that have only signed
  * on to single channel still know when their observable has died.
+ *
+ * Note that one may allow an Observable to live some over-time by using
+ * the Graveyard. This allows any Observer to still access the instance
+ * in order to properly sign off. It is destroyed when no Observer is left.
  */
 class Observable : public Observer {
@@ -93 +100 @@
   Notification_ptr getChannel(size_t no) const;
 
+  size_t getNumberOfObservers() const;
+
 protected:
   virtual void update(Observable *publisher);
@@ -126 +135 @@
   static std::set<Observable*> busyObservables;
 
+private:
+  friend class Zombie;
+  friend class Graveyard;
+
+  typedef boost::function<void (const Observable*)> graveyard_informer_t;
+
+  //!> bound function to call when Observer are signing off
+  graveyard_informer_t &graveyard_informer;
+
+  //!> default informer that does nothing
+  static graveyard_informer_t noop_informer;
+
+  /** Sets the bound function for over-time life-time management.
+   *
+   * \param _graveyard Graveyard to inform of leaving Observers
+   */
+  void setGraveyardInformer(graveyard_informer_t &_graveyard_informer)
+  {
+    graveyard_informer = _graveyard_informer;
+  }
+
   //! @cond
   // Structure for RAII-Style notification

src/Observer/Makefile.am

@@ -10 +10 @@
 OBSERVERSOURCE = \
         Channels.cpp \
+        Graveyard.cpp \
         Notification.cpp \
         Observable.cpp \
@@ -23 +24 @@
         $(top_srcdir)/src/CodePatterns/Observer/Channels.hpp \
         $(top_srcdir)/src/CodePatterns/Observer/defs.hpp \
+        $(top_srcdir)/src/CodePatterns/Observer/Graveyard.hpp \
         $(top_srcdir)/src/CodePatterns/Observer/Notification.hpp \
         $(top_srcdir)/src/CodePatterns/Observer/Observable.hpp \
@@ -30 +32 @@
         $(top_srcdir)/src/CodePatterns/Observer/ObservedIterator.hpp \
         $(top_srcdir)/src/CodePatterns/Observer/ObservedContainer_impl.hpp \
-        $(top_srcdir)/src/CodePatterns/Observer/Relay.hpp
+        $(top_srcdir)/src/CodePatterns/Observer/Relay.hpp \
+        $(top_srcdir)/src/CodePatterns/Observer/Zombie.hpp
 
 OBSERVERDEBUGHEADER =

src/Observer/Observable.cpp

@@ -27 +27 @@
 #include "CodePatterns/Observer/Notification.hpp"
 
+//!> This function does nothing with the given Observable
+void NoOp_informer(const Observable *)
+{}
+
+Observable::graveyard_informer_t Observable::noop_informer(&NoOp_informer);
 
 // All infrastructure for the observer-pattern is bundled at a central place
@@ -271 +276 @@
     callTable.erase(const_cast<Observable *>(this));
   }
+  graveyard_informer(this);
 }
 
@@ -293 +299 @@
 #endif
   notification->removeObserver(target);
+  graveyard_informer(this);
 }
 
@@ -311 +318 @@
 }
 
+size_t Observable::getNumberOfObservers() const
+{
+  size_t ObserverCount = 0;
+  {
+    std::map<Observable*,callees_t>::const_iterator callTableiter =
+        callTable.find(const_cast<Observable *>(this));
+    // if not present, then we have zero observers
+    if (callTableiter != callTable.end())
+      ObserverCount += callTableiter->second.size();
+  }
+  {
+    const ChannelMap::const_iterator iter =
+        NotificationChannels.find(const_cast<Observable * const>(this));
+    // if not present, then we have zero observers
+    if (iter != NotificationChannels.end())
+      for (Channels::NotificationTypetoRefMap::const_iterator channeliter = iter->second->ChannelMap.begin();
+          channeliter != iter->second->ChannelMap.end();
+          ++channeliter)
+        ObserverCount += (channeliter->second)->getNumberOfObservers();
+  }
+  return ObserverCount;
+}
+
 /** Handles sub-observables that just got killed
  *  when an sub-observerable dies we usually don't need to do anything
@@ -321 +351 @@
  */
 Observable::Observable(std::string name) :
-  Observer(Observer::BaseConstructor())
+  Observer(Observer::BaseConstructor()),
+  graveyard_informer(noop_informer)
 {
 #ifdef LOG_OBSERVER

src/Observer/unittests/Makefile.am

@@ -5 +5 @@
 
 TESTS += \
+        GraveyardUnitTest \
         ObservedContainerUnitTest \
         ObserverUnitTest
 
 TESTSOURCES += \
+        ../Observer/unittests/GraveyardUnitTest.cpp \
         ../Observer/unittests/ObserverUnitTest.cpp \
         ../Observer/unittests/ObservedContainerUnitTest.cpp \
@@ -14 +16 @@
 
 TESTHEADERS += \
+        ../Observer/unittests/GraveyardUnitTest.hpp \
         ../Observer/unittests/ObserverUnitTest.hpp \
         ../Observer/unittests/ObservedContainerUnitTest.hpp
@@ -38 +41 @@
         ../Helpers/libCodePatterns-Helpers-debug.la
 
+GraveyardUnitTest_SOURCES = UnitTestMain.cpp \
+        ../Observer/unittests/GraveyardUnitTest.cpp \
+        ../Observer/unittests/GraveyardUnitTest.hpp \
+        ../Observer/unittests/stubs/ObserverStub.cpp \
+        ../Observer/unittests/stubs/ObserverStub.hpp
+nodist_GraveyardUnitTest_SOURCES = \
+        $(top_srcdir)/src/CodePatterns/Observer/Channels.hpp \
+        $(top_srcdir)/src/CodePatterns/Observer/defs.hpp \
+        $(top_srcdir)/src/CodePatterns/Observer/Notification.hpp \
+        $(top_srcdir)/src/CodePatterns/Observer/Observer.hpp \
+        $(top_srcdir)/src/CodePatterns/Observer/ObserverLog.hpp \
+        $(top_srcdir)/src/CodePatterns/Observer/ObserverContainer.hpp \
+        $(top_srcdir)/src/CodePatterns/Observer/ObserverContainer_impl.hpp \
+        $(top_srcdir)/src/CodePatterns/Observer/ObserverIterator.hpp
+GraveyardUnitTest_LDADD = \
+        ../Observer/libCodePatterns-Observer-debug.la \
+        ../Helpers/libCodePatterns-Helpers-debug.la
+
 ObservedContainerUnitTest_SOURCES = UnitTestMain.cpp \
         ../Observer/unittests/ObservedContainerUnitTest.cpp \