00001 #ifndef __WATCHBLE_H_INCLUDED__ 00002 #define __WATCHBLE_H_INCLUDED__ 00003 00004 // $Id$ 00005 00006 //********************************************************************** 00007 // * 00008 // Description: Watchable object base class. * 00009 // * 00010 // Author: Chris White (whitecf@bcs.org.uk) * 00011 // * 00012 // Copyright (C) 2003 Monitor Computing Services Ltd. * 00013 // * 00014 // This program is free software; you can redistribute it and/or * 00015 // modify it under the terms of the GNU General Public License * 00016 // as published by the Free Software Foundation; either version 2 * 00017 // of the License, or any later version. * 00018 // * 00019 // This program is distributed in the hope that it will be useful, * 00020 // but WITHOUT ANY WARRANTY; without even the implied warranty of * 00021 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * 00022 // GNU General Public License for more details. * 00023 // * 00024 // You should have received a copy of the GNU General Public * 00025 // License (http://www.gnu.org/copyleft/gpl.html) along with this * 00026 // program; if not, write to: * 00027 // The Free Software Foundation Inc., * 00028 // 59 Temple Place - Suite 330, * 00029 // Boston, MA 02111-1307, * 00030 // USA. * 00031 // * 00032 //********************************************************************** 00033 // * 00034 // Notes: * 00035 // * 00036 //********************************************************************** 00037 00038 00039 namespace Monitor { 00040 namespace Utility { 00041 00042 // Forward declerations within namespace 00043 class CallbackBase; 00044 class CallbackList; 00045 00046 00047 00051 class Watchable 00052 { 00053 public: 00057 Watchable(); 00058 00062 virtual ~Watchable(); 00063 00064 00072 const CallbackBase& 00073 addWatch(const CallbackBase& newWatch) const; 00074 00080 void 00081 removeWatch(const CallbackBase& oldWatch) const; 00082 00088 void 00089 removeWatcher(const void* watcher) const; 00090 00096 virtual void 00097 updated(const void* updateData = 0) const; 00098 00102 void 00103 freeze() const; 00104 00108 void 00109 thaw() const; 00110 00111 00112 private: 00116 mutable CallbackList* watchList; 00117 00121 mutable int frozen; 00122 }; 00123 00124 }; // namespace Utility 00125 }; // namespace Monitor 00126 00127 #endif // __WATCHBLE_H_INCLUDED__ 00128