Observer.h

/***********************************************************************
 * The rDock program was developed from 1998 - 2006 by the software team
 * at RiboTargets (subsequently Vernalis (R&D) Ltd).
 * In 2006, the software was licensed to the University of York for
 * maintenance and distribution.
 * In 2012, Vernalis and the University of York agreed to release the
 * program as Open Source software.
 * This version is licensed under GNU-LGPL version 3.0 with support from
 * the University of Barcelona.
 * http://rdock.sourceforge.net/
 ***********************************************************************/
 
// Abstract Observer class for Subject-Observer design pattern, see Subject.h
// Design considerations:
// Subclasses should override the Update and Deleted methods, which are invoked
// by the subject when the subject changes state or is about to be deleted,
// respectively.
// Observer subclasses also need to store a pointer to the concrete subject
// subclass (e.g. WorkSpace), either via Register and Unregister methods or
// via the constructor, so that subject subclass methods can be called to get
// details of the change in state. No pointer to the base subject object is
// stored in the base observer object.
 
#ifndef _RBTOBSERVER_H_
#define _RBTOBSERVER_H_
 
#include <vector>
 
namespace rxdock {
 
class Subject;
 
class Observer {
public:
  // Constructors/destructors
  virtual ~Observer(); // Default destructor
 
  // Public methods
  // PURE VIRTUAL - DERIVED CLASSES MUST OVERRIDE
  // Notify observer that subject has changed
  virtual void Update(Subject *theChangedSubject) = 0;
  // Notify observer that subject is about to be deleted
  virtual void Deleted(Subject *theDeletedSubject) = 0;
 
protected:
  // Protected methods
  Observer();
 
private:
  // Private methods
  Observer(const Observer &);            // Copy constructor disabled by default
  Observer &operator=(const Observer &); // Copy assignment disabled by default
 
protected:
  // Protected data
 
private:
  // Private data
};
 
// Useful typedefs
typedef std::vector<Observer *> ObserverList;
typedef ObserverList::iterator ObserverListIter;
typedef ObserverList::const_iterator ObserverListConstIter;
 
} // namespace rxdock
 
#endif //_RBTOBSERVER_H_