poco/Foundation/include/Poco/Observer.h
Aleksandar Fabijanic 88be66972a
AsyncObserver (#4444)
* feat(AsyncObserver): Improve NotificationCenter speed and usability #4414

* fix(Notification): add missing header

* feat(Any): add checkers for holding nullptr #4447

* feat(NotificationCenter): g++ build and refactoring #4414

* fix(Observer): compile errors on some compilers #4414

* fix(NotificationCenter): compile errors #4414

* chore(ParallelSocketAcceptor): remove unnecessary include and using from header

* feat(AsyncNotificationCenter): add #4414

* test(AsyncNotificationCenter): add mixed observer types to the test #4414

* fix(AsyncNotificationCenter): hangs on program exit #4414

* fix(dev): friend not honored, temporarily make private members public

* fix(AsyncNotificationCenter); remove default #4414
2024-02-16 09:34:19 +01:00

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2.6 KiB
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Executable File

//
// Observer.h
//
// Library: Foundation
// Package: Notifications
// Module: NotificationCenter
//
// Definition of the Observer class template.
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier: BSL-1.0
//
#ifndef Foundation_Observer_INCLUDED
#define Foundation_Observer_INCLUDED
#include "Poco/Foundation.h"
#include "Poco/AbstractObserver.h"
#include "Poco/Mutex.h"
namespace Poco {
template <class C, class N>
class Observer: public AbstractObserver
/// This template class implements an adapter that sits between
/// a NotificationCenter and an object receiving notifications
/// from it. It is quite similar in concept to the
/// RunnableAdapter, but provides some NotificationCenter
/// specific additional methods.
/// See the NotificationCenter class for information on how
/// to use this template class.
///
/// Instead of the Observer class template, you might want to
/// use the NObserver class template, which uses an AutoPtr to
/// pass the Notification to the callback function, thus freeing
/// you from memory management issues.
{
public:
typedef void (C::*Callback)(N*);
Observer(C& object, Callback method):
_pObject(&object),
_method(method)
{
}
Observer(const Observer& observer):
AbstractObserver(observer),
_pObject(observer._pObject),
_method(observer._method)
{
}
~Observer()
{
}
Observer& operator = (const Observer& observer)
{
if (&observer != this)
{
_pObject = observer._pObject;
_method = observer._method;
}
return *this;
}
void notify(Notification* pNf) const
{
Poco::Mutex::ScopedLock lock(_mutex);
if (_pObject)
{
pNf->duplicate();
(_pObject->*_method)(static_cast<N*>(pNf));
}
}
bool equals(const AbstractObserver& abstractObserver) const
{
const Observer* pObs = dynamic_cast<const Observer*>(&abstractObserver);
return pObs && pObs->_pObject == _pObject && pObs->_method == _method;
}
[[deprecated("use `bool accepts(const Notification::Ptr&)` instead")]]
bool accepts(Notification* pNf, const char* pName) const
{
return (!pName || pNf->name() == pName) && (dynamic_cast<N*>(pNf) != nullptr);
}
bool accepts(const Notification::Ptr& pNf) const
{
return (pNf.cast<N>() != nullptr);
}
AbstractObserver* clone() const
{
return new Observer(*this);
}
void disable()
{
Poco::Mutex::ScopedLock lock(_mutex);
_pObject = 0;
}
private:
Observer();
C* _pObject;
Callback _method;
mutable Poco::Mutex _mutex;
};
} // namespace Poco
#endif // Foundation_Observer_INCLUDED