/*
* Copyright (C) 2013 Google Inc. All Rights Reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
* EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE COMPUTER, INC. OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
* OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
#ifndef LifecycleContext_h
#define LifecycleContext_h
#include "platform/LifecycleNotifier.h"
#include "platform/LifecycleObserver.h"
#include "wtf/HashSet.h"
#include "wtf/OwnPtr.h"
#include "wtf/PassOwnPtr.h"
namespace WebCore {
template <typename T>
class LifecycleContext {
public:
typedef LifecycleNotifier<T> Notifier;
typedef LifecycleObserver<T> Observer;
LifecycleContext() { }
virtual ~LifecycleContext() { }
virtual bool isContextThread() const { return true; }
// Called from the constructor of observers.
void wasObservedBy(Observer*);
// Called from the destructor of observers.
void wasUnobservedBy(Observer*);
protected:
Notifier& lifecycleNotifier();
private:
PassOwnPtr<Notifier> createLifecycleNotifier();
OwnPtr<Notifier> m_lifecycleNotifier;
};
template<typename T>
inline void LifecycleContext<T>::wasObservedBy(typename LifecycleContext<T>::Observer* observer)
{
ASSERT(isContextThread());
lifecycleNotifier().addObserver(observer);
}
template<typename T>
inline void LifecycleContext<T>::wasUnobservedBy(typename LifecycleContext<T>::Observer* observer)
{
ASSERT(isContextThread());
lifecycleNotifier().removeObserver(observer);
}
template<typename T>
inline typename LifecycleContext<T>::Notifier& LifecycleContext<T>::lifecycleNotifier()
{
if (!m_lifecycleNotifier)
m_lifecycleNotifier = static_cast<T*>(this)->createLifecycleNotifier();
return *m_lifecycleNotifier;
}
template<typename T>
inline PassOwnPtr<typename LifecycleContext<T>::Notifier> LifecycleContext<T>::createLifecycleNotifier()
{
return LifecycleContext<T>::Notifier::create(static_cast<T*>(this));
}
} // namespace WebCore
#endif // LifecycleContext_h