ClickHouse/base/poco/Foundation/include/Poco/NotificationStrategy.h

106 lines
3.0 KiB
C++

//
// NotificationStrategy.h
//
// Library: Foundation
// Package: Events
// Module: NotificationStrategy
//
// Definition of the NotificationStrategy interface.
//
// Copyright (c) 2006-2011, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier: BSL-1.0
//
#ifndef Foundation_NotificationStrategy_INCLUDED
#define Foundation_NotificationStrategy_INCLUDED
#include "Poco/Foundation.h"
namespace Poco
{
template <class TArgs, class TDelegate>
class NotificationStrategy
/// The interface that all notification strategies must implement.
///
/// Note: Event is based on policy-driven design, so every strategy implementation
/// must provide all the methods from this interface (otherwise: compile errors)
/// but does not need to inherit from NotificationStrategy.
{
public:
typedef TDelegate * DelegateHandle;
NotificationStrategy() { }
virtual ~NotificationStrategy() { }
virtual void notify(const void * sender, TArgs & arguments) = 0;
/// Sends a notification to all registered delegates.
virtual DelegateHandle add(const TDelegate & delegate) = 0;
/// Adds a delegate to the strategy.
virtual void remove(const TDelegate & delegate) = 0;
/// Removes a delegate from the strategy, if found.
/// Does nothing if the delegate has not been added.
virtual void remove(DelegateHandle delegateHandle) = 0;
/// Removes a delegate from the strategy, if found.
/// Does nothing if the delegate has not been added.
virtual void clear() = 0;
/// Removes all delegates from the strategy.
virtual bool empty() const = 0;
/// Returns false if the strategy contains at least one delegate.
};
template <class TDelegate>
class NotificationStrategy<void, TDelegate>
/// The interface that all notification strategies must implement.
///
/// Note: Event is based on policy-driven design, so every strategy implementation
/// must provide all the methods from this interface (otherwise: compile errors)
/// but does not need to inherit from NotificationStrategy.
{
public:
typedef TDelegate * DelegateHandle;
NotificationStrategy() { }
virtual ~NotificationStrategy() { }
virtual void notify(const void * sender) = 0;
/// Sends a notification to all registered delegates.
virtual DelegateHandle add(const TDelegate & delegate) = 0;
/// Adds a delegate to the strategy.
virtual void remove(const TDelegate & delegate) = 0;
/// Removes a delegate from the strategy, if found.
/// Does nothing if the delegate has not been added.
virtual void remove(DelegateHandle delegateHandle) = 0;
/// Removes a delegate from the strategy, if found.
/// Does nothing if the delegate has not been added.
virtual void clear() = 0;
/// Removes all delegates from the strategy.
virtual bool empty() const = 0;
/// Returns false if the strategy contains at least one delegate.
};
} // namespace Poco
#endif // Foundation_NotificationStrategy_INCLUDED