ClickHouse/base/poco/XML/include/Poco/DOM/EventDispatcher.h

//
// EventDispatcher.h
//
// Library: XML
// Package: DOM
// Module:  DOMEvents
//
// Definition of the EventDispatcher class.
//
// Copyright (c) 2004-2006, Applied Informatics Software Engineering GmbH.
// and Contributors.
//
// SPDX-License-Identifier:	BSL-1.0
//


#ifndef DOM_EventDispatcher_INCLUDED
#define DOM_EventDispatcher_INCLUDED


#include <list>
#include "Poco/XML/XML.h"
#include "Poco/XML/XMLString.h"


namespace Poco
{
namespace XML
{


    class Event;
    class EventListener;


    class XML_API EventDispatcher
    /// This helper class manages event listener subscriptions
    /// and event dispatching for AbstractNode.
    ///
    /// The EventListener list is managed in such a way that
    /// event listeners can be added and removed even
    /// from within an EventListener, while events are being
    /// dispatched.
    {
    public:
        EventDispatcher();
        /// Creates the EventDispatcher.

        ~EventDispatcher();
        /// Destroys the EventDispatcher.

        void addEventListener(const XMLString & type, EventListener * listener, bool useCapture);
        /// Adds an EventListener to the internal list.

        void removeEventListener(const XMLString & type, EventListener * listener, bool useCapture);
        /// Removes an EventListener from the internal list.
        ///
        /// If a dispatch is currently in progress, the list
        /// entry is only marked for deletion.
        /// If no dispatch is currently in progress, all EventListeners
        /// marked for deletion are removed from the list.

        void dispatchEvent(Event * evt);
        /// Dispatches the event.
        ///
        /// Also removes all EventListeners marked for deletion from the
        /// event dispatcher list.

        void captureEvent(Event * evt);
        /// Dispatches the event in its capturing phase.
        ///
        /// Also removes all EventListeners marked for deletion from the
        /// event dispatcher list.

        void bubbleEvent(Event * evt);
        /// Dispatches the event in its bubbling phase.
        ///
        /// Also removes all EventListeners marked for deletion from the
        /// event dispatcher list.

    private:
        struct EventListenerItem
        {
            XMLString type;
            EventListener * pListener;
            bool useCapture;
        };

        typedef std::list<EventListenerItem> EventListenerList;

        int _inDispatch;
        EventListenerList _listeners;
    };


}
} // namespace Poco::XML


#endif // DOM_EventDispatcher_INCLUDED