/*

* Copyright (c) 2004-2005 Nokia Corporation and/or its subsidiary(-ies). 

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of the License "Symbian Foundation License v1.0" to Symbian Foundation members and "Symbian Foundation End User License Agreement v1.0" to non-members

* which accompanies this distribution, and is available

* at the URL "http://www.symbianfoundation.org/legal/licencesv10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description:       Interface class describing class that may contains user

 *                 data aded to node

 *

*/

#ifndef XMLENGINE_USERDATA_H_INCLUDED

#define XMLENGINE_USERDATA_H_INCLUDED

#include <e32def.h>

/**

 * MXmlEngUserData is an abstract base class (interface) for user data that can be

 * stored in the DOM tree. Applications that wish to store user data in the 

 * DOM tree must wrap the user data in a class that implemens this interface.

 *

 * @lib XmlEngineDOM.lib

 * @since S60 v3.1

 */

class MXmlEngUserData {

public:

    /**

     * Free memory that is allocated and do other case specific cleanup.

     *

     * @since S60 v3.1

     */

    virtual void Destroy() = 0;

    /**

     * Make a copy of the the object. Note that if reference counting is used or

     * the same pointer can be safely copied to other places the implementation

     * of this method may just return a pointer to self.

     *

     * Copying user data when copying nodes has not been implemented

     * so this method is for future use (though there's no harm in implementing 

     * it, of course).

     *

     * @since S60 v3.1

     * @return Pointer to a copy of this object.

     */

    virtual MXmlEngUserData* CloneL() = 0;

    /**

     * Get id of the object. It is up to user-data provider what the result is.

     * Such a "user data identification" may be in use if several types of

     * MXmlEngUserData objects are used.

     *

     * @since S60 v3.1

     * @return Pointer that somehow identifies the type of MXmlEngUserData (NULL by default)

     */

    virtual void* ID() {return NULL;}

};

#endif /* XMLENGINE_USERDATA_H_INCLUDED*/