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 * 
 * Licensed to the Apache Software Foundation (ASF) under one
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 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
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#ifndef __FILTER_CONFIG_CACHEUPDATELISTENER_HXX_
#define __FILTER_CONFIG_CACHEUPDATELISTENER_HXX_

//_______________________________________________
// includes

#include "filtercache.hxx"
#include <com/sun/star/lang/XMultiServiceFactory.hpp>
#include <com/sun/star/lang/XEventListener.hpp>
#include <com/sun/star/util/XChangesListener.hpp>
#include <salhelper/singletonref.hxx>
#include <cppuhelper/implbase1.hxx>

//_______________________________________________
// namespace

namespace filter{
    namespace config{

//_______________________________________________
// definitions

//_______________________________________________

/** @short      implements a listener, which will update the
                global filter cache, if the underlying configuration
                wa changed by other processes.
 */
class CacheUpdateListener : public BaseLock // must be the first one to guarantee right initialized mutex member!
                          , public ::cppu::WeakImplHelper1< css::util::XChangesListener >
{
    //-------------------------------------------
    // member

    private:

        /** @short  reference to an uno service manager, which can be used
                    to create own needed services. */
        css::uno::Reference< css::lang::XMultiServiceFactory > m_xSMGR;

        /** @short  reference to the singleton(!) filter cache implementation,
                    which should be updated by this thread. */
        ::salhelper::SingletonRef< FilterCache > m_rCache;

        /** @short  holds the configuration access, where we listen alive. */
        css::uno::Reference< css::uno::XInterface > m_xConfig;

        /** @short  every instance of this update listener listen on
                    a special sub set of the filter configuration.
                    So it should know, which type of configuration entry
                    it must put into the filter cache, if the configuration notifys changes ... */
        FilterCache::EItemType m_eConfigType;

    //-------------------------------------------
    // native interface

    public:

        //---------------------------------------
        // ctor/dtor

        /** @short  initialize new instance of this class.

            @descr  Listening won't be started here. It can be done
                    by calling startListening() on this instance.

            @see    startListening()

            @param  xSMGR
                    reference to a service manager, which can be used to create
                    own needed uno services.

            @param  xConfigAccess
                    the configuration access, where this instance should listen for changes.

            @param  eConfigType
                    specify the type of configuration.
         */
        CacheUpdateListener(const css::uno::Reference< css::lang::XMultiServiceFactory >& xSMGR        ,
                            const css::uno::Reference< css::uno::XInterface >&            xConfigAccess,
                                  FilterCache::EItemType                                  eConfigType  );

        //---------------------------------------

        /** @short  standard dtor.
         */
        virtual ~CacheUpdateListener();

        //---------------------------------------

        /** @short  starts listening.
         */
        virtual void startListening();

        //---------------------------------------

        /** @short  stop listening.
         */
        virtual void stopListening();

    //-------------------------------------------
    // uno interface

    public:

        //---------------------------------------
        // XChangesListener

        virtual void SAL_CALL changesOccurred(const css::util::ChangesEvent& aEvent)
            throw(css::uno::RuntimeException);

        //---------------------------------------
        // lang.XEventListener
        virtual void SAL_CALL disposing(const css::lang::EventObject& aEvent)
            throw(css::uno::RuntimeException);
};

    } // namespace config
} // namespace filter

#endif // __FILTER_CONFIG_CACHEUPDATELISTENER_HXX_