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 * 
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * 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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#if !defined INCLUDED_COMPHELPER_ACCESSIBLEEVENTBUFFER_HXX
#define INCLUDED_COMPHELPER_ACCESSIBLEEVENTBUFFER_HXX

#include "com/sun/star/uno/Reference.hxx"
#include "com/sun/star/uno/Sequence.hxx"

#include <vector>

namespace com { namespace sun { namespace star { namespace uno {
    class XInterface;
} } } }
namespace com { namespace sun { namespace star {
    namespace accessibility { struct AccessibleEventObject; }
} } }

namespace comphelper {

/**
   A buffer for AccessibleEventObjects about to be sent to
   XAccessibleEventListeners.

   This buffer records pairs of AccessibleEventObjects and sequences of
   XAccessibleEventListeners.  At a time when it is safe to do so (e.g., when
   no critical mutexes are held), all events can be notified at once.

   This class is not thread-safe in itself, but it is thread-compatible (i.e.,
   all multi-threaded uses of instances of this class have to ensure proper
   mutual exclusion).
 */
class AccessibleEventBuffer
{
public:
    /**
       Create an initially empty buffer.

       Internally uses ::std::vector and thus may throw exceptions thrown by
       operations on ::std::vector, especially ::std::bad_alloc.
     */
    AccessibleEventBuffer();

    /**
       Create a buffer with a copy of another buffer.

       The events from the other buffer are copied, not shared.

       Internally uses ::std::vector and thus may throw exceptions thrown by
       operations on ::std::vector, especially ::std::bad_alloc.
     */
    AccessibleEventBuffer(AccessibleEventBuffer const & rOther);

    /**
       Destroy the buffer.

       If the buffer contains any events that have not yet been sent, those
       events are lost.

       Does not throw any exceptions.
     */
    ~AccessibleEventBuffer();

    /**
       Copy another buffer into this buffer.

       If this buffer contained any events that had not yet been sent, those
       events are lost.  The events from the other buffer are copied, not
       shared.

       Internally uses ::std::vector and thus may throw exceptions thrown by
       operations on ::std::vector, especially ::std::bad_alloc.
     */
    AccessibleEventBuffer operator =(AccessibleEventBuffer const & rOther);

    /**
       Add an event to the buffer.

       Internally uses ::std::vector and thus may throw exceptions thrown by
       operations on ::std::vector, especially ::std::bad_alloc.
     */
    void addEvent(
        ::com::sun::star::accessibility::AccessibleEventObject const &
        rEvent,
        ::com::sun::star::uno::Sequence< ::com::sun::star::uno::Reference<
        ::com::sun::star::uno::XInterface > > const & rListeners);

    /**
       Sends all the events accumulated in the buffer.

       If sending any of the events to a specific XAccessibleListener fails with
       a RuntimeException, that exception is ignored and the method carries on
       with the rest of the notifications.

       After sending all events, the buffer is cleared.
     */
    void sendEvents() const;

private:
    struct Entry;

    typedef ::std::vector< Entry > Entries;

    Entries m_aEntries;
};

}

#endif // INCLUDED_COMPHELPER_ACCESSIBLEEVENTBUFFER_HXX