sd/source/ui/slidesorter/cache/SlsRequestQueue.hxx

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  19
  20 #ifndef INCLUDED_SD_SOURCE_UI_SLIDESORTER_CACHE_SLSREQUESTQUEUE_HXX
  21 #define INCLUDED_SD_SOURCE_UI_SLIDESORTER_CACHE_SLSREQUESTQUEUE_HXX
  22
  23 #include "SlsRequestPriorityClass.hxx"
  24 #include "cache/SlsCacheContext.hxx"
  25 #include "taskpane/SlideSorterCacheDisplay.hxx"
  26 #include <drawdoc.hxx>
  27 #include <osl/mutex.hxx>
  28 #include <svx/sdrpageuser.hxx>
  29
  30 namespace sd { namespace slidesorter { namespace cache {
  31
  32 class RequestData;
  33
  34 /** The request queue stores requests that are described by the RequestData
  35     sorted according to priority class and then priority.
  36 */
  37 class RequestQueue : public sdr::PageUser
  38 {
  39 public:
  40     RequestQueue (const SharedCacheContext& rpCacheContext);
  41     virtual ~RequestQueue();
  42
  43     /** Insert a request with highest or lowest priority in its priority
  44         class.  When the request is already present then it is first
  45         removed.  This effect is then a re-prioritization.
  46         @param aKey
  47             The request.
  48         @param eRequestClass
  49             The priority class in which to insert the request with highest
  50             or lowest priority.
  51         @param bInsertWithHighestPriority
  52             When this flag is <TRUE/> the request is inserted with highes
  53             priority in its class.  When <FALSE/> the request is inserted
  54             with lowest priority.
  55     */
  56     void AddRequest (
  57         CacheKey aKey,
  58         RequestPriorityClass eRequestClass,
  59         bool bInsertWithHighestPriority = false);
  60
  61     /** Remove the specified request from the queue.
  62         @param aKey
  63             It is OK when the specified request is not a member of the
  64             queue.
  65         @return
  66             Returns <TRUE/> when the request has been successfully been
  67             removed from the queue.  Otherwise, e.g. because the request was
  68             not a member of the queue, <FALSE/> is returned.
  69     */
  70     bool RemoveRequest (CacheKey aKey);
  71
  72     /** Change the priority class of the specified request.
  73     */
  74     void ChangeClass (
  75         CacheKey aKey,
  76         RequestPriorityClass eNewRequestClass);
  77
  78     /** Get the request with the highest priority int the highest priority class.
  79     */
  80     CacheKey GetFront();
  81
  82     // For debugging.
  83     RequestPriorityClass GetFrontPriorityClass();
  84
  85     /** Really a synonym for RemoveRequest(GetFront());
  86     */
  87     void PopFront();
  88
  89     /** Returns <TRUE/> when there is no element in the queue.
  90     */
  91     bool IsEmpty();
  92
  93     /** Remove all requests from the queue.  This resets the minimum and
  94         maximum priorities to their default values.
  95     */
  96     void Clear();
  97
  98     /** Return the mutex that guards the access to the priority queue.
  99     */
 100     ::osl::Mutex& GetMutex() { return maMutex;}
 101
 102     /** Ensure we don't hand out a page deleted before anyone got a
 103         chance to process it
 104     */
 105     virtual void PageInDestruction(const SdrPage& rPage) SAL_OVERRIDE;
 106
 107 private:
 108     ::osl::Mutex maMutex;
 109     class Container;
 110     ::boost::scoped_ptr<Container> mpRequestQueue;
 111     SharedCacheContext mpCacheContext;
 112
 113     /** A lower bound of the lowest priority of all elements in the queues.
 114         The start value is 0.  It is assigned and then decreased every time
 115         when an element is inserted or marked as the request with lowest
 116         priority.
 117     */
 118     int mnMinimumPriority;
 119     /** An upper bound of the highest priority of all elements in the queues.
 120         The start value is 1.  It is assigned and then increased every time
 121         when an element is inserted or marked as the request with highest
 122         priority.
 123     */
 124     int mnMaximumPriority;
 125 };
 126
 127 } } } // end of namespace ::sd::slidesorter::cache
 128
 129 #endif
 130
 131 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */