include/svl/IndexedStyleSheets.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  */
   9
  10 #ifndef INCLUDED_SVL_INDEXEDSTYLESHEETS_HXX
  11 #define INCLUDED_SVL_INDEXEDSTYLESHEETS_HXX
  12
  13 #include <sal/types.h>
  14
  15 #include <rsc/rscsfx.hxx>
  16 #include <rtl/ustring.hxx>
  17 #include <rtl/ref.hxx>
  18
  19 #include <svl/svldllapi.h>
  20
  21 #include <unordered_map>
  22 #include <vector>
  23
  24 class SfxStyleSheetBase;
  25
  26 namespace svl {
  27
  28 /** Function object to check whether a style sheet a fulfills specific criteria.
  29  * Derive from this class and override the Check() method.
  30  */
  31 struct StyleSheetPredicate {
  32     virtual bool Check(const SfxStyleSheetBase& styleSheet) = 0;
  33     virtual ~StyleSheetPredicate() {;}
  34 };
  35
  36 /** Function object for cleanup-Strategy for IndexedSfxStyleSheets::Clear().
  37  * Derive from it and do what is necessary to dispose of a style sheet in Dispose().
  38  */
  39 struct StyleSheetDisposer {
  40     virtual void Dispose(rtl::Reference<SfxStyleSheetBase> styleSheet) = 0;
  41     virtual ~StyleSheetDisposer() {;}
  42 };
  43
  44 /** Function object to apply a method on all style sheets.
  45  * Derive from it and do whatever you want to with the style sheet in the DoIt() method.
  46  */
  47 struct StyleSheetCallback {
  48     virtual void DoIt(const SfxStyleSheetBase& styleSheet) = 0;
  49     virtual ~StyleSheetCallback() {;}
  50 };
  51
  52 /** This class holds SfxStyleSheets and allows for access via an id and a name.
  53  *
  54  * @warning
  55  * The identification of style sheets happens by their name. If the name of a sheet changes,
  56  * it will not be found again! Please call Reindex() after changing a style sheet's name.
  57  *
  58  * @internal
  59  * This class was implemented to mitigate solve #fdo 30770.
  60  * The issue describes an Excel file which takes several hours to open.
  61  * An analysis revealed that the time is spent searching for style sheets with linear scans in an array.
  62  * This class implements access to the style sheets via their name in (usually) constant time.
  63  *
  64  * The return type for most methods is a vector of unsigned integers which denote the position
  65  * of the style sheets in the vector, and not of pointers to style sheets.
  66  * You will need a non-const StyleSheetPool to obtain the actual style sheets.
  67  *
  68  *
  69  * Index-based access is required in several code portions. Hence we have to store the style sheets
  70  * in a vector as well as in a map.
  71  */
  72 class SVL_DLLPUBLIC IndexedStyleSheets SAL_FINAL
  73 {
  74 public:
  75     IndexedStyleSheets();
  76
  77     /** Destructor.
  78      *
  79      * @internal
  80      * Is explicit because it has to know how to dispose of SfxStyleSheetBase objects.
  81      */
  82     ~IndexedStyleSheets();
  83
  84     /** Adds a style sheet.
  85      *
  86      * If the style sheet is already contained, this call has no effect.
  87      */
  88     void
  89     AddStyleSheet(rtl::Reference< SfxStyleSheetBase > style);
  90
  91     /** Removes a style sheet. */
  92     bool
  93     RemoveStyleSheet(rtl::Reference< SfxStyleSheetBase > style);
  94
  95     /** Check whether a specified style sheet is stored. */
  96     bool
  97     HasStyleSheet(rtl::Reference< SfxStyleSheetBase > style) const;
  98
  99     /** Obtain the number of style sheets which are held */
 100     unsigned
 101     GetNumberOfStyleSheets() const;
 102
 103     /** Obtain the number of style sheets for which a certain condition holds */
 104     unsigned
 105     GetNumberOfStyleSheetsWithPredicate(StyleSheetPredicate& predicate) const;
 106
 107     /** Return the stylesheet by its position.
 108      * You can obtain the position by, e.g., FindStyleSheetPosition()
 109      * @internal
 110      * Method is not const because the returned style sheet is not const
 111      */
 112     rtl::Reference< SfxStyleSheetBase >
 113     GetStyleSheetByPosition(unsigned pos);
 114
 115     /** Find the position of a provided style.
 116      *
 117      * @throws std::runtime_error if the style has not been found.
 118      */
 119     unsigned
 120     FindStyleSheetPosition(const SfxStyleSheetBase& style) const;
 121
 122     /** Obtain the positions of all styles which have a given name
 123      */
 124     std::vector<unsigned>
 125     FindPositionsByName(const rtl::OUString& name) const;
 126
 127     enum SearchBehavior { RETURN_ALL, RETURN_FIRST };
 128     /** Obtain the positions of all styles which have a certain name and fulfill a certain condition.
 129      *
 130      * This method is fast because it can use the name-based index
 131      */
 132     std::vector<unsigned>
 133     FindPositionsByNameAndPredicate(const rtl::OUString& name, StyleSheetPredicate& predicate,
 134             SearchBehavior behavior = RETURN_ALL) const;
 135
 136     /** Obtain the positions of all styles which fulfill a certain condition.
 137      *
 138      * This method is slow because it cannot use the name-based index
 139      */
 140     std::vector<unsigned>
 141     FindPositionsByPredicate(StyleSheetPredicate& predicate) const;
 142
 143     /** Execute a callback on all style sheets */
 144     void
 145     ApplyToAllStyleSheets(StyleSheetCallback& callback) const;
 146
 147     /** Clear the contents of the index.
 148      * The StyleSheetDisposer::Dispose() method is called on each style sheet, e.g., if you want to broadcast
 149      * changes.
 150      */
 151     void
 152     Clear(StyleSheetDisposer& cleanup);
 153
 154     void
 155     Reindex();
 156
 157     /** Warning: counting for n starts at 0, i.e., the 0th style sheet is the first that is found. */
 158     rtl::Reference<SfxStyleSheetBase>
 159     GetNthStyleSheetThatMatchesPredicate(unsigned n, StyleSheetPredicate& predicate,
 160             unsigned startAt = 0);
 161
 162     /** Get the positions of the style sheets which belong to a certain family.
 163      */
 164     const std::vector<unsigned>&
 165     GetStyleSheetPositionsByFamily(SfxStyleFamily) const;
 166
 167 private:
 168     /** Register the position of a styleName in the index */
 169     void
 170     Register(const SfxStyleSheetBase& style, unsigned pos);
 171
 172     typedef std::vector<rtl::Reference<SfxStyleSheetBase> > VectorType;
 173     /** Vector with the stylesheets to allow for index-based access.
 174      */
 175     VectorType mStyleSheets;
 176
 177     /** The map type that is used to store the mapping from strings to ids in mStyleSheets
 178      *
 179      * @internal
 180      * Must be an unordered map. A regular map is too slow for some files. */
 181     typedef std::unordered_multimap<rtl::OUString, unsigned, rtl::OUStringHash> MapType;
 182
 183     /** A map which stores the positions of style sheets by their name */
 184     MapType mPositionsByName;
 185
 186     std::vector<std::vector<unsigned> > mStyleSheetPositionsByFamily;
 187 };
 188
 189 } /* namespace svl */
 190
 191 #endif // INCLUDED_SVL_INDEXEDSTYLESHEETS_HXX
 192
 193 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */