1/*
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3 *
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9 * notice, this list of conditions and the following disclaimer.
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12 * in the documentation and/or other materials provided with the
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17 *
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29 */
30
31#ifndef DocumentOrderedMap_h
32#define DocumentOrderedMap_h
33
34#include "wtf/HashCountedSet.h"
35#include "wtf/HashMap.h"
36#include "wtf/text/StringImpl.h"
37
38namespace WebCore {
39
40class Element;
41class TreeScope;
42
43class DocumentOrderedMap {
44public:
45    void add(StringImpl*, Element*);
46    void remove(StringImpl*, Element*);
47    void clear();
48
49    bool contains(StringImpl*) const;
50    bool containsMultiple(StringImpl*) const;
51    // concrete instantiations of the get<>() method template
52    Element* getElementById(StringImpl*, const TreeScope*) const;
53    Element* getElementByMapName(StringImpl*, const TreeScope*) const;
54    Element* getElementByLowercasedMapName(StringImpl*, const TreeScope*) const;
55    Element* getElementByLabelForAttribute(StringImpl*, const TreeScope*) const;
56
57    void checkConsistency() const;
58
59private:
60    template<bool keyMatches(StringImpl*, Element*)> Element* get(StringImpl*, const TreeScope*) const;
61
62    typedef HashMap<StringImpl*, Element*> Map;
63
64    // We maintain the invariant that m_duplicateCounts is the count of all elements with a given key
65    // excluding the one referenced in m_map, if any. This means it one less than the total count
66    // when the first node with a given key is cached, otherwise the same as the total count.
67    mutable Map m_map;
68    mutable HashCountedSet<StringImpl*> m_duplicateCounts;
69};
70
71inline bool DocumentOrderedMap::contains(StringImpl* id) const
72{
73    return m_map.contains(id) || m_duplicateCounts.contains(id);
74}
75
76inline bool DocumentOrderedMap::containsMultiple(StringImpl* id) const
77{
78    return m_duplicateCounts.contains(id);
79}
80
81} // namespace WebCore
82
83#endif // DocumentOrderedMap_h
84