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/AtomicStringImpl.h>
37
38namespace WebCore {
39
40class Element;
41class TreeScope;
42
43class DocumentOrderedMap {
44public:
45    void add(AtomicStringImpl*, Element*);
46    void remove(AtomicStringImpl*, Element*);
47    void clear();
48
49    bool contains(AtomicStringImpl*) const;
50    bool containsMultiple(AtomicStringImpl*) const;
51    // concrete instantiations of the get<>() method template
52    Element* getElementById(AtomicStringImpl*, const TreeScope*) const;
53    Element* getElementByMapName(AtomicStringImpl*, const TreeScope*) const;
54    Element* getElementByLowercasedMapName(AtomicStringImpl*, const TreeScope*) const;
55
56    void checkConsistency() const;
57
58private:
59    template<bool keyMatches(AtomicStringImpl*, Element*)> Element* get(AtomicStringImpl*, const TreeScope*) const;
60
61    typedef HashMap<AtomicStringImpl*, Element*> Map;
62
63    // We maintain the invariant that m_duplicateCounts is the count of all elements with a given key
64    // excluding the one referenced in m_map, if any. This means it one less than the total count
65    // when the first node with a given key is cached, otherwise the same as the total count.
66    mutable Map m_map;
67    mutable HashCountedSet<AtomicStringImpl*> m_duplicateCounts;
68};
69
70inline bool DocumentOrderedMap::contains(AtomicStringImpl* id) const
71{
72    return m_map.contains(id) || m_duplicateCounts.contains(id);
73}
74
75inline bool DocumentOrderedMap::containsMultiple(AtomicStringImpl* id) const
76{
77    return m_duplicateCounts.contains(id);
78}
79
80} // namespace WebCore
81
82#endif // DocumentOrderedMap_h
83
84