source: trunk/src/qt3support/tools/q3gcache.h@ 792

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#ifndef Q3GCACHE_H
#define Q3GCACHE_H

#include <Qt3Support/q3ptrcollection.h>
#include <Qt3Support/q3glist.h>
#include <Qt3Support/q3gdict.h>

QT_BEGIN_HEADER

QT_BEGIN_NAMESPACE

QT_MODULE(Qt3SupportLight)

class Q3CList;                                  // internal classes
class Q3CListIt;
class Q3CDict;

class Q_COMPAT_EXPORT Q3GCache : public Q3PtrCollection // generic LRU cache
{
friend class Q3GCacheIterator;
protected:
    enum KeyType { StringKey, AsciiKey, IntKey, PtrKey };
      // identical to Q3GDict's, but PtrKey is not used at the moment

    Q3GCache(int maxCost, uint size, KeyType kt, bool caseSensitive,
             bool copyKeys);
    Q3GCache(const Q3GCache &);                 // not allowed, calls fatal()
   ~Q3GCache();
    Q3GCache &operator=(const Q3GCache &);      // not allowed, calls fatal()

    uint    count()     const;
    uint    size()      const;
    int     maxCost()   const   { return mCost; }
    int     totalCost() const   { return tCost; }
    void    setMaxCost(int maxCost);
    void    clear();

    bool    insert_string(const QString &key, Q3PtrCollection::Item,
                           int cost, int priority);
    bool    insert_other(const char *key, Q3PtrCollection::Item,
                          int cost, int priority);
    bool    remove_string(const QString &key);
    bool    remove_other(const char *key);
    Q3PtrCollection::Item take_string(const QString &key);
    Q3PtrCollection::Item take_other(const char *key);

    Q3PtrCollection::Item find_string(const QString &key, bool ref=true) const;
    Q3PtrCollection::Item find_other(const char *key, bool ref=true) const;

    void    statistics() const;

private:
    bool    makeRoomFor(int cost, int priority = -1);
    KeyType keytype;
    Q3CList *lruList;
    Q3CDict *dict;
    int     mCost;
    int     tCost;
    bool    copyk;
};


class Q_COMPAT_EXPORT Q3GCacheIterator                  // generic cache iterator
{
protected:
    Q3GCacheIterator(const Q3GCache &);
    Q3GCacheIterator(const Q3GCacheIterator &);
   ~Q3GCacheIterator();
    Q3GCacheIterator &operator=(const Q3GCacheIterator &);

    uint              count()   const;
    bool              atFirst() const;
    bool              atLast()  const;
    Q3PtrCollection::Item toFirst();
    Q3PtrCollection::Item toLast();

    Q3PtrCollection::Item get() const;
    QString           getKeyString() const;
    const char       *getKeyAscii()  const;
    long              getKeyInt()    const;

    Q3PtrCollection::Item operator()();
    Q3PtrCollection::Item operator++();
    Q3PtrCollection::Item operator+=(uint);
    Q3PtrCollection::Item operator--();
    Q3PtrCollection::Item operator-=(uint);

protected:
    Q3CListIt *it;                              // iterator on cache list
};

QT_END_NAMESPACE

QT_END_HEADER

#endif // Q3GCACHE_H