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50
51 #include <QCache>
52 #include <QMutex>
53 #include <QThreadStorage>
54
55 #define Counter ReentrantCounter
56
57 //! [3]
58 class Counter
59 //! [3] //! [4]
60 {
61 public:
Counter()62 Counter() { n = 0; }
63
increment()64 void increment() { ++n; }
decrement()65 void decrement() { --n; }
value() const66 int value() const { return n; }
67
68 private:
69 int n;
70 };
71 //! [4]
72
73 #undef Counter
74 #define Counter ThreadSafeCounter
75
76 //! [5]
77 class Counter
78 //! [5] //! [6]
79 {
80 public:
Counter()81 Counter() { n = 0; }
82
increment()83 void increment() { QMutexLocker locker(&mutex); ++n; }
decrement()84 void decrement() { QMutexLocker locker(&mutex); --n; }
value() const85 int value() const { QMutexLocker locker(&mutex); return n; }
86
87 private:
88 mutable QMutex mutex;
89 int n;
90 };
91 //! [6]
92
93 typedef int SomeClass;
94
95 //! [7]
96 QThreadStorage<QCache<QString, SomeClass> > caches;
97
cacheObject(const QString & key,SomeClass * object)98 void cacheObject(const QString &key, SomeClass *object)
99 //! [7] //! [8]
100 {
101 caches.localData().insert(key, object);
102 }
103
removeFromCache(const QString & key)104 void removeFromCache(const QString &key)
105 //! [8] //! [9]
106 {
107 if (!caches.hasLocalData())
108 return;
109
110 caches.localData().remove(key);
111 }
112 //! [9]
113
main()114 int main()
115 {
116 return 0;
117 }
118