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39
40#ifndef QNETWORKACCESSCACHE_P_H
41#define QNETWORKACCESSCACHE_P_H
42
43//
44// W A R N I N G
45// -------------
46//
47// This file is not part of the Qt API. It exists for the convenience
48// of the Network Access API. This header file may change from
49// version to version without notice, or even be removed.
50//
51// We mean it.
52//
53
54#include <QtNetwork/private/qtnetworkglobal_p.h>
55#include "QtCore/qobject.h"
56#include "QtCore/qbasictimer.h"
57#include "QtCore/qbytearray.h"
58#include "QtCore/qhash.h"
59#include "QtCore/qmetatype.h"
60
61QT_BEGIN_NAMESPACE
62
63class QNetworkRequest;
64class QUrl;
65
66// this class is not about caching files but about
67// caching objects used by QNetworkAccessManager, e.g. existing TCP connections
68// or credentials.
69class QNetworkAccessCache: public QObject
70{
71 Q_OBJECT
72public:
73 struct Node;
74 typedef QHash<QByteArray, Node> NodeHash;
75
76 class CacheableObject
77 {
78 friend class QNetworkAccessCache;
79 QByteArray key;
80 bool expires;
81 bool shareable;
82 public:
83 CacheableObject();
84 virtual ~CacheableObject();
85 virtual void dispose() = 0;
86 inline QByteArray cacheKey() const { return key; }
87
88 protected:
89 void setExpires(bool enable);
90 void setShareable(bool enable);
91 };
92
93 QNetworkAccessCache();
94 ~QNetworkAccessCache();
95
96 void clear();
97
98 void addEntry(const QByteArray &key, CacheableObject *entry);
99 bool hasEntry(const QByteArray &key) const;
100 bool requestEntry(const QByteArray &key, QObject *target, const char *member);
101 CacheableObject *requestEntryNow(const QByteArray &key);
102 void releaseEntry(const QByteArray &key);
103 void removeEntry(const QByteArray &key);
104
105signals:
106 void entryReady(QNetworkAccessCache::CacheableObject *);
107
108protected:
109 void timerEvent(QTimerEvent *) override;
110
111private:
112 // idea copied from qcache.h
113 NodeHash hash;
114 Node *oldest;
115 Node *newest;
116
117 QBasicTimer timer;
118
119 void linkEntry(const QByteArray &key);
120 bool unlinkEntry(const QByteArray &key);
121 void updateTimer();
122 bool emitEntryReady(Node *node, QObject *target, const char *member);
123};
124
125QT_END_NAMESPACE
126
127Q_DECLARE_METATYPE(QNetworkAccessCache::CacheableObject*)
128
129#endif
130

source code of qtbase/src/network/access/qnetworkaccesscache_p.h