summaryrefslogtreecommitdiff
path: root/libopie/pim/opimaccessbackend.h
blob: 4f00bc93aeed201d1af2c21a84edfe8cd7b6bb9f (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
#ifndef OPIE_PIM_ACCESS_BACKEND
#define OPIE_PIM_ACCESS_BACKEND

#include <qarray.h>

#include <opie/otemplatebase.h>
#include <opie/opimrecord.h>


/**
 * OPimAccessBackend is the base class
 * for all private backends
 * it operates on OPimRecord as the base class
 * and it's responsible for fast manipulating
 * the resource the implementation takes care
 *  of
 */
template <class T = OPimRecord>
class OPimAccessBackend {
public:
    typedef OTemplateBase<T> Frontend;
    OPimAccessBackend();
    virtual ~OPimAccessBackend();

    /**
     * load the resource
     */
    virtual bool load() = 0;

    /**
     * reload the resource
     */
    virtual bool reload() = 0;

    /**
     * save the resource and
     * all it's changes
     */
    virtual bool save() = 0;

    /**
     * return an array of
     * all available uids
     */
    virtual QArray<int> allRecords()const = 0;

    /**
     * queryByExample for T with the SortOrder
     * sort
     */
    virtual QArray<int> queryByExample( const T& t, int sort ) = 0;

    /**
     * find the OPimRecord with uid @param uid
     * returns T and T.isEmpty() if nothing was found
     */
    virtual T find(int uid )const  = 0;

    virtual T find(int uid, const QArray<int>& items,
                   uint current, typename Frontend::CacheDirection )const ;
    /**
     * clear the back end
     */
    virtual void clear() = 0;

    /**
     * add T
     */
    virtual bool add( const T& t ) = 0;

    /**
     * remove
     */
    virtual bool remove( int uid ) = 0;

    /**
     * replace a record with T.uid()
     */
    virtual bool replace( const T& t ) = 0;

    /*
     * setTheFrontEnd!!!
     */
    void setFrontend( Frontend* front );

    /**
     * set the read ahead count
     */
    void setReadAhead( uint count );
protected:
    void cache( const T& t )const;

    /**
     * use a prime number here!
     */
    void setSaneCacheSize( int );

    uint readAhead()const;

private:
    Frontend* m_front;
    uint m_read;

};

template <class T>
OPimAccessBackend<T>::OPimAccessBackend() {
    m_front = 0l;
}
template <class T>
OPimAccessBackend<T>::~OPimAccessBackend() {

}
template <class T>
void OPimAccessBackend<T>::setFrontend( Frontend* fr ) {
    m_front = fr;
}
template <class T>
void OPimAccessBackend<T>::cache( const T& t )const {
    if (m_front )
        m_front->cache( t );
}
template <class T>
void OPimAccessBackend<T>::setSaneCacheSize( int size) {
    if (m_front )
        m_front->setSaneCacheSize( size );
}
template <class T>
T OPimAccessBackend<T>::find( int uid, const QArray<int>&,
                              uint, typename Frontend::CacheDirection )const {
    return find( uid );
}
template <class T>
void OPimAccessBackend<T>::setReadAhead( uint count ) {
    m_read = count;
}
template <class T>
uint OPimAccessBackend<T>::readAhead()const {
    return m_read;
}
#endif