]>
Commit | Line | Data |
---|---|---|
da0e9ce3 | 1 | /******************************************************************************* |
2 | * Project: BaBar detector at the SLAC PEP-II B-factory | |
3 | * Package: EvtGenBase | |
4 | * File: $Id: EvtStreamInputIterator.hh,v 1.1 2003/03/03 05:38:22 dvoretsk Exp $ | |
5 | * Author: Alexei Dvoretskii, dvoretsk@slac.stanford.edu, 2001-2002 | |
6 | * | |
7 | * Copyright (C) 2002 Caltech | |
8 | *******************************************************************************/ | |
9 | ||
10 | // Adapters are used to convert various types of input streams | |
11 | // into an iteratable interface. | |
12 | ||
13 | #ifndef EVT_STREAM_INPUT_ITERATOR_HH | |
14 | #define EVT_STREAM_INPUT_ITERATOR_HH | |
15 | ||
16 | #include "EvtGenBase/EvtStreamAdapter.hh" | |
17 | #include <iterator> | |
18 | using std::input_iterator_tag; | |
19 | ||
20 | template <class Point> | |
21 | class EvtStreamInputIterator { | |
22 | public: | |
23 | ||
24 | typedef input_iterator_tag iterator_category; | |
25 | typedef Point value_type; | |
da0e9ce3 | 26 | typedef const Point* pointer; |
27 | typedef const Point& reference; | |
28 | ||
29 | EvtStreamInputIterator() | |
30 | : _counter(0) | |
31 | {} | |
32 | ||
33 | EvtStreamInputIterator(const EvtStreamInputIterator& other) | |
34 | : _counter(other._counter ? other._counter->clone() : 0), | |
35 | _currentValue(other._currentValue) | |
36 | {} | |
37 | ||
38 | EvtStreamInputIterator(EvtStreamAdapter<Point>& counter) | |
39 | : _counter(counter.clone()) | |
40 | { | |
41 | _currentValue = _counter->currentValue(); | |
42 | } | |
43 | ||
44 | ~EvtStreamInputIterator() | |
45 | { | |
46 | if(_counter) delete _counter; | |
47 | } | |
48 | ||
49 | reference operator*() const | |
50 | { | |
51 | return _currentValue; | |
52 | } | |
53 | ||
54 | EvtStreamInputIterator& operator++() | |
55 | { | |
56 | _read(); | |
57 | return *this; | |
58 | } | |
59 | ||
60 | EvtStreamInputIterator operator++(int) | |
61 | { | |
62 | EvtStreamInputIterator tmp = *this; | |
63 | _read(); | |
64 | return tmp; | |
65 | } | |
66 | ||
67 | bool operator==(const EvtStreamInputIterator& other) const | |
68 | { | |
69 | // Equality is only defined for two past the end iterators | |
70 | return (pastEnd() && other.pastEnd()); | |
71 | } | |
72 | ||
73 | protected: | |
74 | ||
75 | EvtStreamAdapter<Point>* _counter; | |
76 | value_type _currentValue; | |
77 | ||
78 | bool pastEnd() const | |
79 | { | |
80 | bool ret = true; | |
81 | if(_counter) ret = _counter->pastEnd(); | |
82 | return ret; | |
83 | } | |
84 | ||
85 | // Advances the iterator | |
86 | ||
87 | void _read() { | |
88 | ||
89 | _counter->advance(); | |
90 | _currentValue = _counter->currentValue(); | |
91 | } | |
92 | }; | |
93 | ||
94 | ||
95 | // For adaptable generators these shorthand functions can be used | |
96 | // to construct iterators. | |
97 | ||
98 | template <class Generator> | |
99 | EvtStreamInputIterator<typename Generator::result_type> iter(Generator gen, int N = 0) | |
100 | { | |
101 | typedef typename Generator::result_type Point; | |
102 | EvtGenStreamAdapter<Point,Generator> counter(gen,N); | |
103 | return EvtStreamInputIterator<Point>(counter); | |
104 | } | |
105 | ||
106 | ||
107 | #endif | |
108 | ||
109 | ||
110 |