2 mike 1.1 //
3 // Copyright (c) 2000, 2001, 2002 BMC Software; Hewlett-Packard Development
4 // Company, L.P.; IBM Corp.; The Open Group; Tivoli Systems.
5 // Copyright (c) 2003 BMC Software; Hewlett-Packard Development Company, L.P.;
6 // IBM Corp.; EMC Corporation, The Open Group.
7 // Copyright (c) 2004 BMC Software; Hewlett-Packard Development Company, L.P.;
8 // IBM Corp.; EMC Corporation; VERITAS Software Corporation; The Open Group.
9 // Copyright (c) 2005 Hewlett-Packard Development Company, L.P.; IBM Corp.;
10 // EMC Corporation; VERITAS Software Corporation; The Open Group.
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13 mike 1.1 //
14 // Permission is hereby granted, free of charge, to any person obtaining a copy
15 // of this software and associated documentation files (the "Software"), to
16 // deal in the Software without restriction, including without limitation the
17 // rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
18 // sell copies of the Software, and to permit persons to whom the Software is
19 // furnished to do so, subject to the following conditions:
20 //
21 // THE ABOVE COPYRIGHT NOTICE AND THIS PERMISSION NOTICE SHALL BE INCLUDED IN
22 // ALL COPIES OR SUBSTANTIAL PORTIONS OF THE SOFTWARE. THE SOFTWARE IS PROVIDED
23 // "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT
24 // LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
25 // PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
26 // HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
27 // ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
28 // WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
29 //
30 //==============================================================================
31 //
32 // Author: Michael E. Brasher, Inova Europe (mike-brasher@austin.rr.com)
33 //
34 mike 1.1 //%/////////////////////////////////////////////////////////////////////////////
35
36 #ifndef Pegasus_ArrayIterator_h
37 #define Pegasus_ArrayIterator_h
38
39 #include <Pegasus/Common/Array.h>
40
41 PEGASUS_NAMESPACE_BEGIN
42
43 //
44 // This class provides a faster way of iterating arrays. Due to the expense
45 // of calling operator[], iteration is slower than necessary. Consider this
46 // example:
47 //
48 // Array<Uint32> array;
49 // Uint32 sum = 0;
50 //
51 // for (Uint32 i = 0, n = array.size(); i < n; i++)
52 // sum += array[i];
53 //
54 // Every use of array[i] results in a function call that checks for a bounds
55 mike 1.1 // violation. We can see that an array bounds violation is impossible in this
56 // case. We can use the ConstArrayIterator class to eliminate this overhead.
57 //
58 // Array<Uint32> array;
59 // Uint32 sum = 0;
60 //
61 // ConstArrayIterator<Uint32> iterator(array);
62 //
63 // for (Uint32 i = 0; i < iterator.size(); i++)
64 // sum += iterator[i];
65 //
66 // The constructor pre-saves the array size and data before entering the loop
67 // so that iterator.size() and iterator[i] are trivial inline functions that
68 // access these members.
69 //
70 template<class T>
71 class ConstArrayIterator
72 {
73 public:
74
75 ConstArrayIterator(const Array<T>& x) : _data(x.getData()), _size(x.size())
76 mike 1.1 {
77 }
78
79 Uint32 size() const
80 {
81 return _size;
82 }
83
84 const T& operator[](Uint32 i) const
85 {
86 PEGASUS_DEBUG_ASSERT(i < _size);
87 return _data[i];
88 }
89
90 private:
91
92 ConstArrayIterator& operator=(const ConstArrayIterator<T>& x);
93 ConstArrayIterator(const ConstArrayIterator<T>& x);
94
95 const T* _data;
96 Uint32 _size;
97 mike 1.1 };
98
99 //
100 // This class is similar to ConstArrayIterator except it provides a non-const
101 // version of operator[].
102 //
103 template<class T>
104 class ArrayIterator
105 {
106 public:
107
108 ArrayIterator(Array<T>& x) : _data((T*)x.getData()), _size(x.size())
109 {
110 }
111
112 Uint32 size() const
113 {
114 return _size;
115 }
116
117 const T& operator[](Uint32 i) const
118 mike 1.1 {
119 PEGASUS_DEBUG_ASSERT(i < _size);
120 return _data[i];
121 }
122
123 T& operator[](Uint32 i)
124 {
125 PEGASUS_DEBUG_ASSERT(i < _size);
126 return _data[i];
127 }
128
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