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1 : /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
2 : /*
3 : * This file is part of the LibreOffice project.
4 : *
5 : * This Source Code Form is subject to the terms of the Mozilla Public
6 : * License, v. 2.0. If a copy of the MPL was not distributed with this
7 : * file, You can obtain one at http://mozilla.org/MPL/2.0/.
8 : *
9 : * This file incorporates work covered by the following license notice:
10 : *
11 : * Licensed to the Apache Software Foundation (ASF) under one or more
12 : * contributor license agreements. See the NOTICE file distributed
13 : * with this work for additional information regarding copyright
14 : * ownership. The ASF licenses this file to you under the Apache
15 : * License, Version 2.0 (the "License"); you may not use this file
16 : * except in compliance with the License. You may obtain a copy of
17 : * the License at http://www.apache.org/licenses/LICENSE-2.0 .
18 : */
19 :
20 : #ifndef INCLUDED_UNOTOOLS_DIGITGROUPINGITERATOR_HXX
21 : #define INCLUDED_UNOTOOLS_DIGITGROUPINGITERATOR_HXX
22 :
23 : #include <com/sun/star/uno/Sequence.hxx>
24 :
25 : namespace utl {
26 :
27 : /** Iterator to be used with a digit grouping as obtained through
28 : LocaleDataWrapper::getDigitGrouping().
29 :
30 : The iterator advances over the digit groupings, returning the number of
31 : digits per group. If the last group was encountered the iterator will
32 : always return the last grouping.
33 :
34 : Grouping values are sanitized to be 0 <= value <= SAL_MAX_UINT16, even if
35 : originally Int32, to be able to easily cast it down to String's xub_StrLen.
36 : This shouldn't make any difference in practice.
37 :
38 : Usage example with a string buffer containing a decimal representation of
39 : an integer number. Note that of course this loop could be optimized to not
40 : count single characters but hunks of groups instead using the get() method,
41 : this is just for illustrating usage. Anyway, for double values it is highly
42 : more efficient to use ::rtl::math::doubleToString() and pass the grouping
43 : sequence, instead of using this iterator and inserting charcters into
44 : strings.
45 :
46 : DigitGroupingIterator aGrouping(...)
47 : sal_Int32 nCount = 0;
48 : sal_Int32 n = aBuffer.getLength();
49 : // >1 because we don't want to insert a separator if there is no leading digit.
50 : while (n-- > 1)
51 : {
52 : if (++nCount >= aGrouping.getPos())
53 : {
54 : aBuffer.insert( n, cSeparator);
55 : nGroupDigits = aGrouping.advance();
56 : }
57 : }
58 :
59 : */
60 :
61 0 : class DigitGroupingIterator
62 : {
63 : const ::com::sun::star::uno::Sequence< sal_Int32 > maGroupings;
64 :
65 : sal_Int32 mnGroup; // current active grouping
66 : sal_Int32 mnDigits; // current active digits per group
67 : sal_Int32 mnNextPos; // position (in digits) of next grouping
68 :
69 0 : void setInfinite()
70 : {
71 0 : mnGroup = maGroupings.getLength();
72 0 : }
73 :
74 0 : bool isInfinite() const
75 : {
76 0 : return mnGroup >= maGroupings.getLength();
77 : }
78 :
79 0 : sal_Int32 getGrouping() const
80 : {
81 0 : if (mnGroup < maGroupings.getLength())
82 : {
83 0 : sal_Int32 n = maGroupings[mnGroup];
84 : OSL_ENSURE( 0 <= n && n <= SAL_MAX_UINT16, "DigitGroupingIterator::getGrouping: far out");
85 0 : if (n < 0)
86 0 : n = 0; // sanitize ...
87 0 : else if (n > SAL_MAX_UINT16)
88 0 : n = SAL_MAX_UINT16; // limit for use with xub_StrLen
89 0 : return n;
90 : }
91 0 : return 0;
92 : }
93 :
94 0 : void setPos()
95 : {
96 : // someone might be playing jokes on us, so check for overflow
97 0 : if (mnNextPos <= SAL_MAX_INT32 - mnDigits)
98 0 : mnNextPos += mnDigits;
99 0 : }
100 :
101 0 : void setDigits()
102 : {
103 0 : sal_Int32 nPrev = mnDigits;
104 0 : mnDigits = getGrouping();
105 0 : if (!mnDigits)
106 : {
107 0 : mnDigits = nPrev;
108 0 : setInfinite();
109 : }
110 0 : setPos();
111 0 : }
112 :
113 0 : void initGrouping()
114 : {
115 0 : mnDigits = 3; // just in case of constructed with empty grouping
116 0 : mnGroup = 0;
117 0 : mnNextPos = 0;
118 0 : setDigits();
119 0 : }
120 :
121 : // not implemented, prevent usage
122 : DigitGroupingIterator();
123 : DigitGroupingIterator( const DigitGroupingIterator & );
124 : DigitGroupingIterator & operator=( const DigitGroupingIterator & );
125 :
126 : public:
127 :
128 0 : explicit DigitGroupingIterator( const ::com::sun::star::uno::Sequence< sal_Int32 > & rGroupings )
129 0 : : maGroupings( rGroupings)
130 : {
131 0 : initGrouping();
132 0 : }
133 :
134 : /** Advance iterator to next grouping. */
135 0 : DigitGroupingIterator & advance()
136 : {
137 0 : if (isInfinite())
138 0 : setPos();
139 : else
140 : {
141 0 : ++mnGroup;
142 0 : setDigits();
143 : }
144 0 : return *this;
145 : }
146 :
147 : /** Obtain current grouping. Always > 0. */
148 : sal_Int32 get() const
149 : {
150 : return mnDigits;
151 : }
152 :
153 : /** The next position (in integer digits) from the right where to insert a
154 : group separator. */
155 0 : sal_Int32 getPos()
156 : {
157 0 : return mnNextPos;
158 : }
159 :
160 : /** Reset iterator to start again from the right beginning. */
161 : void reset()
162 : {
163 : initGrouping();
164 : }
165 :
166 : /** Create a sequence of bool values containing positions where to add a
167 : separator when iterating forward over a string and copying digit per
168 : digit. For example, for grouping in thousands and nIntegerDigits==7 the
169 : sequence returned would be {1,0,0,1,0,0,0} so the caller would add a
170 : separator after the 1st and the 4th digit. */
171 0 : static ::com::sun::star::uno::Sequence< sal_Bool > createForwardSequence(
172 : sal_Int32 nIntegerDigits,
173 : const ::com::sun::star::uno::Sequence< sal_Int32 > & rGroupings )
174 : {
175 0 : if (nIntegerDigits <= 0)
176 0 : return ::com::sun::star::uno::Sequence< sal_Bool >();
177 0 : DigitGroupingIterator aIterator( rGroupings);
178 0 : ::com::sun::star::uno::Sequence< sal_Bool > aSeq( nIntegerDigits);
179 0 : sal_Bool* pArr = aSeq.getArray();
180 0 : for (sal_Int32 j = 0; --nIntegerDigits >= 0; ++j)
181 : {
182 0 : if (j == aIterator.getPos())
183 : {
184 0 : pArr[nIntegerDigits] = sal_True;
185 0 : aIterator.advance();
186 : }
187 : else
188 0 : pArr[nIntegerDigits] = sal_False;
189 : }
190 0 : return aSeq;
191 : }
192 : };
193 :
194 : } // namespace utl
195 :
196 : #endif // INCLUDED_UNOTOOLS_DIGITGROUPINGITERATOR_HXX
197 :
198 : /* vim:set shiftwidth=4 softtabstop=4 expandtab: */
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