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1 /*
2 ********************************************************************************
3 * Copyright (C) 1997-2006, International Business Machines
4 * Corporation and others. All Rights Reserved.
5 ********************************************************************************
6 *
7 * File FIELDPOS.H
8 *
9 * Modification History:
10 *
11 * Date Name Description
12 * 02/25/97 aliu Converted from java.
13 * 03/17/97 clhuang Updated per Format implementation.
14 * 07/17/98 stephen Added default/copy ctors, and operators =, ==, !=
15 ********************************************************************************
16 */
17
18 // *****************************************************************************
19 // This file was generated from the java source file FieldPosition.java
20 // *****************************************************************************
21
22 #ifndef FIELDPOS_H
23 #define FIELDPOS_H
24
25 #include "unicode/utypes.h"
26
27 /**
28 * \file
29 * \brief C++ API: FieldPosition identifies the fields in a formatted output.
30 */
31
32 #if !UCONFIG_NO_FORMATTING
33
34 #include "unicode/uobject.h"
35
36 U_NAMESPACE_BEGIN
37
38 /**
39 * <code>FieldPosition</code> is a simple class used by <code>Format</code>
40 * and its subclasses to identify fields in formatted output. Fields are
41 * identified by constants, whose names typically end with <code>_FIELD</code>,
42 * defined in the various subclasses of <code>Format</code>. See
43 * <code>ERA_FIELD</code> and its friends in <code>DateFormat</code> for
44 * an example.
45 *
46 * <p>
47 * <code>FieldPosition</code> keeps track of the position of the
48 * field within the formatted output with two indices: the index
49 * of the first character of the field and the index of the last
50 * character of the field.
51 *
52 * <p>
53 * One version of the <code>format</code> method in the various
54 * <code>Format</code> classes requires a <code>FieldPosition</code>
55 * object as an argument. You use this <code>format</code> method
56 * to perform partial formatting or to get information about the
57 * formatted output (such as the position of a field).
58 *
59 * The FieldPosition class is not suitable for subclassing.
60 *
61 * <p>
62 * Below is an example of using <code>FieldPosition</code> to aid
63 * alignment of an array of formatted floating-point numbers on
64 * their decimal points:
65 * <pre>
66 * \code
67 * double doubleNum[] = {123456789.0, -12345678.9, 1234567.89, -123456.789,
68 * 12345.6789, -1234.56789, 123.456789, -12.3456789, 1.23456789};
69 * int dNumSize = (int)(sizeof(doubleNum)/sizeof(double));
70 *
71 * UErrorCode status = U_ZERO_ERROR;
72 * DecimalFormat* fmt = (DecimalFormat*) NumberFormat::createInstance(status);
73 * fmt->setDecimalSeparatorAlwaysShown(true);
74 *
75 * const int tempLen = 20;
76 * char temp[tempLen];
77 *
78 * for (int i=0; i<dNumSize; i++) {
79 * FieldPosition pos(NumberFormat::INTEGER_FIELD);
80 * UnicodeString buf;
81 * char fmtText[tempLen];
82 * ToCharString(fmt->format(doubleNum[i], buf, pos), fmtText);
83 * for (int j=0; j<tempLen; j++) temp[j] = ' '; // clear with spaces
84 * temp[__min(tempLen, tempLen-pos.getEndIndex())] = '\0';
85 * cout << temp << fmtText << endl;
86 * }
87 * delete fmt;
88 * \endcode
89 * </pre>
90 * <p>
91 * The code will generate the following output:
92 * <pre>
93 * \code
94 * 123,456,789.000
95 * -12,345,678.900
96 * 1,234,567.880
97 * -123,456.789
98 * 12,345.678
99 * -1,234.567
100 * 123.456
101 * -12.345
102 * 1.234
103 * \endcode
104 * </pre>
105 */
106 class U_I18N_API FieldPosition : public UObject {
107 public:
108 /**
109 * DONT_CARE may be specified as the field to indicate that the
110 * caller doesn't need to specify a field. Do not subclass.
111 */
112 enum { DONT_CARE = -1 };
113
114 /**
115 * Creates a FieldPosition object with a non-specified field.
116 * @stable ICU 2.0
117 */
118 FieldPosition()
119 : UObject(), fField(DONT_CARE), fBeginIndex(0), fEndIndex(0) {}
120
121 /**
122 * Creates a FieldPosition object for the given field. Fields are
123 * identified by constants, whose names typically end with _FIELD,
124 * in the various subclasses of Format.
125 *
126 * @see NumberFormat#INTEGER_FIELD
127 * @see NumberFormat#FRACTION_FIELD
128 * @see DateFormat#YEAR_FIELD
129 * @see DateFormat#MONTH_FIELD
130 * @stable ICU 2.0
131 */
132 FieldPosition(int32_t field)
133 : UObject(), fField(field), fBeginIndex(0), fEndIndex(0) {}
134
135 /**
136 * Copy constructor
137 * @param copy the object to be copied from.
138 * @stable ICU 2.0
139 */
140 FieldPosition(const FieldPosition& copy)
141 : UObject(copy), fField(copy.fField), fBeginIndex(copy.fBeginIndex), fEndIndex(copy.fEndIndex) {}
142
143 /**
144 * Destructor
145 * @stable ICU 2.0
146 */
147 virtual ~FieldPosition();
148
149 /**
150 * Assignment operator
151 * @param copy the object to be copied from.
152 * @stable ICU 2.0
153 */
154 FieldPosition& operator=(const FieldPosition& copy);
155
156 /**
157 * Equality operator.
158 * @param that the object to be compared with.
159 * @return TRUE if the two field positions are equal, FALSE otherwise.
160 * @stable ICU 2.0
161 */
162 UBool operator==(const FieldPosition& that) const;
163
164 /**
165 * Equality operator.
166 * @param that the object to be compared with.
167 * @return TRUE if the two field positions are not equal, FALSE otherwise.
168 * @stable ICU 2.0
169 */
170 UBool operator!=(const FieldPosition& that) const;
171
172 /**
173 * Clone this object.
174 * Clones can be used concurrently in multiple threads.
175 * If an error occurs, then NULL is returned.
176 * The caller must delete the clone.
177 *
178 * @return a clone of this object
179 *
180 * @see getDynamicClassID
181 * @stable ICU 2.8
182 */
183 FieldPosition *clone() const;
184
185 /**
186 * Retrieve the field identifier.
187 * @return the field identifier.
188 * @stable ICU 2.0
189 */
190 int32_t getField(void) const { return fField; }
191
192 /**
193 * Retrieve the index of the first character in the requested field.
194 * @return the index of the first character in the requested field.
195 * @stable ICU 2.0
196 */
197 int32_t getBeginIndex(void) const { return fBeginIndex; }
198
199 /**
200 * Retrieve the index of the character following the last character in the
201 * requested field.
202 * @return the index of the character following the last character in the
203 * requested field.
204 * @stable ICU 2.0
205 */
206 int32_t getEndIndex(void) const { return fEndIndex; }
207
208 /**
209 * Set the field.
210 * @param f the new value of the field.
211 * @stable ICU 2.0
212 */
213 void setField(int32_t f) { fField = f; }
214
215 /**
216 * Set the begin index. For use by subclasses of Format.
217 * @param bi the new value of the begin index
218 * @stable ICU 2.0
219 */
220 void setBeginIndex(int32_t bi) { fBeginIndex = bi; }
221
222 /**
223 * Set the end index. For use by subclasses of Format.
224 * @param ei the new value of the end index
225 * @stable ICU 2.0
226 */
227 void setEndIndex(int32_t ei) { fEndIndex = ei; }
228
229 /**
230 * ICU "poor man's RTTI", returns a UClassID for the actual class.
231 *
232 * @stable ICU 2.2
233 */
234 virtual UClassID getDynamicClassID() const;
235
236 /**
237 * ICU "poor man's RTTI", returns a UClassID for this class.
238 *
239 * @stable ICU 2.2
240 */
241 static UClassID U_EXPORT2 getStaticClassID();
242
243 private:
244 /**
245 * Input: Desired field to determine start and end offsets for.
246 * The meaning depends on the subclass of Format.
247 */
248 int32_t fField;
249
250 /**
251 * Output: Start offset of field in text.
252 * If the field does not occur in the text, 0 is returned.
253 */
254 int32_t fBeginIndex;
255
256 /**
257 * Output: End offset of field in text.
258 * If the field does not occur in the text, 0 is returned.
259 */
260 int32_t fEndIndex;
261 };
262
263 inline FieldPosition&
264 FieldPosition::operator=(const FieldPosition& copy)
265 {
266 fField = copy.fField;
267 fEndIndex = copy.fEndIndex;
268 fBeginIndex = copy.fBeginIndex;
269 return *this;
270 }
271
272 inline UBool
273 FieldPosition::operator==(const FieldPosition& copy) const
274 {
275 return (fField == copy.fField &&
276 fEndIndex == copy.fEndIndex &&
277 fBeginIndex == copy.fBeginIndex);
278 }
279
280 inline UBool
281 FieldPosition::operator!=(const FieldPosition& copy) const
282 {
283 return !operator==(copy);
284 }
285
286 U_NAMESPACE_END
287
288 #endif /* #if !UCONFIG_NO_FORMATTING */
289
290 #endif // _FIELDPOS
291 //eof