aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/libs/icu/i18n/japancal.h
blob: 88513440528b043caa59fc0387ef6e3d64e494c6 (plain) (blame)
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
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
 ********************************************************************************
 * Copyright (C) 2003-2008, International Business Machines Corporation
 * and others. All Rights Reserved.
 ********************************************************************************
 *
 * File JAPANCAL.H
 *
 * Modification History:
 *
 *   Date        Name        Description
 *   05/13/2003  srl         copied from gregocal.h
 ********************************************************************************
 */

#ifndef JAPANCAL_H
#define JAPANCAL_H

#include "unicode/utypes.h"

#if !UCONFIG_NO_FORMATTING

#include "unicode/calendar.h"
#include "unicode/gregocal.h"

U_NAMESPACE_BEGIN

/**
 * Concrete class which provides the Japanese calendar.
 * <P>
 * <code>JapaneseCalendar</code> is a subclass of <code>GregorianCalendar</code>
 * that numbers years and eras based on the reigns of the Japanese emperors.
 * The Japanese calendar is identical to the Gregorian calendar in all respects
 * except for the year and era.  The ascension of each  emperor to the throne
 * begins a new era, and the years of that era are numbered starting with the
 * year of ascension as year 1.
 * <p>
 * Note that in the year of an imperial ascension, there are two possible sets
 * of year and era values: that for the old era and for the new.  For example, a
 * new era began on January 7, 1989 AD.  Strictly speaking, the first six days
 * of that year were in the Showa era, e.g. "January 6, 64 Showa", while the rest
 * of the year was in the Heisei era, e.g. "January 7, 1 Heisei".  This class
 * handles this distinction correctly when computing dates.  However, in lenient
 * mode either form of date is acceptable as input. 
 * <p>
 * In modern times, eras have started on January 8, 1868 AD, Gregorian (Meiji),
 * July 30, 1912 (Taisho), December 25, 1926 (Showa), and January 7, 1989 (Heisei).  Constants
 * for these eras, suitable for use in the <code>UCAL_ERA</code> field, are provided
 * in this class.  Note that the <em>number</em> used for each era is more or
 * less arbitrary.  Currently, the era starting in 645 AD is era #0; however this
 * may change in the future.  Use the predefined constants rather than using actual,
 * absolute numbers.
 * <p>
 * Since ICU4C 63, start date of each era is imported from CLDR. CLDR era data
 * may contain tentative era in near future with placeholder names. By default,
 * such era data is not enabled. ICU4C users who want to test the behavior of
 * the future era can enable this one of following settings (in the priority
 * order):
 * <ol>
 * <li>Environment variable <code>ICU_ENABLE_TENTATIVE_ERA=true</code>.</li>
 * </nl>
 * @internal
 */
class JapaneseCalendar : public GregorianCalendar {
public:

    /**
     * Check environment variable. 
     * @internal
     */
    U_I18N_API static UBool U_EXPORT2 enableTentativeEra(void);

    /**
     * Useful constants for JapaneseCalendar.
     * Exported for use by test code.
     * @internal
     */
    U_I18N_API static uint32_t U_EXPORT2 getCurrentEra(void); // the current era

    /**
     * Constructs a JapaneseCalendar based on the current time in the default time zone
     * with the given locale.
     *
     * @param aLocale  The given locale.
     * @param success  Indicates the status of JapaneseCalendar object construction.
     *                 Returns U_ZERO_ERROR if constructed successfully.
     * @stable ICU 2.0
     */
    JapaneseCalendar(const Locale& aLocale, UErrorCode& success);


    /**
     * Destructor
     * @internal
     */
    virtual ~JapaneseCalendar();

    /**
     * Copy constructor
     * @param source    the object to be copied.
     * @internal
     */
    JapaneseCalendar(const JapaneseCalendar& source);

    /**
     * Default assignment operator
     * @param right    the object to be copied.
     * @internal
     */
    JapaneseCalendar& operator=(const JapaneseCalendar& right);

    /**
     * Create and return a polymorphic copy of this calendar.
     * @return    return a polymorphic copy of this calendar.
     * @internal
     */
    virtual JapaneseCalendar* clone() const override;

    /**
     * Return the extended year defined by the current fields.  In the 
     * Japanese calendar case, this is equal to the equivalent extended Gregorian year.
     * @internal
     */
    virtual int32_t handleGetExtendedYear() override;

    /**
     * Return the maximum value that this field could have, given the current date.
     * @internal
     */
    virtual int32_t getActualMaximum(UCalendarDateFields field, UErrorCode& status) const override;


public:
    /**
     * Override Calendar Returns a unique class ID POLYMORPHICALLY. Pure virtual
     * override. This method is to implement a simple version of RTTI, since not all C++
     * compilers support genuine RTTI. Polymorphic operator==() and clone() methods call
     * this method.
     *
     * @return   The class ID for this object. All objects of a given class have the
     *           same class ID. Objects of other classes have different class IDs.
     * @internal
     */
    virtual UClassID getDynamicClassID(void) const override;

    /**
     * Return the class ID for this class. This is useful only for comparing to a return
     * value from getDynamicClassID(). For example:
     *
     *      Base* polymorphic_pointer = createPolymorphicObject();
     *      if (polymorphic_pointer->getDynamicClassID() ==
     *          Derived::getStaticClassID()) ...
     *
     * @return   The class ID for all objects of this class.
     * @internal
     */
    U_I18N_API static UClassID U_EXPORT2 getStaticClassID(void);

    /**
     * return the calendar type, "japanese".
     *
     * @return calendar type
     * @internal
     */
    virtual const char * getType() const override;

    /**
     * @return false - no default century in Japanese
     * @internal 
     */
    virtual UBool haveDefaultCentury() const override;

    /**
     * Not used - no default century.
     * @internal
     */
    virtual UDate defaultCenturyStart() const override;
    /**
     * Not used - no default century.
     * @internal
     */
    virtual int32_t defaultCenturyStartYear() const override;

private:
    JapaneseCalendar(); // default constructor not implemented

protected:
    /** 
     * Calculate the era for internal computation
     * @internal
     */
    virtual int32_t internalGetEra() const override;

    /**
     * Compute fields from the JD
     * @internal
     */
    virtual void handleComputeFields(int32_t julianDay, UErrorCode& status) override;

    /**
     * Calculate the limit for a specified type of limit and field
     * @internal
     */
    virtual int32_t handleGetLimit(UCalendarDateFields field, ELimitType limitType) const override;

    /***
     * Called by computeJulianDay.  Returns the default month (0-based) for the year,
     * taking year and era into account.  Will return the first month of the given era, if 
     * the current year is an ascension year.
     * @param eyear the extended year
     * @internal
     */
    virtual int32_t getDefaultMonthInYear(int32_t eyear) override;

    /***
     * Called by computeJulianDay.  Returns the default day (1-based) for the month,
     * taking currently-set year and era into account.  Will return the first day of the given
     * era, if the current month is an ascension year and month.
     * @param eyear the extended year
     * @param mon the month in the year
     * @internal
     */
    virtual int32_t getDefaultDayInMonth(int32_t eyear, int32_t month) override;
};

U_NAMESPACE_END

#endif /* #if !UCONFIG_NO_FORMATTING */

#endif
//eof