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25 
26 package java.text;
27 
28 import java.util.Calendar;
29 import java.util.StringJoiner;
30 import static java.util.GregorianCalendar.*;
31 
32 /**
33  * {@code CalendarBuilder} keeps field-value pairs for setting
34  * the calendar fields of the given {@code Calendar}. It has the
35  * {@link Calendar#FIELD_COUNT FIELD_COUNT}-th field for the week year
36  * support. Also {@code ISO_DAY_OF_WEEK} is used to specify
37  * {@code DAY_OF_WEEK} in the ISO day of week numbering.
38  *
39  * <p>{@code CalendarBuilder} retains the semantic of the pseudo
40  * timestamp for fields. {@code CalendarBuilder} uses a single
41  * int array combining fields[] and stamp[] of {@code Calendar}.
42  *
43  * @author Masayoshi Okutsu
44  */
45 class CalendarBuilder {
46     /*
47      * Pseudo time stamp constants used in java.util.Calendar
48      */
49     private static final int UNSET = 0;
50     private static final int COMPUTED = 1;
51     private static final int MINIMUM_USER_STAMP = 2;
52 
53     private static final int MAX_FIELD = FIELD_COUNT + 1;
54 
55     public static final int WEEK_YEAR = FIELD_COUNT;
56     public static final int ISO_DAY_OF_WEEK = 1000; // pseudo field index
57 
58     // stamp[] (lower half) and field[] (upper half) combined
59     private final int[] field;
60     private int nextStamp;
61     private int maxFieldIndex;
62 
CalendarBuilder()63     CalendarBuilder() {
64         field = new int[MAX_FIELD * 2];
65         nextStamp = MINIMUM_USER_STAMP;
66         maxFieldIndex = -1;
67     }
68 
set(int index, int value)69     CalendarBuilder set(int index, int value) {
70         if (index == ISO_DAY_OF_WEEK) {
71             index = DAY_OF_WEEK;
72             value = toCalendarDayOfWeek(value);
73         }
74         field[index] = nextStamp++;
75         field[MAX_FIELD + index] = value;
76         if (index > maxFieldIndex && index < FIELD_COUNT) {
77             maxFieldIndex = index;
78         }
79         return this;
80     }
81 
addYear(int value)82     CalendarBuilder addYear(int value) {
83         field[MAX_FIELD + YEAR] += value;
84         field[MAX_FIELD + WEEK_YEAR] += value;
85         return this;
86     }
87 
isSet(int index)88     boolean isSet(int index) {
89         if (index == ISO_DAY_OF_WEEK) {
90             index = DAY_OF_WEEK;
91         }
92         return field[index] > UNSET;
93     }
94 
clear(int index)95     CalendarBuilder clear(int index) {
96         if (index == ISO_DAY_OF_WEEK) {
97             index = DAY_OF_WEEK;
98         }
99         field[index] = UNSET;
100         field[MAX_FIELD + index] = 0;
101         return this;
102     }
103 
establish(Calendar cal)104     Calendar establish(Calendar cal) {
105         boolean weekDate = isSet(WEEK_YEAR)
106                             && field[WEEK_YEAR] > field[YEAR];
107         if (weekDate && !cal.isWeekDateSupported()) {
108             // Use YEAR instead
109             if (!isSet(YEAR)) {
110                 set(YEAR, field[MAX_FIELD + WEEK_YEAR]);
111             }
112             weekDate = false;
113         }
114 
115         cal.clear();
116         // Set the fields from the min stamp to the max stamp so that
117         // the field resolution works in the Calendar.
118         for (int stamp = MINIMUM_USER_STAMP; stamp < nextStamp; stamp++) {
119             for (int index = 0; index <= maxFieldIndex; index++) {
120                 if (field[index] == stamp) {
121                     cal.set(index, field[MAX_FIELD + index]);
122                     break;
123                 }
124             }
125         }
126 
127         if (weekDate) {
128             int weekOfYear = isSet(WEEK_OF_YEAR) ? field[MAX_FIELD + WEEK_OF_YEAR] : 1;
129             int dayOfWeek = isSet(DAY_OF_WEEK) ?
130                                 field[MAX_FIELD + DAY_OF_WEEK] : cal.getFirstDayOfWeek();
131             if (!isValidDayOfWeek(dayOfWeek) && cal.isLenient()) {
132                 if (dayOfWeek >= 8) {
133                     dayOfWeek--;
134                     weekOfYear += dayOfWeek / 7;
135                     dayOfWeek = (dayOfWeek % 7) + 1;
136                 } else {
137                     while (dayOfWeek <= 0) {
138                         dayOfWeek += 7;
139                         weekOfYear--;
140                     }
141                 }
142                 dayOfWeek = toCalendarDayOfWeek(dayOfWeek);
143             }
144             cal.setWeekDate(field[MAX_FIELD + WEEK_YEAR], weekOfYear, dayOfWeek);
145         }
146         return cal;
147     }
148 
toString()149     public String toString() {
150         StringJoiner sj = new StringJoiner(",", "CalendarBuilder:[", "]");
151         for (int i = 0; i < MAX_FIELD; i++) {
152             if (isSet(i)) {
153                 sj.add(i + "=" + field[i] + ":" + field[MAX_FIELD + i]);
154             }
155         }
156         return sj.toString();
157     }
158 
toISODayOfWeek(int calendarDayOfWeek)159     static int toISODayOfWeek(int calendarDayOfWeek) {
160         return calendarDayOfWeek == SUNDAY ? 7 : calendarDayOfWeek - 1;
161     }
162 
toCalendarDayOfWeek(int isoDayOfWeek)163     static int toCalendarDayOfWeek(int isoDayOfWeek) {
164         if (!isValidDayOfWeek(isoDayOfWeek)) {
165             // adjust later for lenient mode
166             return isoDayOfWeek;
167         }
168         return isoDayOfWeek == 7 ? SUNDAY : isoDayOfWeek + 1;
169     }
170 
isValidDayOfWeek(int dayOfWeek)171     static boolean isValidDayOfWeek(int dayOfWeek) {
172         return dayOfWeek > 0 && dayOfWeek <= 7;
173     }
174 }
175