1 /*
   2  * Copyright (c) 2010, 2014, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  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 
  63     CalendarBuilder() {
  64         field = new int[MAX_FIELD * 2];
  65         nextStamp = MINIMUM_USER_STAMP;
  66         maxFieldIndex = -1;
  67     }
  68 
  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 
  82     CalendarBuilder addYear(int value) {
  83         field[MAX_FIELD + YEAR] += value;
  84         field[MAX_FIELD + WEEK_YEAR] += value;
  85         return this;
  86     }
  87 
  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 
  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 
 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 
 149     public String toString() {
 150         StringJoiner sj = new StringJoiner(",", "CalendarBuilder:[", "]");
 151         for (int i = 0; i < field.length; i++) {
 152             if (isSet(i)) {
 153                 sj.add(i + "=" + field[MAX_FIELD + i]);
 154             }
 155         }
 156         return sj.toString();
 157     }
 158 
 159     static int toISODayOfWeek(int calendarDayOfWeek) {
 160         return calendarDayOfWeek == SUNDAY ? 7 : calendarDayOfWeek - 1;
 161     }
 162 
 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 
 171     static boolean isValidDayOfWeek(int dayOfWeek) {
 172         return dayOfWeek > 0 && dayOfWeek <= 7;
 173     }
 174 }