1 /*
   2  * Copyright (c) 2010, 2013, 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 static java.util.GregorianCalendar.*;
  30 
  31 /**
  32  * {@code CalendarBuilder} keeps field-value pairs for setting
  33  * the calendar fields of the given {@code Calendar}. It has the
  34  * {@link Calendar#FIELD_COUNT FIELD_COUNT}-th field for the week year
  35  * support. Also {@code ISO_DAY_OF_WEEK} is used to specify
  36  * {@code DAY_OF_WEEK} in the ISO day of week numbering.
  37  *
  38  * <p>{@code CalendarBuilder} retains the semantic of the pseudo
  39  * timestamp for fields. {@code CalendarBuilder} uses a single
  40  * int array combining fields[] and stamp[] of {@code Calendar}.
  41  *
  42  * @author Masayoshi Okutsu
  43  */
  44 class CalendarBuilder {
  45     /*
  46      * Pseudo time stamp constants used in java.util.Calendar
  47      */
  48     private static final int UNSET = 0;
  49     private static final int COMPUTED = 1;
  50     private static final int MINIMUM_USER_STAMP = 2;
  51 
  52     private static final int MAX_FIELD = FIELD_COUNT + 1;
  53 
  54     public static final int WEEK_YEAR = FIELD_COUNT;
  55     public static final int ISO_DAY_OF_WEEK = 1000; // pseudo field index
  56 
  57     // stamp[] (lower half) and field[] (upper half) combined
  58     private final int[] field;
  59     private int nextStamp;
  60     private int maxFieldIndex;
  61 
  62     CalendarBuilder() {
  63         field = new int[MAX_FIELD * 2];
  64         nextStamp = MINIMUM_USER_STAMP;
  65         maxFieldIndex = -1;
  66     }
  67 
  68     CalendarBuilder set(int index, int value) {
  69         if (index == ISO_DAY_OF_WEEK) {
  70             index = DAY_OF_WEEK;
  71             value = toCalendarDayOfWeek(value);
  72         }
  73         field[index] = nextStamp++;
  74         field[MAX_FIELD + index] = value;
  75         if (index > maxFieldIndex && index < FIELD_COUNT) {
  76             maxFieldIndex = index;
  77         }
  78         return this;
  79     }
  80 
  81     CalendarBuilder addYear(int value) {
  82         field[MAX_FIELD + YEAR] += value;
  83         field[MAX_FIELD + WEEK_YEAR] += value;
  84         return this;
  85     }
  86 
  87     boolean isSet(int index) {
  88         if (index == ISO_DAY_OF_WEEK) {
  89             index = DAY_OF_WEEK;
  90         }
  91         return field[index] > UNSET;
  92     }
  93 
  94     CalendarBuilder clear(int index) {
  95         if (index == ISO_DAY_OF_WEEK) {
  96             index = DAY_OF_WEEK;
  97         }
  98         field[index] = UNSET;
  99         field[MAX_FIELD + index] = 0;
 100         return this;
 101     }
 102 
 103     Calendar establish(Calendar cal) {
 104         boolean weekDate = isSet(WEEK_YEAR)
 105                             && field[WEEK_YEAR] > field[YEAR];
 106         if (weekDate && !cal.isWeekDateSupported()) {
 107             // Use YEAR instead
 108             if (!isSet(YEAR)) {
 109                 set(YEAR, field[MAX_FIELD + WEEK_YEAR]);
 110             }
 111             weekDate = false;
 112         }
 113 
 114         cal.clear();
 115         // Set the fields from the min stamp to the max stamp so that
 116         // the field resolution works in the Calendar.
 117         for (int stamp = MINIMUM_USER_STAMP; stamp < nextStamp; stamp++) {
 118             for (int index = 0; index <= maxFieldIndex; index++) {
 119                 if (field[index] == stamp) {
 120                     cal.set(index, field[MAX_FIELD + index]);
 121                     break;
 122                 }
 123             }
 124         }
 125 
 126         if (weekDate) {
 127             int weekOfYear = isSet(WEEK_OF_YEAR) ? field[MAX_FIELD + WEEK_OF_YEAR] : 1;
 128             int dayOfWeek = isSet(DAY_OF_WEEK) ?
 129                                 field[MAX_FIELD + DAY_OF_WEEK] : cal.getFirstDayOfWeek();
 130             if (!isValidDayOfWeek(dayOfWeek) && cal.isLenient()) {
 131                 if (dayOfWeek >= 8) {
 132                     dayOfWeek--;
 133                     weekOfYear += dayOfWeek / 7;
 134                     dayOfWeek = (dayOfWeek % 7) + 1;
 135                 } else {
 136                     while (dayOfWeek <= 0) {
 137                         dayOfWeek += 7;
 138                         weekOfYear--;
 139                     }
 140                 }
 141                 dayOfWeek = toCalendarDayOfWeek(dayOfWeek);
 142             }
 143             cal.setWeekDate(field[MAX_FIELD + WEEK_YEAR], weekOfYear, dayOfWeek);
 144         }
 145         return cal;
 146     }
 147 
 148     public String toString() {
 149         StringBuilder sb = new StringBuilder();
 150         sb.append("CalendarBuilder:[");
 151         for (int i = 0; i < field.length; i++) {
 152             if (isSet(i)) {
 153                 sb.append(i).append('=').append(field[MAX_FIELD + i]).append(',');
 154             }
 155         }
 156         int lastIndex = sb.length() - 1;
 157         if (sb.charAt(lastIndex) == ',') {
 158             sb.setLength(lastIndex);
 159         }
 160         sb.append(']');
 161         return sb.toString();
 162     }
 163 
 164     static int toISODayOfWeek(int calendarDayOfWeek) {
 165         return calendarDayOfWeek == SUNDAY ? 7 : calendarDayOfWeek - 1;
 166     }
 167 
 168     static int toCalendarDayOfWeek(int isoDayOfWeek) {
 169         if (!isValidDayOfWeek(isoDayOfWeek)) {
 170             // adjust later for lenient mode
 171             return isoDayOfWeek;
 172         }
 173         return isoDayOfWeek == 7 ? SUNDAY : isoDayOfWeek + 1;
 174     }
 175 
 176     static boolean isValidDayOfWeek(int dayOfWeek) {
 177         return dayOfWeek > 0 && dayOfWeek <= 7;
 178     }
 179 }