1 /*
   2  * Copyright (c) 2000, 2010, 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 sun.util;
  27 
  28 import java.io.IOException;
  29 import java.io.ObjectInputStream;
  30 import java.util.Calendar;
  31 import java.util.GregorianCalendar;
  32 import java.util.HashMap;
  33 import java.util.Locale;
  34 import java.util.Map;
  35 import java.util.ResourceBundle;
  36 import java.util.TimeZone;
  37 import sun.util.resources.LocaleData;
  38 
  39 public class BuddhistCalendar extends GregorianCalendar {
  40 
  41 //////////////////
  42 // Class Variables
  43 //////////////////
  44 
  45     private static final long serialVersionUID = -8527488697350388578L;
  46 
  47     private static final int BUDDHIST_YEAR_OFFSET = 543;
  48 
  49 ///////////////
  50 // Constructors
  51 ///////////////
  52 
  53     /**
  54      * Constructs a default BuddhistCalendar using the current time
  55      * in the default time zone with the default locale.
  56      */
  57     public BuddhistCalendar() {
  58         super();
  59     }
  60 
  61     /**
  62      * Constructs a BuddhistCalendar based on the current time
  63      * in the given time zone with the default locale.
  64      * @param zone the given time zone.
  65      */
  66     public BuddhistCalendar(TimeZone zone) {
  67         super(zone);
  68     }
  69 
  70     /**
  71      * Constructs a BuddhistCalendar based on the current time
  72      * in the default time zone with the given locale.
  73      * @param aLocale the given locale.
  74      */
  75     public BuddhistCalendar(Locale aLocale) {
  76         super(aLocale);
  77     }
  78 
  79     /**
  80      * Constructs a BuddhistCalendar based on the current time
  81      * in the given time zone with the given locale.
  82      * @param zone the given time zone.
  83      * @param aLocale the given locale.
  84      */
  85     public BuddhistCalendar(TimeZone zone, Locale aLocale) {
  86         super(zone, aLocale);
  87     }
  88 
  89 /////////////////
  90 // Public methods
  91 /////////////////
  92 
  93     /**
  94      * Compares this BuddhistCalendar to an object reference.
  95      * @param obj the object reference with which to compare
  96      * @return true if this object is equal to <code>obj</code>; false otherwise
  97      */
  98     public boolean equals(Object obj) {
  99         return obj instanceof BuddhistCalendar
 100             && super.equals(obj);
 101     }
 102 
 103     /**
 104      * Override hashCode.
 105      * Generates the hash code for the BuddhistCalendar object
 106      */
 107     public int hashCode() {
 108         return super.hashCode() ^ BUDDHIST_YEAR_OFFSET;
 109     }
 110 
 111     /**
 112      * Gets the value for a given time field.
 113      * @param field the given time field.
 114      * @return the value for the given time field.
 115      */
 116     public int get(int field)
 117     {
 118         if (field == YEAR) {
 119             return super.get(field) + yearOffset;
 120         }
 121         return super.get(field);
 122     }
 123 
 124     /**
 125      * Sets the time field with the given value.
 126      * @param field the given time field.
 127      * @param value the value to be set for the given time field.
 128      */
 129     public void set(int field, int value)
 130     {
 131         if (field == YEAR) {
 132             super.set(field, value - yearOffset);
 133         } else {
 134             super.set(field, value);
 135         }
 136     }
 137 
 138     /**
 139      * Adds the specified (signed) amount of time to the given time field.
 140      * @param field the time field.
 141      * @param amount the amount of date or time to be added to the field.
 142      */
 143     public void add(int field, int amount)
 144     {
 145         int savedYearOffset = yearOffset;
 146         // To let the superclass calculate date-time values correctly,
 147         // temporarily make this GregorianCalendar.
 148         yearOffset = 0;
 149         try {
 150             super.add(field, amount);
 151         } finally {
 152             yearOffset = savedYearOffset;
 153         }
 154     }
 155 
 156     /**
 157      * Add to field a signed amount without changing larger fields.
 158      * A negative roll amount means to subtract from field without changing
 159      * larger fields.
 160      * @param field the time field.
 161      * @param amount the signed amount to add to <code>field</code>.
 162      */
 163     public void roll(int field, int amount)
 164     {
 165         int savedYearOffset = yearOffset;
 166         // To let the superclass calculate date-time values correctly,
 167         // temporarily make this GregorianCalendar.
 168         yearOffset = 0;
 169         try {
 170             super.roll(field, amount);
 171         } finally {
 172             yearOffset = savedYearOffset;
 173         }
 174     }
 175 
 176     public String getDisplayName(int field, int style, Locale locale) {
 177         if (field != ERA) {
 178             return super.getDisplayName(field, style, locale);
 179         }
 180 
 181         // Handle Thai BuddhistCalendar specific era names
 182         if (field < 0 || field >= fields.length ||
 183             style < SHORT || style > LONG) {
 184             throw new IllegalArgumentException();
 185         }
 186         if (locale == null) {
 187             throw new NullPointerException();
 188         }
 189         ResourceBundle rb = LocaleData.getDateFormatData(locale);
 190         String[] eras = rb.getStringArray(getKey(style));
 191         return eras[get(field)];
 192     }
 193 
 194     public Map<String,Integer> getDisplayNames(int field, int style, Locale locale) {
 195         if (field != ERA) {
 196             return super.getDisplayNames(field, style, locale);
 197         }
 198 
 199         // Handle Thai BuddhistCalendar specific era names
 200         if (field < 0 || field >= fields.length ||
 201             style < ALL_STYLES || style > LONG) {
 202             throw new IllegalArgumentException();
 203         }
 204         if (locale == null) {
 205             throw new NullPointerException();
 206         }
 207         // ALL_STYLES
 208         if (style == ALL_STYLES) {
 209             Map<String,Integer> shortNames = getDisplayNamesImpl(field, SHORT, locale);
 210             Map<String,Integer> longNames = getDisplayNamesImpl(field, LONG, locale);
 211             if (shortNames == null) {
 212                 return longNames;
 213             }
 214             if (longNames != null) {
 215                 shortNames.putAll(longNames);
 216             }
 217             return shortNames;
 218         }
 219 
 220         // SHORT or LONG
 221         return getDisplayNamesImpl(field, style, locale);
 222     }
 223 
 224     private Map<String,Integer> getDisplayNamesImpl(int field, int style, Locale locale) {
 225         ResourceBundle rb = LocaleData.getDateFormatData(locale);
 226         String[] eras = rb.getStringArray(getKey(style));
 227         Map<String,Integer> map = new HashMap<String,Integer>(4);
 228         for (int i = 0; i < eras.length; i++) {
 229             map.put(eras[i], i);
 230         }
 231         return map;
 232     }
 233 
 234     private String getKey(int style) {
 235         StringBuilder key = new StringBuilder();
 236         key.append(BuddhistCalendar.class.getName());
 237         if (style == SHORT) {
 238             key.append(".short");
 239         }
 240         key.append(".Eras");
 241         return key.toString();
 242     }
 243 
 244     /**
 245      * Returns the maximum value that this field could have, given the
 246      * current date.  For example, with the date "Feb 3, 2540" and the
 247      * <code>DAY_OF_MONTH</code> field, the actual maximum is 28; for
 248      * "Feb 3, 2539" it is 29.
 249      *
 250      * @param field the field to determine the maximum of
 251      * @return the maximum of the given field for the current date of this Calendar
 252      */
 253     public int getActualMaximum(int field) {
 254         int savedYearOffset = yearOffset;
 255         // To let the superclass calculate date-time values correctly,
 256         // temporarily make this GregorianCalendar.
 257         yearOffset = 0;
 258         try {
 259             return super.getActualMaximum(field);
 260         } finally {
 261             yearOffset = savedYearOffset;
 262         }
 263     }
 264 
 265     public String toString() {
 266         // The super class produces a String with the Gregorian year
 267         // value (or '?')
 268         String s = super.toString();
 269         // If the YEAR field is UNSET, then return the Gregorian string.
 270         if (!isSet(YEAR)) {
 271             return s;
 272         }
 273 
 274         final String yearField = "YEAR=";
 275         int p = s.indexOf(yearField);
 276         // If the string doesn't include the year value for some
 277         // reason, then return the Gregorian string.
 278         if (p == -1) {
 279             return s;
 280         }
 281         p += yearField.length();
 282         StringBuilder sb = new StringBuilder(s.substring(0, p));
 283         // Skip the year number
 284         while (Character.isDigit(s.charAt(p++)))
 285             ;
 286         int year = internalGet(YEAR) + BUDDHIST_YEAR_OFFSET;
 287         sb.append(year).append(s.substring(p - 1));
 288         return sb.toString();
 289     }
 290 
 291     private transient int yearOffset = BUDDHIST_YEAR_OFFSET;
 292 
 293     private void readObject(ObjectInputStream stream)
 294         throws IOException, ClassNotFoundException {
 295         stream.defaultReadObject();
 296         yearOffset = BUDDHIST_YEAR_OFFSET;
 297     }
 298 }