1 /*
2  * Copyright (C) 2006 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package android.text.format;
18 
19 import android.compat.annotation.UnsupportedAppUsage;
20 import android.content.Context;
21 import android.content.res.Configuration;
22 import android.content.res.Resources;
23 import android.icu.text.DateFormatSymbols;
24 import android.icu.text.MeasureFormat;
25 import android.icu.text.MeasureFormat.FormatWidth;
26 import android.icu.util.Measure;
27 import android.icu.util.MeasureUnit;
28 import android.os.Build;
29 
30 import com.android.internal.R;
31 
32 import java.io.IOException;
33 import java.time.Instant;
34 import java.time.LocalDateTime;
35 import java.time.ZoneId;
36 import java.util.Calendar;
37 import java.util.Date;
38 import java.util.Formatter;
39 import java.util.GregorianCalendar;
40 import java.util.Locale;
41 import java.util.TimeZone;
42 
43 /**
44  * This class contains various date-related utilities for creating text for things like
45  * elapsed time and date ranges, strings for days of the week and months, and AM/PM text etc.
46  */
47 public class DateUtils
48 {
49     private static final Object sLock = new Object();
50     private static Configuration sLastConfig;
51     private static String sElapsedFormatMMSS;
52     private static String sElapsedFormatHMMSS;
53 
54     public static final long SECOND_IN_MILLIS = 1000;
55     public static final long MINUTE_IN_MILLIS = SECOND_IN_MILLIS * 60;
56     public static final long HOUR_IN_MILLIS = MINUTE_IN_MILLIS * 60;
57     public static final long DAY_IN_MILLIS = HOUR_IN_MILLIS * 24;
58     public static final long WEEK_IN_MILLIS = DAY_IN_MILLIS * 7;
59     /**
60      * @deprecated Not all years have the same number of days, and this constant is actually the
61      * length of 364 days. Please use other date/time constructs such as
62      * {@link java.util.concurrent.TimeUnit}, {@link java.util.Calendar} or
63      * {@link java.time.Duration} instead.
64      */
65     @Deprecated
66     public static final long YEAR_IN_MILLIS = WEEK_IN_MILLIS * 52;
67 
68     // The following FORMAT_* symbols are used for specifying the format of
69     // dates and times in the formatDateRange method.
70     public static final int FORMAT_SHOW_TIME = 0x00001;
71     public static final int FORMAT_SHOW_WEEKDAY = 0x00002;
72     public static final int FORMAT_SHOW_YEAR = 0x00004;
73     public static final int FORMAT_NO_YEAR = 0x00008;
74     public static final int FORMAT_SHOW_DATE = 0x00010;
75     public static final int FORMAT_NO_MONTH_DAY = 0x00020;
76     @Deprecated
77     public static final int FORMAT_12HOUR = 0x00040;
78     @Deprecated
79     public static final int FORMAT_24HOUR = 0x00080;
80     @Deprecated
81     public static final int FORMAT_CAP_AMPM = 0x00100;
82     public static final int FORMAT_NO_NOON = 0x00200;
83     @Deprecated
84     public static final int FORMAT_CAP_NOON = 0x00400;
85     public static final int FORMAT_NO_MIDNIGHT = 0x00800;
86     @Deprecated
87     public static final int FORMAT_CAP_MIDNIGHT = 0x01000;
88     /**
89      * @deprecated Use
90      * {@link #formatDateRange(Context, Formatter, long, long, int, String) formatDateRange}
91      * and pass in {@link Time#TIMEZONE_UTC Time.TIMEZONE_UTC} for the timeZone instead.
92      */
93     @Deprecated
94     public static final int FORMAT_UTC = 0x02000;
95     public static final int FORMAT_ABBREV_TIME = 0x04000;
96     public static final int FORMAT_ABBREV_WEEKDAY = 0x08000;
97     public static final int FORMAT_ABBREV_MONTH = 0x10000;
98     public static final int FORMAT_NUMERIC_DATE = 0x20000;
99     public static final int FORMAT_ABBREV_RELATIVE = 0x40000;
100     public static final int FORMAT_ABBREV_ALL = 0x80000;
101     @Deprecated
102     public static final int FORMAT_CAP_NOON_MIDNIGHT = (FORMAT_CAP_NOON | FORMAT_CAP_MIDNIGHT);
103     @Deprecated
104     public static final int FORMAT_NO_NOON_MIDNIGHT = (FORMAT_NO_NOON | FORMAT_NO_MIDNIGHT);
105 
106     // Date and time format strings that are constant and don't need to be
107     // translated.
108     /**
109      * This is not actually the preferred 24-hour date format in all locales.
110      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
111      */
112     @Deprecated
113     public static final String HOUR_MINUTE_24 = "%H:%M";
114     public static final String MONTH_FORMAT = "%B";
115     /**
116      * This is not actually a useful month name in all locales.
117      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
118      */
119     @Deprecated
120     public static final String ABBREV_MONTH_FORMAT = "%b";
121     public static final String NUMERIC_MONTH_FORMAT = "%m";
122     public static final String MONTH_DAY_FORMAT = "%-d";
123     public static final String YEAR_FORMAT = "%Y";
124     public static final String YEAR_FORMAT_TWO_DIGITS = "%g";
125     public static final String WEEKDAY_FORMAT = "%A";
126     public static final String ABBREV_WEEKDAY_FORMAT = "%a";
127 
128     /** @deprecated Do not use. */
129     @Deprecated
130     public static final int[] sameYearTable = null;
131 
132     /** @deprecated Do not use. */
133     @Deprecated
134     public static final int[] sameMonthTable = null;
135 
136     /**
137      * Request the full spelled-out name. For use with the 'abbrev' parameter of
138      * {@link #getDayOfWeekString} and {@link #getMonthString}.
139      *
140      * @more <p>
141      *       e.g. "Sunday" or "January"
142      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
143      */
144     @Deprecated
145     public static final int LENGTH_LONG = 10;
146 
147     /**
148      * Request an abbreviated version of the name. For use with the 'abbrev'
149      * parameter of {@link #getDayOfWeekString} and {@link #getMonthString}.
150      *
151      * @more <p>
152      *       e.g. "Sun" or "Jan"
153      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
154      */
155     @Deprecated
156     public static final int LENGTH_MEDIUM = 20;
157 
158     /**
159      * Request a shorter abbreviated version of the name.
160      * For use with the 'abbrev' parameter of {@link #getDayOfWeekString} and {@link #getMonthString}.
161      * @more
162      * <p>e.g. "Su" or "Jan"
163      * <p>In most languages, the results returned for LENGTH_SHORT will be the same as
164      * the results returned for {@link #LENGTH_MEDIUM}.
165      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
166      */
167     @Deprecated
168     public static final int LENGTH_SHORT = 30;
169 
170     /**
171      * Request an even shorter abbreviated version of the name.
172      * Do not use this.  Currently this will always return the same result
173      * as {@link #LENGTH_SHORT}.
174      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
175      */
176     @Deprecated
177     public static final int LENGTH_SHORTER = 40;
178 
179     /**
180      * Request an even shorter abbreviated version of the name.
181      * For use with the 'abbrev' parameter of {@link #getDayOfWeekString} and {@link #getMonthString}.
182      * @more
183      * <p>e.g. "S", "T", "T" or "J"
184      * <p>In some languages, the results returned for LENGTH_SHORTEST will be the same as
185      * the results returned for {@link #LENGTH_SHORT}.
186      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
187      */
188     @Deprecated
189     public static final int LENGTH_SHORTEST = 50;
190 
191     /**
192      * Return a string for the day of the week.
193      * @param dayOfWeek One of {@link Calendar#SUNDAY Calendar.SUNDAY},
194      *               {@link Calendar#MONDAY Calendar.MONDAY}, etc.
195      * @param abbrev One of {@link #LENGTH_LONG}, {@link #LENGTH_SHORT},
196      *               {@link #LENGTH_MEDIUM}, or {@link #LENGTH_SHORTEST}.
197      *               Note that in most languages, {@link #LENGTH_SHORT}
198      *               will return the same as {@link #LENGTH_MEDIUM}.
199      *               Undefined lengths will return {@link #LENGTH_MEDIUM}
200      *               but may return something different in the future.
201      * @throws IndexOutOfBoundsException if the dayOfWeek is out of bounds.
202      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
203      */
204     @Deprecated
getDayOfWeekString(int dayOfWeek, int abbrev)205     public static String getDayOfWeekString(int dayOfWeek, int abbrev) {
206         DateFormatSymbols dfs = DateFormatSymbols.getInstance();
207         final int width;
208         switch (abbrev) {
209             case LENGTH_LONG:
210                 width = DateFormatSymbols.WIDE;
211                 break;
212             case LENGTH_SHORTEST:
213                 width = DateFormatSymbols.NARROW;
214                 break;
215             case LENGTH_MEDIUM:
216             case LENGTH_SHORT:   // TODO
217             case LENGTH_SHORTER: // TODO
218             default:
219                 width = DateFormatSymbols.ABBREVIATED;
220                 break;
221         }
222         return dfs.getWeekdays(DateFormatSymbols.FORMAT, width)[dayOfWeek];
223     }
224 
225     /**
226      * Return a localized string for AM or PM.
227      * @param ampm Either {@link Calendar#AM Calendar.AM} or {@link Calendar#PM Calendar.PM}.
228      * @throws IndexOutOfBoundsException if the ampm is out of bounds.
229      * @return Localized version of "AM" or "PM".
230      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
231      */
232     @Deprecated
getAMPMString(int ampm)233     public static String getAMPMString(int ampm) {
234         String[] amPm = DateFormat.getIcuDateFormatSymbols(Locale.getDefault()).getAmPmStrings();
235         return amPm[ampm - Calendar.AM];
236     }
237 
238     /**
239      * Return a localized string for the month of the year.
240      * @param month One of {@link Calendar#JANUARY Calendar.JANUARY},
241      *               {@link Calendar#FEBRUARY Calendar.FEBRUARY}, etc.
242      * @param abbrev One of {@link #LENGTH_LONG}, {@link #LENGTH_MEDIUM},
243      *               or {@link #LENGTH_SHORTEST}.
244      *               Undefined lengths will return {@link #LENGTH_MEDIUM}
245      *               but may return something different in the future.
246      * @return Localized month of the year.
247      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
248      */
249     @Deprecated
getMonthString(int month, int abbrev)250     public static String getMonthString(int month, int abbrev) {
251         DateFormatSymbols dfs = DateFormat.getIcuDateFormatSymbols(Locale.getDefault());
252         final int width;
253         switch (abbrev) {
254             case LENGTH_LONG:
255                 width = DateFormatSymbols.WIDE;
256                 break;
257             case LENGTH_SHORTEST:
258                 width = DateFormatSymbols.NARROW;
259                 break;
260             case LENGTH_MEDIUM:
261             case LENGTH_SHORT:
262             case LENGTH_SHORTER:
263             default:
264                 width = DateFormatSymbols.ABBREVIATED;
265                 break;
266         }
267         return dfs.getMonths(DateFormatSymbols.FORMAT, width)[month];
268     }
269 
270     /**
271      * Returns a string describing the elapsed time since startTime.
272      * <p>
273      * The minimum timespan to report is set to {@link #MINUTE_IN_MILLIS}.
274      * @param startTime some time in the past.
275      * @return a String object containing the elapsed time.
276      * @see #getRelativeTimeSpanString(long, long, long)
277      */
getRelativeTimeSpanString(long startTime)278     public static CharSequence getRelativeTimeSpanString(long startTime) {
279         return getRelativeTimeSpanString(startTime, System.currentTimeMillis(), MINUTE_IN_MILLIS);
280     }
281 
282     /**
283      * Returns a string describing 'time' as a time relative to 'now'.
284      * <p>
285      * Time spans in the past are formatted like "42 minutes ago".
286      * Time spans in the future are formatted like "In 42 minutes".
287      *
288      * @param time the time to describe, in milliseconds
289      * @param now the current time in milliseconds
290      * @param minResolution the minimum timespan to report. For example, a time 3 seconds in the
291      *     past will be reported as "0 minutes ago" if this is set to MINUTE_IN_MILLIS. Pass one of
292      *     0, MINUTE_IN_MILLIS, HOUR_IN_MILLIS, DAY_IN_MILLIS, WEEK_IN_MILLIS
293      */
getRelativeTimeSpanString(long time, long now, long minResolution)294     public static CharSequence getRelativeTimeSpanString(long time, long now, long minResolution) {
295         int flags = FORMAT_SHOW_DATE | FORMAT_SHOW_YEAR | FORMAT_ABBREV_MONTH;
296         return getRelativeTimeSpanString(time, now, minResolution, flags);
297     }
298 
299     /**
300      * Returns a string describing 'time' as a time relative to 'now'.
301      * <p>
302      * Time spans in the past are formatted like "42 minutes ago". Time spans in
303      * the future are formatted like "In 42 minutes".
304      * <p>
305      * Can use {@link #FORMAT_ABBREV_RELATIVE} flag to use abbreviated relative
306      * times, like "42 mins ago".
307      *
308      * @param time the time to describe, in milliseconds
309      * @param now the current time in milliseconds
310      * @param minResolution the minimum timespan to report. For example, a time
311      *            3 seconds in the past will be reported as "0 minutes ago" if
312      *            this is set to MINUTE_IN_MILLIS. Pass one of 0,
313      *            MINUTE_IN_MILLIS, HOUR_IN_MILLIS, DAY_IN_MILLIS,
314      *            WEEK_IN_MILLIS
315      * @param flags a bit mask of formatting options, such as
316      *            {@link #FORMAT_NUMERIC_DATE} or
317      *            {@link #FORMAT_ABBREV_RELATIVE}
318      */
getRelativeTimeSpanString(long time, long now, long minResolution, int flags)319     public static CharSequence getRelativeTimeSpanString(long time, long now, long minResolution,
320             int flags) {
321         return RelativeDateTimeFormatter.getRelativeTimeSpanString(Locale.getDefault(),
322                 TimeZone.getDefault(), time, now, minResolution, flags);
323     }
324 
325     /**
326      * Return string describing the elapsed time since startTime formatted like
327      * "[relative time/date], [time]".
328      * <p>
329      * Example output strings for the US date format.
330      * <ul>
331      * <li>3 min. ago, 10:15 AM</li>
332      * <li>Yesterday, 12:20 PM</li>
333      * <li>Dec 12, 4:12 AM</li>
334      * <li>11/14/2007, 8:20 AM</li>
335      * </ul>
336      *
337      * @param time some time in the past.
338      * @param minResolution the minimum elapsed time (in milliseconds) to report
339      *            when showing relative times. For example, a time 3 seconds in
340      *            the past will be reported as "0 minutes ago" if this is set to
341      *            {@link #MINUTE_IN_MILLIS}.
342      * @param transitionResolution the elapsed time (in milliseconds) at which
343      *            to stop reporting relative measurements. Elapsed times greater
344      *            than this resolution will default to normal date formatting.
345      *            For example, will transition from "7 days ago" to "Dec 12"
346      *            when using {@link #WEEK_IN_MILLIS}.
347      */
getRelativeDateTimeString(Context c, long time, long minResolution, long transitionResolution, int flags)348     public static CharSequence getRelativeDateTimeString(Context c, long time, long minResolution,
349             long transitionResolution, int flags) {
350         // Same reason as in formatDateRange() to explicitly indicate 12- or 24-hour format.
351         if ((flags & (FORMAT_SHOW_TIME | FORMAT_12HOUR | FORMAT_24HOUR)) == FORMAT_SHOW_TIME) {
352             flags |= DateFormat.is24HourFormat(c) ? FORMAT_24HOUR : FORMAT_12HOUR;
353         }
354 
355         return RelativeDateTimeFormatter.getRelativeDateTimeString(Locale.getDefault(),
356                 TimeZone.getDefault(), time, System.currentTimeMillis(), minResolution,
357                 transitionResolution, flags);
358     }
359 
initFormatStrings()360     private static void initFormatStrings() {
361         synchronized (sLock) {
362             initFormatStringsLocked();
363         }
364     }
365 
initFormatStringsLocked()366     private static void initFormatStringsLocked() {
367         Resources r = Resources.getSystem();
368         Configuration cfg = r.getConfiguration();
369         if (sLastConfig == null || !sLastConfig.equals(cfg)) {
370             sLastConfig = cfg;
371             sElapsedFormatMMSS = r.getString(com.android.internal.R.string.elapsed_time_short_format_mm_ss);
372             sElapsedFormatHMMSS = r.getString(com.android.internal.R.string.elapsed_time_short_format_h_mm_ss);
373         }
374     }
375 
376     /**
377      * Returns the given duration in a human-friendly format. For example,
378      * "4 minutes" or "1 second". Returns only the largest meaningful unit of time,
379      * from seconds up to hours.
380      *
381      * @hide
382      */
383     @UnsupportedAppUsage
formatDuration(long millis)384     public static CharSequence formatDuration(long millis) {
385         return formatDuration(millis, LENGTH_LONG);
386     }
387 
388     /**
389      * Returns the given duration in a human-friendly format. For example,
390      * "4 minutes" or "1 second". Returns only the largest meaningful unit of time,
391      * from seconds up to hours.
392      * <p>
393      * You can use abbrev to specify a preference for abbreviations (but note that some
394      * locales may not have abbreviations). Use LENGTH_LONG for the full spelling (e.g. "2 hours"),
395      * LENGTH_SHORT for the abbreviated spelling if available (e.g. "2 hr"), and LENGTH_SHORTEST for
396      * the briefest form available (e.g. "2h").
397      * @hide
398      */
399     @UnsupportedAppUsage(maxTargetSdk = Build.VERSION_CODES.R, trackingBug = 170729553)
formatDuration(long millis, int abbrev)400     public static CharSequence formatDuration(long millis, int abbrev) {
401         final FormatWidth width;
402         switch (abbrev) {
403             case LENGTH_LONG:
404                 width = FormatWidth.WIDE;
405                 break;
406             case LENGTH_SHORT:
407             case LENGTH_SHORTER:
408             case LENGTH_MEDIUM:
409                 width = FormatWidth.SHORT;
410                 break;
411             case LENGTH_SHORTEST:
412                 width = FormatWidth.NARROW;
413                 break;
414             default:
415                 width = FormatWidth.WIDE;
416         }
417         final MeasureFormat formatter = MeasureFormat.getInstance(Locale.getDefault(), width);
418         if (millis >= HOUR_IN_MILLIS) {
419             final int hours = (int) ((millis + 1800000) / HOUR_IN_MILLIS);
420             return formatter.format(new Measure(hours, MeasureUnit.HOUR));
421         } else if (millis >= MINUTE_IN_MILLIS) {
422             final int minutes = (int) ((millis + 30000) / MINUTE_IN_MILLIS);
423             return formatter.format(new Measure(minutes, MeasureUnit.MINUTE));
424         } else {
425             final int seconds = (int) ((millis + 500) / SECOND_IN_MILLIS);
426             return formatter.format(new Measure(seconds, MeasureUnit.SECOND));
427         }
428     }
429 
430     /**
431      * Formats an elapsed time in the form "MM:SS" or "H:MM:SS"
432      * for display on the call-in-progress screen.
433      * @param elapsedSeconds the elapsed time in seconds.
434      */
formatElapsedTime(long elapsedSeconds)435     public static String formatElapsedTime(long elapsedSeconds) {
436         return formatElapsedTime(null, elapsedSeconds);
437     }
438 
439     /**
440      * Formats an elapsed time in a format like "MM:SS" or "H:MM:SS" (using a form
441      * suited to the current locale), similar to that used on the call-in-progress
442      * screen.
443      *
444      * @param recycle {@link StringBuilder} to recycle, or null to use a temporary one.
445      * @param elapsedSeconds the elapsed time in seconds.
446      */
formatElapsedTime(StringBuilder recycle, long elapsedSeconds)447     public static String formatElapsedTime(StringBuilder recycle, long elapsedSeconds) {
448         // Break the elapsed seconds into hours, minutes, and seconds.
449         long hours = 0;
450         long minutes = 0;
451         long seconds = 0;
452         if (elapsedSeconds >= 3600) {
453             hours = elapsedSeconds / 3600;
454             elapsedSeconds -= hours * 3600;
455         }
456         if (elapsedSeconds >= 60) {
457             minutes = elapsedSeconds / 60;
458             elapsedSeconds -= minutes * 60;
459         }
460         seconds = elapsedSeconds;
461 
462         // Create a StringBuilder if we weren't given one to recycle.
463         // TODO: if we cared, we could have a thread-local temporary StringBuilder.
464         StringBuilder sb = recycle;
465         if (sb == null) {
466             sb = new StringBuilder(8);
467         } else {
468             sb.setLength(0);
469         }
470 
471         // Format the broken-down time in a locale-appropriate way.
472         // TODO: use icu4c when http://unicode.org/cldr/trac/ticket/3407 is fixed.
473         Formatter f = new Formatter(sb, Locale.getDefault());
474         initFormatStrings();
475         if (hours > 0) {
476             return f.format(sElapsedFormatHMMSS, hours, minutes, seconds).toString();
477         } else {
478             return f.format(sElapsedFormatMMSS, minutes, seconds).toString();
479         }
480     }
481 
482     /**
483      * Format a date / time such that if the then is on the same day as now, it shows
484      * just the time and if it's a different day, it shows just the date.
485      *
486      * <p>The parameters dateFormat and timeFormat should each be one of
487      * {@link java.text.DateFormat#DEFAULT},
488      * {@link java.text.DateFormat#FULL},
489      * {@link java.text.DateFormat#LONG},
490      * {@link java.text.DateFormat#MEDIUM}
491      * or
492      * {@link java.text.DateFormat#SHORT}
493      *
494      * @param then the date to format
495      * @param now the base time
496      * @param dateStyle how to format the date portion.
497      * @param timeStyle how to format the time portion.
498      */
formatSameDayTime(long then, long now, int dateStyle, int timeStyle)499     public static final CharSequence formatSameDayTime(long then, long now,
500             int dateStyle, int timeStyle) {
501         Calendar thenCal = new GregorianCalendar();
502         thenCal.setTimeInMillis(then);
503         Date thenDate = thenCal.getTime();
504         Calendar nowCal = new GregorianCalendar();
505         nowCal.setTimeInMillis(now);
506 
507         java.text.DateFormat f;
508 
509         if (thenCal.get(Calendar.YEAR) == nowCal.get(Calendar.YEAR)
510                 && thenCal.get(Calendar.MONTH) == nowCal.get(Calendar.MONTH)
511                 && thenCal.get(Calendar.DAY_OF_MONTH) == nowCal.get(Calendar.DAY_OF_MONTH)) {
512             f = java.text.DateFormat.getTimeInstance(timeStyle);
513         } else {
514             f = java.text.DateFormat.getDateInstance(dateStyle);
515         }
516         return f.format(thenDate);
517     }
518 
519     /**
520      * @return true if the supplied when is today else false
521      */
isToday(long when)522     public static boolean isToday(long when) {
523         return isSameDate(when, System.currentTimeMillis());
524     }
525 
isSameDate(long oneMillis, long twoMillis)526     private static boolean isSameDate(long oneMillis, long twoMillis) {
527         ZoneId zoneId = ZoneId.systemDefault();
528 
529         Instant oneInstant = Instant.ofEpochMilli(oneMillis);
530         LocalDateTime oneLocalDateTime = LocalDateTime.ofInstant(oneInstant, zoneId);
531 
532         Instant twoInstant = Instant.ofEpochMilli(twoMillis);
533         LocalDateTime twoLocalDateTime = LocalDateTime.ofInstant(twoInstant, zoneId);
534 
535         return (oneLocalDateTime.getYear() == twoLocalDateTime.getYear())
536                 && (oneLocalDateTime.getMonthValue() == twoLocalDateTime.getMonthValue())
537                 && (oneLocalDateTime.getDayOfMonth() == twoLocalDateTime.getDayOfMonth());
538     }
539 
540     /**
541      * Formats a date or a time range according to the local conventions.
542      * <p>
543      * Note that this is a convenience method. Using it involves creating an
544      * internal {@link java.util.Formatter} instance on-the-fly, which is
545      * somewhat costly in terms of memory and time. This is probably acceptable
546      * if you use the method only rarely, but if you rely on it for formatting a
547      * large number of dates, consider creating and reusing your own
548      * {@link java.util.Formatter} instance and use the version of
549      * {@link #formatDateRange(Context, long, long, int) formatDateRange}
550      * that takes a {@link java.util.Formatter}.
551      *
552      * @param context the context is required only if the time is shown
553      * @param startMillis the start time in UTC milliseconds
554      * @param endMillis the end time in UTC milliseconds
555      * @param flags a bit mask of options See
556      * {@link #formatDateRange(Context, Formatter, long, long, int, String) formatDateRange}
557      * @return a string containing the formatted date/time range.
558      */
formatDateRange(Context context, long startMillis, long endMillis, int flags)559     public static String formatDateRange(Context context, long startMillis,
560             long endMillis, int flags) {
561         Formatter f = new Formatter(new StringBuilder(50), Locale.getDefault());
562         return formatDateRange(context, f, startMillis, endMillis, flags).toString();
563     }
564 
565     /**
566      * Formats a date or a time range according to the local conventions.
567      * <p>
568      * Note that this is a convenience method for formatting the date or
569      * time range in the local time zone. If you want to specify the time
570      * zone please use
571      * {@link #formatDateRange(Context, Formatter, long, long, int, String) formatDateRange}.
572      *
573      * @param context the context is required only if the time is shown
574      * @param formatter the Formatter used for formatting the date range.
575      * Note: be sure to call setLength(0) on StringBuilder passed to
576      * the Formatter constructor unless you want the results to accumulate.
577      * @param startMillis the start time in UTC milliseconds
578      * @param endMillis the end time in UTC milliseconds
579      * @param flags a bit mask of options See
580      * {@link #formatDateRange(Context, Formatter, long, long, int, String) formatDateRange}
581      * @return a string containing the formatted date/time range.
582      */
formatDateRange(Context context, Formatter formatter, long startMillis, long endMillis, int flags)583     public static Formatter formatDateRange(Context context, Formatter formatter, long startMillis,
584             long endMillis, int flags) {
585         return formatDateRange(context, formatter, startMillis, endMillis, flags, null);
586     }
587 
588     /**
589      * Formats a date or a time range according to the local conventions.
590      *
591      * <p>
592      * Example output strings (date formats in these examples are shown using
593      * the US date format convention but that may change depending on the
594      * local settings):
595      * <ul>
596      *   <li>10:15am</li>
597      *   <li>3:00pm - 4:00pm</li>
598      *   <li>3pm - 4pm</li>
599      *   <li>3PM - 4PM</li>
600      *   <li>08:00 - 17:00</li>
601      *   <li>Oct 9</li>
602      *   <li>Tue, Oct 9</li>
603      *   <li>October 9, 2007</li>
604      *   <li>Oct 9 - 10</li>
605      *   <li>Oct 9 - 10, 2007</li>
606      *   <li>Oct 28 - Nov 3, 2007</li>
607      *   <li>Dec 31, 2007 - Jan 1, 2008</li>
608      *   <li>Oct 9, 8:00am - Oct 10, 5:00pm</li>
609      *   <li>12/31/2007 - 01/01/2008</li>
610      * </ul>
611      *
612      * <p>
613      * The flags argument is a bitmask of options from the following list:
614      *
615      * <ul>
616      *   <li>FORMAT_SHOW_TIME</li>
617      *   <li>FORMAT_SHOW_WEEKDAY</li>
618      *   <li>FORMAT_SHOW_YEAR</li>
619      *   <li>FORMAT_SHOW_DATE</li>
620      *   <li>FORMAT_NO_MONTH_DAY</li>
621      *   <li>FORMAT_12HOUR</li>
622      *   <li>FORMAT_24HOUR</li>
623      *   <li>FORMAT_CAP_AMPM</li>
624      *   <li>FORMAT_NO_NOON</li>
625      *   <li>FORMAT_CAP_NOON</li>
626      *   <li>FORMAT_NO_MIDNIGHT</li>
627      *   <li>FORMAT_CAP_MIDNIGHT</li>
628      *   <li>FORMAT_UTC</li>
629      *   <li>FORMAT_ABBREV_TIME</li>
630      *   <li>FORMAT_ABBREV_WEEKDAY</li>
631      *   <li>FORMAT_ABBREV_MONTH</li>
632      *   <li>FORMAT_ABBREV_ALL</li>
633      *   <li>FORMAT_NUMERIC_DATE</li>
634      * </ul>
635      *
636      * <p>
637      * If FORMAT_SHOW_TIME is set, the time is shown as part of the date range.
638      * If the start and end time are the same, then just the start time is
639      * shown.
640      *
641      * <p>
642      * If FORMAT_SHOW_WEEKDAY is set, then the weekday is shown.
643      *
644      * <p>
645      * If FORMAT_SHOW_YEAR is set, then the year is always shown.
646      * If FORMAT_SHOW_YEAR is not set, then the year
647      * is shown only if it is different from the current year, or if the start
648      * and end dates fall on different years.
649      *
650      * <p>
651      * Normally the date is shown unless the start and end day are the same.
652      * If FORMAT_SHOW_DATE is set, then the date is always shown, even for
653      * same day ranges.
654      *
655      * <p>
656      * If FORMAT_NO_MONTH_DAY is set, then if the date is shown, just the
657      * month name will be shown, not the day of the month.  For example,
658      * "January, 2008" instead of "January 6 - 12, 2008".
659      *
660      * <p>
661      * If FORMAT_CAP_AMPM is set and 12-hour time is used, then the "AM"
662      * and "PM" are capitalized.  You should not use this flag
663      * because in some locales these terms cannot be capitalized, and in
664      * many others it doesn't make sense to do so even though it is possible.
665      *
666      * <p>
667      * If FORMAT_NO_NOON is set and 12-hour time is used, then "12pm" is
668      * shown instead of "noon".
669      *
670      * <p>
671      * If FORMAT_CAP_NOON is set and 12-hour time is used, then "Noon" is
672      * shown instead of "noon".  You should probably not use this flag
673      * because in many locales it will not make sense to capitalize
674      * the term.
675      *
676      * <p>
677      * If FORMAT_NO_MIDNIGHT is set and 12-hour time is used, then "12am" is
678      * shown instead of "midnight".
679      *
680      * <p>
681      * If FORMAT_CAP_MIDNIGHT is set and 12-hour time is used, then "Midnight"
682      * is shown instead of "midnight".  You should probably not use this
683      * flag because in many locales it will not make sense to capitalize
684      * the term.
685      *
686      * <p>
687      * If FORMAT_12HOUR is set and the time is shown, then the time is
688      * shown in the 12-hour time format. You should not normally set this.
689      * Instead, let the time format be chosen automatically according to the
690      * system settings. If both FORMAT_12HOUR and FORMAT_24HOUR are set, then
691      * FORMAT_24HOUR takes precedence.
692      *
693      * <p>
694      * If FORMAT_24HOUR is set and the time is shown, then the time is
695      * shown in the 24-hour time format. You should not normally set this.
696      * Instead, let the time format be chosen automatically according to the
697      * system settings. If both FORMAT_12HOUR and FORMAT_24HOUR are set, then
698      * FORMAT_24HOUR takes precedence.
699      *
700      * <p>
701      * If FORMAT_UTC is set, then the UTC time zone is used for the start
702      * and end milliseconds unless a time zone is specified. If a time zone
703      * is specified it will be used regardless of the FORMAT_UTC flag.
704      *
705      * <p>
706      * If FORMAT_ABBREV_TIME is set and 12-hour time format is used, then the
707      * start and end times (if shown) are abbreviated by not showing the minutes
708      * if they are zero.  For example, instead of "3:00pm" the time would be
709      * abbreviated to "3pm".
710      *
711      * <p>
712      * If FORMAT_ABBREV_WEEKDAY is set, then the weekday (if shown) is
713      * abbreviated to a 3-letter string.
714      *
715      * <p>
716      * If FORMAT_ABBREV_MONTH is set, then the month (if shown) is abbreviated
717      * to a 3-letter string.
718      *
719      * <p>
720      * If FORMAT_ABBREV_ALL is set, then the weekday and the month (if shown)
721      * are abbreviated to 3-letter strings.
722      *
723      * <p>
724      * If FORMAT_NUMERIC_DATE is set, then the date is shown in numeric format
725      * instead of using the name of the month.  For example, "12/31/2008"
726      * instead of "December 31, 2008".
727      *
728      * <p>
729      * If the end date ends at 12:00am at the beginning of a day, it is
730      * formatted as the end of the previous day in two scenarios:
731      * <ul>
732      *   <li>For single day events. This results in "8pm - midnight" instead of
733      *       "Nov 10, 8pm - Nov 11, 12am".</li>
734      *   <li>When the time is not displayed. This results in "Nov 10 - 11" for
735      *       an event with a start date of Nov 10 and an end date of Nov 12 at
736      *       00:00.</li>
737      * </ul>
738      *
739      * @param context the context is required only if the time is shown
740      * @param formatter the Formatter used for formatting the date range.
741      * Note: be sure to call setLength(0) on StringBuilder passed to
742      * the Formatter constructor unless you want the results to accumulate.
743      * @param startMillis the start time in UTC milliseconds
744      * @param endMillis the end time in UTC milliseconds
745      * @param flags a bit mask of options
746      * @param timeZone the id of the time zone to compute the string in. Use null for local
747      * or if the FORMAT_UTC flag is being used.
748      *
749      * @return the formatter with the formatted date/time range appended to the string buffer.
750      */
formatDateRange(Context context, Formatter formatter, long startMillis, long endMillis, int flags, String timeZone)751     public static Formatter formatDateRange(Context context, Formatter formatter, long startMillis,
752                                             long endMillis, int flags, String timeZone) {
753         // If we're being asked to format a time without being explicitly told whether to use
754         // the 12- or 24-hour clock, icu4c will fall back to the locale's preferred 12/24 format,
755         // but we want to fall back to the user's preference.
756         if ((flags & (FORMAT_SHOW_TIME | FORMAT_12HOUR | FORMAT_24HOUR)) == FORMAT_SHOW_TIME) {
757             flags |= DateFormat.is24HourFormat(context) ? FORMAT_24HOUR : FORMAT_12HOUR;
758         }
759 
760         String range = DateIntervalFormat.formatDateRange(startMillis, endMillis, flags, timeZone);
761         try {
762             formatter.out().append(range);
763         } catch (IOException impossible) {
764             throw new AssertionError(impossible);
765         }
766         return formatter;
767     }
768 
769     /**
770      * Formats a date or a time according to the local conventions. There are
771      * lots of options that allow the caller to control, for example, if the
772      * time is shown, if the day of the week is shown, if the month name is
773      * abbreviated, if noon is shown instead of 12pm, and so on. For the
774      * complete list of options, see the documentation for
775      * {@link #formatDateRange}.
776      * <p>
777      * Example output strings (date formats in these examples are shown using
778      * the US date format convention but that may change depending on the
779      * local settings):
780      * <ul>
781      *   <li>10:15am</li>
782      *   <li>3:00pm</li>
783      *   <li>3pm</li>
784      *   <li>3PM</li>
785      *   <li>08:00</li>
786      *   <li>17:00</li>
787      *   <li>noon</li>
788      *   <li>Noon</li>
789      *   <li>midnight</li>
790      *   <li>Midnight</li>
791      *   <li>Oct 31</li>
792      *   <li>Oct 31, 2007</li>
793      *   <li>October 31, 2007</li>
794      *   <li>10am, Oct 31</li>
795      *   <li>17:00, Oct 31</li>
796      *   <li>Wed</li>
797      *   <li>Wednesday</li>
798      *   <li>10am, Wed, Oct 31</li>
799      *   <li>Wed, Oct 31</li>
800      *   <li>Wednesday, Oct 31</li>
801      *   <li>Wed, Oct 31, 2007</li>
802      *   <li>Wed, October 31</li>
803      *   <li>10/31/2007</li>
804      * </ul>
805      *
806      * @param context the context is required only if the time is shown
807      * @param millis a point in time in UTC milliseconds
808      * @param flags a bit mask of formatting options
809      * @return a string containing the formatted date/time.
810      */
formatDateTime(Context context, long millis, int flags)811     public static String formatDateTime(Context context, long millis, int flags) {
812         return formatDateRange(context, millis, millis, flags);
813     }
814 
815     /**
816      * @return a relative time string to display the time expressed by millis.  Times
817      * are counted starting at midnight, which means that assuming that the current
818      * time is March 31st, 0:30:
819      * <ul>
820      *   <li>"millis=0:10 today" will be displayed as "0:10"</li>
821      *   <li>"millis=11:30pm the day before" will be displayed as "Mar 30"</li>
822      * </ul>
823      * If the given millis is in a different year, then the full date is
824      * returned in numeric format (e.g., "10/12/2008").
825      *
826      * @param withPreposition If true, the string returned will include the correct
827      * preposition ("at 9:20am", "on 10/12/2008" or "on May 29").
828      */
getRelativeTimeSpanString(Context c, long millis, boolean withPreposition)829     public static CharSequence getRelativeTimeSpanString(Context c, long millis,
830             boolean withPreposition) {
831 
832         String result;
833         long now = System.currentTimeMillis();
834         long span = Math.abs(now - millis);
835 
836         synchronized (DateUtils.class) {
837             if (sNowTime == null) {
838                 sNowTime = new Time();
839             }
840 
841             if (sThenTime == null) {
842                 sThenTime = new Time();
843             }
844 
845             sNowTime.set(now);
846             sThenTime.set(millis);
847 
848             int prepositionId;
849             if (span < DAY_IN_MILLIS && sNowTime.weekDay == sThenTime.weekDay) {
850                 // Same day
851                 int flags = FORMAT_SHOW_TIME;
852                 result = formatDateRange(c, millis, millis, flags);
853                 prepositionId = R.string.preposition_for_time;
854             } else if (sNowTime.year != sThenTime.year) {
855                 // Different years
856                 int flags = FORMAT_SHOW_DATE | FORMAT_SHOW_YEAR | FORMAT_NUMERIC_DATE;
857                 result = formatDateRange(c, millis, millis, flags);
858 
859                 // This is a date (like "10/31/2008" so use the date preposition)
860                 prepositionId = R.string.preposition_for_date;
861             } else {
862                 // Default
863                 int flags = FORMAT_SHOW_DATE | FORMAT_ABBREV_MONTH;
864                 result = formatDateRange(c, millis, millis, flags);
865                 prepositionId = R.string.preposition_for_date;
866             }
867             if (withPreposition) {
868                 Resources res = c.getResources();
869                 result = res.getString(prepositionId, result);
870             }
871         }
872         return result;
873     }
874 
875     /**
876      * Convenience function to return relative time string without preposition.
877      * @param c context for resources
878      * @param millis time in milliseconds
879      * @return {@link CharSequence} containing relative time.
880      * @see #getRelativeTimeSpanString(Context, long, boolean)
881      */
getRelativeTimeSpanString(Context c, long millis)882     public static CharSequence getRelativeTimeSpanString(Context c, long millis) {
883         return getRelativeTimeSpanString(c, millis, false /* no preposition */);
884     }
885 
886     private static Time sNowTime;
887     private static Time sThenTime;
888 }
889