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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 com.android.internal.R;
20 
21 import android.content.Context;
22 import android.content.res.Configuration;
23 import android.content.res.Resources;
24 
25 import java.io.IOException;
26 import java.util.Calendar;
27 import java.util.Date;
28 import java.util.Formatter;
29 import java.util.GregorianCalendar;
30 import java.util.Locale;
31 
32 import libcore.icu.DateIntervalFormat;
33 import libcore.icu.LocaleData;
34 
35 /**
36  * This class contains various date-related utilities for creating text for things like
37  * elapsed time and date ranges, strings for days of the week and months, and AM/PM text etc.
38  */
39 public class DateUtils
40 {
41     private static final Object sLock = new Object();
42     private static Configuration sLastConfig;
43     private static String sElapsedFormatMMSS;
44     private static String sElapsedFormatHMMSS;
45 
46     public static final long SECOND_IN_MILLIS = 1000;
47     public static final long MINUTE_IN_MILLIS = SECOND_IN_MILLIS * 60;
48     public static final long HOUR_IN_MILLIS = MINUTE_IN_MILLIS * 60;
49     public static final long DAY_IN_MILLIS = HOUR_IN_MILLIS * 24;
50     public static final long WEEK_IN_MILLIS = DAY_IN_MILLIS * 7;
51     /**
52      * This constant is actually the length of 364 days, not of a year!
53      */
54     public static final long YEAR_IN_MILLIS = WEEK_IN_MILLIS * 52;
55 
56     // The following FORMAT_* symbols are used for specifying the format of
57     // dates and times in the formatDateRange method.
58     public static final int FORMAT_SHOW_TIME = 0x00001;
59     public static final int FORMAT_SHOW_WEEKDAY = 0x00002;
60     public static final int FORMAT_SHOW_YEAR = 0x00004;
61     public static final int FORMAT_NO_YEAR = 0x00008;
62     public static final int FORMAT_SHOW_DATE = 0x00010;
63     public static final int FORMAT_NO_MONTH_DAY = 0x00020;
64     @Deprecated
65     public static final int FORMAT_12HOUR = 0x00040;
66     @Deprecated
67     public static final int FORMAT_24HOUR = 0x00080;
68     @Deprecated
69     public static final int FORMAT_CAP_AMPM = 0x00100;
70     public static final int FORMAT_NO_NOON = 0x00200;
71     @Deprecated
72     public static final int FORMAT_CAP_NOON = 0x00400;
73     public static final int FORMAT_NO_MIDNIGHT = 0x00800;
74     @Deprecated
75     public static final int FORMAT_CAP_MIDNIGHT = 0x01000;
76     /**
77      * @deprecated Use
78      * {@link #formatDateRange(Context, Formatter, long, long, int, String) formatDateRange}
79      * and pass in {@link Time#TIMEZONE_UTC Time.TIMEZONE_UTC} for the timeZone instead.
80      */
81     @Deprecated
82     public static final int FORMAT_UTC = 0x02000;
83     public static final int FORMAT_ABBREV_TIME = 0x04000;
84     public static final int FORMAT_ABBREV_WEEKDAY = 0x08000;
85     public static final int FORMAT_ABBREV_MONTH = 0x10000;
86     public static final int FORMAT_NUMERIC_DATE = 0x20000;
87     public static final int FORMAT_ABBREV_RELATIVE = 0x40000;
88     public static final int FORMAT_ABBREV_ALL = 0x80000;
89     @Deprecated
90     public static final int FORMAT_CAP_NOON_MIDNIGHT = (FORMAT_CAP_NOON | FORMAT_CAP_MIDNIGHT);
91     @Deprecated
92     public static final int FORMAT_NO_NOON_MIDNIGHT = (FORMAT_NO_NOON | FORMAT_NO_MIDNIGHT);
93 
94     // Date and time format strings that are constant and don't need to be
95     // translated.
96     /**
97      * This is not actually the preferred 24-hour date format in all locales.
98      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
99      */
100     @Deprecated
101     public static final String HOUR_MINUTE_24 = "%H:%M";
102     public static final String MONTH_FORMAT = "%B";
103     /**
104      * This is not actually a useful month name in all locales.
105      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
106      */
107     @Deprecated
108     public static final String ABBREV_MONTH_FORMAT = "%b";
109     public static final String NUMERIC_MONTH_FORMAT = "%m";
110     public static final String MONTH_DAY_FORMAT = "%-d";
111     public static final String YEAR_FORMAT = "%Y";
112     public static final String YEAR_FORMAT_TWO_DIGITS = "%g";
113     public static final String WEEKDAY_FORMAT = "%A";
114     public static final String ABBREV_WEEKDAY_FORMAT = "%a";
115 
116     /** @deprecated Do not use. */
117     public static final int[] sameYearTable = null;
118 
119     /** @deprecated Do not use. */
120     public static final int[] sameMonthTable = null;
121 
122     /**
123      * Request the full spelled-out name. For use with the 'abbrev' parameter of
124      * {@link #getDayOfWeekString} and {@link #getMonthString}.
125      *
126      * @more <p>
127      *       e.g. "Sunday" or "January"
128      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
129      */
130     @Deprecated
131     public static final int LENGTH_LONG = 10;
132 
133     /**
134      * Request an abbreviated version of the name. For use with the 'abbrev'
135      * parameter of {@link #getDayOfWeekString} and {@link #getMonthString}.
136      *
137      * @more <p>
138      *       e.g. "Sun" or "Jan"
139      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
140      */
141     @Deprecated
142     public static final int LENGTH_MEDIUM = 20;
143 
144     /**
145      * Request a shorter abbreviated version of the name.
146      * For use with the 'abbrev' parameter of {@link #getDayOfWeekString} and {@link #getMonthString}.
147      * @more
148      * <p>e.g. "Su" or "Jan"
149      * <p>In most languages, the results returned for LENGTH_SHORT will be the same as
150      * the results returned for {@link #LENGTH_MEDIUM}.
151      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
152      */
153     @Deprecated
154     public static final int LENGTH_SHORT = 30;
155 
156     /**
157      * Request an even shorter abbreviated version of the name.
158      * Do not use this.  Currently this will always return the same result
159      * as {@link #LENGTH_SHORT}.
160      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
161      */
162     @Deprecated
163     public static final int LENGTH_SHORTER = 40;
164 
165     /**
166      * Request an even shorter abbreviated version of the name.
167      * For use with the 'abbrev' parameter of {@link #getDayOfWeekString} and {@link #getMonthString}.
168      * @more
169      * <p>e.g. "S", "T", "T" or "J"
170      * <p>In some languages, the results returned for LENGTH_SHORTEST will be the same as
171      * the results returned for {@link #LENGTH_SHORT}.
172      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
173      */
174     @Deprecated
175     public static final int LENGTH_SHORTEST = 50;
176 
177     /**
178      * Return a string for the day of the week.
179      * @param dayOfWeek One of {@link Calendar#SUNDAY Calendar.SUNDAY},
180      *               {@link Calendar#MONDAY Calendar.MONDAY}, etc.
181      * @param abbrev One of {@link #LENGTH_LONG}, {@link #LENGTH_SHORT},
182      *               {@link #LENGTH_MEDIUM}, or {@link #LENGTH_SHORTEST}.
183      *               Note that in most languages, {@link #LENGTH_SHORT}
184      *               will return the same as {@link #LENGTH_MEDIUM}.
185      *               Undefined lengths will return {@link #LENGTH_MEDIUM}
186      *               but may return something different in the future.
187      * @throws IndexOutOfBoundsException if the dayOfWeek is out of bounds.
188      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
189      */
190     @Deprecated
getDayOfWeekString(int dayOfWeek, int abbrev)191     public static String getDayOfWeekString(int dayOfWeek, int abbrev) {
192         LocaleData d = LocaleData.get(Locale.getDefault());
193         String[] names;
194         switch (abbrev) {
195             case LENGTH_LONG:       names = d.longWeekdayNames;  break;
196             case LENGTH_MEDIUM:     names = d.shortWeekdayNames; break;
197             case LENGTH_SHORT:      names = d.shortWeekdayNames; break; // TODO
198             case LENGTH_SHORTER:    names = d.shortWeekdayNames; break; // TODO
199             case LENGTH_SHORTEST:   names = d.tinyWeekdayNames;  break;
200             default:                names = d.shortWeekdayNames; break;
201         }
202         return names[dayOfWeek];
203     }
204 
205     /**
206      * Return a localized string for AM or PM.
207      * @param ampm Either {@link Calendar#AM Calendar.AM} or {@link Calendar#PM Calendar.PM}.
208      * @throws IndexOutOfBoundsException if the ampm is out of bounds.
209      * @return Localized version of "AM" or "PM".
210      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
211      */
212     @Deprecated
getAMPMString(int ampm)213     public static String getAMPMString(int ampm) {
214         return LocaleData.get(Locale.getDefault()).amPm[ampm - Calendar.AM];
215     }
216 
217     /**
218      * Return a localized string for the month of the year.
219      * @param month One of {@link Calendar#JANUARY Calendar.JANUARY},
220      *               {@link Calendar#FEBRUARY Calendar.FEBRUARY}, etc.
221      * @param abbrev One of {@link #LENGTH_LONG}, {@link #LENGTH_MEDIUM},
222      *               or {@link #LENGTH_SHORTEST}.
223      *               Undefined lengths will return {@link #LENGTH_MEDIUM}
224      *               but may return something different in the future.
225      * @return Localized month of the year.
226      * @deprecated Use {@link java.text.SimpleDateFormat} instead.
227      */
228     @Deprecated
getMonthString(int month, int abbrev)229     public static String getMonthString(int month, int abbrev) {
230         LocaleData d = LocaleData.get(Locale.getDefault());
231         String[] names;
232         switch (abbrev) {
233             case LENGTH_LONG:       names = d.longMonthNames;  break;
234             case LENGTH_MEDIUM:     names = d.shortMonthNames; break;
235             case LENGTH_SHORT:      names = d.shortMonthNames; break;
236             case LENGTH_SHORTER:    names = d.shortMonthNames; break;
237             case LENGTH_SHORTEST:   names = d.tinyMonthNames;  break;
238             default:                names = d.shortMonthNames; break;
239         }
240         return names[month];
241     }
242 
243     /**
244      * Returns a string describing the elapsed time since startTime.
245      * @param startTime some time in the past.
246      * @return a String object containing the elapsed time.
247      * @see #getRelativeTimeSpanString(long, long, long)
248      */
getRelativeTimeSpanString(long startTime)249     public static CharSequence getRelativeTimeSpanString(long startTime) {
250         return getRelativeTimeSpanString(startTime, System.currentTimeMillis(), MINUTE_IN_MILLIS);
251     }
252 
253     /**
254      * Returns a string describing 'time' as a time relative to 'now'.
255      * <p>
256      * Time spans in the past are formatted like "42 minutes ago".
257      * Time spans in the future are formatted like "in 42 minutes".
258      *
259      * @param time the time to describe, in milliseconds
260      * @param now the current time in milliseconds
261      * @param minResolution the minimum timespan to report. For example, a time 3 seconds in the
262      *     past will be reported as "0 minutes ago" if this is set to MINUTE_IN_MILLIS. Pass one of
263      *     0, MINUTE_IN_MILLIS, HOUR_IN_MILLIS, DAY_IN_MILLIS, WEEK_IN_MILLIS
264      */
getRelativeTimeSpanString(long time, long now, long minResolution)265     public static CharSequence getRelativeTimeSpanString(long time, long now, long minResolution) {
266         int flags = FORMAT_SHOW_DATE | FORMAT_SHOW_YEAR | FORMAT_ABBREV_MONTH;
267         return getRelativeTimeSpanString(time, now, minResolution, flags);
268     }
269 
270     /**
271      * Returns a string describing 'time' as a time relative to 'now'.
272      * <p>
273      * Time spans in the past are formatted like "42 minutes ago". Time spans in
274      * the future are formatted like "in 42 minutes".
275      * <p>
276      * Can use {@link #FORMAT_ABBREV_RELATIVE} flag to use abbreviated relative
277      * times, like "42 mins ago".
278      *
279      * @param time the time to describe, in milliseconds
280      * @param now the current time in milliseconds
281      * @param minResolution the minimum timespan to report. For example, a time
282      *            3 seconds in the past will be reported as "0 minutes ago" if
283      *            this is set to MINUTE_IN_MILLIS. Pass one of 0,
284      *            MINUTE_IN_MILLIS, HOUR_IN_MILLIS, DAY_IN_MILLIS,
285      *            WEEK_IN_MILLIS
286      * @param flags a bit mask of formatting options, such as
287      *            {@link #FORMAT_NUMERIC_DATE} or
288      *            {@link #FORMAT_ABBREV_RELATIVE}
289      */
getRelativeTimeSpanString(long time, long now, long minResolution, int flags)290     public static CharSequence getRelativeTimeSpanString(long time, long now, long minResolution,
291             int flags) {
292         Resources r = Resources.getSystem();
293         boolean abbrevRelative = (flags & (FORMAT_ABBREV_RELATIVE | FORMAT_ABBREV_ALL)) != 0;
294 
295         boolean past = (now >= time);
296         long duration = Math.abs(now - time);
297 
298         int resId;
299         long count;
300         if (duration < MINUTE_IN_MILLIS && minResolution < MINUTE_IN_MILLIS) {
301             count = duration / SECOND_IN_MILLIS;
302             if (past) {
303                 if (abbrevRelative) {
304                     resId = com.android.internal.R.plurals.abbrev_num_seconds_ago;
305                 } else {
306                     resId = com.android.internal.R.plurals.num_seconds_ago;
307                 }
308             } else {
309                 if (abbrevRelative) {
310                     resId = com.android.internal.R.plurals.abbrev_in_num_seconds;
311                 } else {
312                     resId = com.android.internal.R.plurals.in_num_seconds;
313                 }
314             }
315         } else if (duration < HOUR_IN_MILLIS && minResolution < HOUR_IN_MILLIS) {
316             count = duration / MINUTE_IN_MILLIS;
317             if (past) {
318                 if (abbrevRelative) {
319                     resId = com.android.internal.R.plurals.abbrev_num_minutes_ago;
320                 } else {
321                     resId = com.android.internal.R.plurals.num_minutes_ago;
322                 }
323             } else {
324                 if (abbrevRelative) {
325                     resId = com.android.internal.R.plurals.abbrev_in_num_minutes;
326                 } else {
327                     resId = com.android.internal.R.plurals.in_num_minutes;
328                 }
329             }
330         } else if (duration < DAY_IN_MILLIS && minResolution < DAY_IN_MILLIS) {
331             count = duration / HOUR_IN_MILLIS;
332             if (past) {
333                 if (abbrevRelative) {
334                     resId = com.android.internal.R.plurals.abbrev_num_hours_ago;
335                 } else {
336                     resId = com.android.internal.R.plurals.num_hours_ago;
337                 }
338             } else {
339                 if (abbrevRelative) {
340                     resId = com.android.internal.R.plurals.abbrev_in_num_hours;
341                 } else {
342                     resId = com.android.internal.R.plurals.in_num_hours;
343                 }
344             }
345         } else if (duration < WEEK_IN_MILLIS && minResolution < WEEK_IN_MILLIS) {
346             return getRelativeDayString(r, time, now);
347         } else {
348             // We know that we won't be showing the time, so it is safe to pass
349             // in a null context.
350             return formatDateRange(null, time, time, flags);
351         }
352 
353         String format = r.getQuantityString(resId, (int) count);
354         return String.format(format, count);
355     }
356 
357     /**
358      * Return string describing the elapsed time since startTime formatted like
359      * "[relative time/date], [time]".
360      * <p>
361      * Example output strings for the US date format.
362      * <ul>
363      * <li>3 mins ago, 10:15 AM</li>
364      * <li>yesterday, 12:20 PM</li>
365      * <li>Dec 12, 4:12 AM</li>
366      * <li>11/14/2007, 8:20 AM</li>
367      * </ul>
368      *
369      * @param time some time in the past.
370      * @param minResolution the minimum elapsed time (in milliseconds) to report
371      *            when showing relative times. For example, a time 3 seconds in
372      *            the past will be reported as "0 minutes ago" if this is set to
373      *            {@link #MINUTE_IN_MILLIS}.
374      * @param transitionResolution the elapsed time (in milliseconds) at which
375      *            to stop reporting relative measurements. Elapsed times greater
376      *            than this resolution will default to normal date formatting.
377      *            For example, will transition from "6 days ago" to "Dec 12"
378      *            when using {@link #WEEK_IN_MILLIS}.
379      */
getRelativeDateTimeString(Context c, long time, long minResolution, long transitionResolution, int flags)380     public static CharSequence getRelativeDateTimeString(Context c, long time, long minResolution,
381             long transitionResolution, int flags) {
382         Resources r = Resources.getSystem();
383 
384         long now = System.currentTimeMillis();
385         long duration = Math.abs(now - time);
386 
387         // getRelativeTimeSpanString() doesn't correctly format relative dates
388         // above a week or exact dates below a day, so clamp
389         // transitionResolution as needed.
390         if (transitionResolution > WEEK_IN_MILLIS) {
391             transitionResolution = WEEK_IN_MILLIS;
392         } else if (transitionResolution < DAY_IN_MILLIS) {
393             transitionResolution = DAY_IN_MILLIS;
394         }
395 
396         CharSequence timeClause = formatDateRange(c, time, time, FORMAT_SHOW_TIME);
397 
398         String result;
399         if (duration < transitionResolution) {
400             CharSequence relativeClause = getRelativeTimeSpanString(time, now, minResolution, flags);
401             result = r.getString(com.android.internal.R.string.relative_time, relativeClause, timeClause);
402         } else {
403             CharSequence dateClause = getRelativeTimeSpanString(c, time, false);
404             result = r.getString(com.android.internal.R.string.date_time, dateClause, timeClause);
405         }
406 
407         return result;
408     }
409 
410     /**
411      * Returns a string describing a day relative to the current day. For example if the day is
412      * today this function returns "Today", if the day was a week ago it returns "7 days ago", and
413      * if the day is in 2 weeks it returns "in 14 days".
414      *
415      * @param r the resources
416      * @param day the relative day to describe in UTC milliseconds
417      * @param today the current time in UTC milliseconds
418      */
getRelativeDayString(Resources r, long day, long today)419     private static final String getRelativeDayString(Resources r, long day, long today) {
420         Locale locale = r.getConfiguration().locale;
421         if (locale == null) {
422             locale = Locale.getDefault();
423         }
424 
425         // TODO: use TimeZone.getOffset instead.
426         Time startTime = new Time();
427         startTime.set(day);
428         int startDay = Time.getJulianDay(day, startTime.gmtoff);
429 
430         Time currentTime = new Time();
431         currentTime.set(today);
432         int currentDay = Time.getJulianDay(today, currentTime.gmtoff);
433 
434         int days = Math.abs(currentDay - startDay);
435         boolean past = (today > day);
436 
437         // TODO: some locales name other days too, such as de_DE's "Vorgestern" (today - 2).
438         if (days == 1) {
439             if (past) {
440                 return LocaleData.get(locale).yesterday;
441             } else {
442                 return LocaleData.get(locale).tomorrow;
443             }
444         } else if (days == 0) {
445             return LocaleData.get(locale).today;
446         }
447 
448         int resId;
449         if (past) {
450             resId = com.android.internal.R.plurals.num_days_ago;
451         } else {
452             resId = com.android.internal.R.plurals.in_num_days;
453         }
454 
455         String format = r.getQuantityString(resId, days);
456         return String.format(format, days);
457     }
458 
initFormatStrings()459     private static void initFormatStrings() {
460         synchronized (sLock) {
461             initFormatStringsLocked();
462         }
463     }
464 
initFormatStringsLocked()465     private static void initFormatStringsLocked() {
466         Resources r = Resources.getSystem();
467         Configuration cfg = r.getConfiguration();
468         if (sLastConfig == null || !sLastConfig.equals(cfg)) {
469             sLastConfig = cfg;
470             sElapsedFormatMMSS = r.getString(com.android.internal.R.string.elapsed_time_short_format_mm_ss);
471             sElapsedFormatHMMSS = r.getString(com.android.internal.R.string.elapsed_time_short_format_h_mm_ss);
472         }
473     }
474 
475     /**
476      * Return given duration in a human-friendly format. For example, "4
477      * minutes" or "1 second". Returns only largest meaningful unit of time,
478      * from seconds up to hours.
479      *
480      * @hide
481      */
formatDuration(long millis)482     public static CharSequence formatDuration(long millis) {
483         final Resources res = Resources.getSystem();
484         if (millis >= HOUR_IN_MILLIS) {
485             final int hours = (int) ((millis + 1800000) / HOUR_IN_MILLIS);
486             return res.getQuantityString(
487                     com.android.internal.R.plurals.duration_hours, hours, hours);
488         } else if (millis >= MINUTE_IN_MILLIS) {
489             final int minutes = (int) ((millis + 30000) / MINUTE_IN_MILLIS);
490             return res.getQuantityString(
491                     com.android.internal.R.plurals.duration_minutes, minutes, minutes);
492         } else {
493             final int seconds = (int) ((millis + 500) / SECOND_IN_MILLIS);
494             return res.getQuantityString(
495                     com.android.internal.R.plurals.duration_seconds, seconds, seconds);
496         }
497     }
498 
499     /**
500      * Formats an elapsed time in the form "MM:SS" or "H:MM:SS"
501      * for display on the call-in-progress screen.
502      * @param elapsedSeconds the elapsed time in seconds.
503      */
formatElapsedTime(long elapsedSeconds)504     public static String formatElapsedTime(long elapsedSeconds) {
505         return formatElapsedTime(null, elapsedSeconds);
506     }
507 
508     /**
509      * Formats an elapsed time in a format like "MM:SS" or "H:MM:SS" (using a form
510      * suited to the current locale), similar to that used on the call-in-progress
511      * screen.
512      *
513      * @param recycle {@link StringBuilder} to recycle, or null to use a temporary one.
514      * @param elapsedSeconds the elapsed time in seconds.
515      */
formatElapsedTime(StringBuilder recycle, long elapsedSeconds)516     public static String formatElapsedTime(StringBuilder recycle, long elapsedSeconds) {
517         // Break the elapsed seconds into hours, minutes, and seconds.
518         long hours = 0;
519         long minutes = 0;
520         long seconds = 0;
521         if (elapsedSeconds >= 3600) {
522             hours = elapsedSeconds / 3600;
523             elapsedSeconds -= hours * 3600;
524         }
525         if (elapsedSeconds >= 60) {
526             minutes = elapsedSeconds / 60;
527             elapsedSeconds -= minutes * 60;
528         }
529         seconds = elapsedSeconds;
530 
531         // Create a StringBuilder if we weren't given one to recycle.
532         // TODO: if we cared, we could have a thread-local temporary StringBuilder.
533         StringBuilder sb = recycle;
534         if (sb == null) {
535             sb = new StringBuilder(8);
536         } else {
537             sb.setLength(0);
538         }
539 
540         // Format the broken-down time in a locale-appropriate way.
541         // TODO: use icu4c when http://unicode.org/cldr/trac/ticket/3407 is fixed.
542         Formatter f = new Formatter(sb, Locale.getDefault());
543         initFormatStrings();
544         if (hours > 0) {
545             return f.format(sElapsedFormatHMMSS, hours, minutes, seconds).toString();
546         } else {
547             return f.format(sElapsedFormatMMSS, minutes, seconds).toString();
548         }
549     }
550 
551     /**
552      * Format a date / time such that if the then is on the same day as now, it shows
553      * just the time and if it's a different day, it shows just the date.
554      *
555      * <p>The parameters dateFormat and timeFormat should each be one of
556      * {@link java.text.DateFormat#DEFAULT},
557      * {@link java.text.DateFormat#FULL},
558      * {@link java.text.DateFormat#LONG},
559      * {@link java.text.DateFormat#MEDIUM}
560      * or
561      * {@link java.text.DateFormat#SHORT}
562      *
563      * @param then the date to format
564      * @param now the base time
565      * @param dateStyle how to format the date portion.
566      * @param timeStyle how to format the time portion.
567      */
formatSameDayTime(long then, long now, int dateStyle, int timeStyle)568     public static final CharSequence formatSameDayTime(long then, long now,
569             int dateStyle, int timeStyle) {
570         Calendar thenCal = new GregorianCalendar();
571         thenCal.setTimeInMillis(then);
572         Date thenDate = thenCal.getTime();
573         Calendar nowCal = new GregorianCalendar();
574         nowCal.setTimeInMillis(now);
575 
576         java.text.DateFormat f;
577 
578         if (thenCal.get(Calendar.YEAR) == nowCal.get(Calendar.YEAR)
579                 && thenCal.get(Calendar.MONTH) == nowCal.get(Calendar.MONTH)
580                 && thenCal.get(Calendar.DAY_OF_MONTH) == nowCal.get(Calendar.DAY_OF_MONTH)) {
581             f = java.text.DateFormat.getTimeInstance(timeStyle);
582         } else {
583             f = java.text.DateFormat.getDateInstance(dateStyle);
584         }
585         return f.format(thenDate);
586     }
587 
588     /**
589      * @return true if the supplied when is today else false
590      */
isToday(long when)591     public static boolean isToday(long when) {
592         Time time = new Time();
593         time.set(when);
594 
595         int thenYear = time.year;
596         int thenMonth = time.month;
597         int thenMonthDay = time.monthDay;
598 
599         time.set(System.currentTimeMillis());
600         return (thenYear == time.year)
601                 && (thenMonth == time.month)
602                 && (thenMonthDay == time.monthDay);
603     }
604 
605     /**
606      * Formats a date or a time range according to the local conventions.
607      * <p>
608      * Note that this is a convenience method. Using it involves creating an
609      * internal {@link java.util.Formatter} instance on-the-fly, which is
610      * somewhat costly in terms of memory and time. This is probably acceptable
611      * if you use the method only rarely, but if you rely on it for formatting a
612      * large number of dates, consider creating and reusing your own
613      * {@link java.util.Formatter} instance and use the version of
614      * {@link #formatDateRange(Context, long, long, int) formatDateRange}
615      * that takes a {@link java.util.Formatter}.
616      *
617      * @param context the context is required only if the time is shown
618      * @param startMillis the start time in UTC milliseconds
619      * @param endMillis the end time in UTC milliseconds
620      * @param flags a bit mask of options See
621      * {@link #formatDateRange(Context, Formatter, long, long, int, String) formatDateRange}
622      * @return a string containing the formatted date/time range.
623      */
formatDateRange(Context context, long startMillis, long endMillis, int flags)624     public static String formatDateRange(Context context, long startMillis,
625             long endMillis, int flags) {
626         Formatter f = new Formatter(new StringBuilder(50), Locale.getDefault());
627         return formatDateRange(context, f, startMillis, endMillis, flags).toString();
628     }
629 
630     /**
631      * Formats a date or a time range according to the local conventions.
632      * <p>
633      * Note that this is a convenience method for formatting the date or
634      * time range in the local time zone. If you want to specify the time
635      * zone please use
636      * {@link #formatDateRange(Context, Formatter, long, long, int, String) formatDateRange}.
637      *
638      * @param context the context is required only if the time is shown
639      * @param formatter the Formatter used for formatting the date range.
640      * Note: be sure to call setLength(0) on StringBuilder passed to
641      * the Formatter constructor unless you want the results to accumulate.
642      * @param startMillis the start time in UTC milliseconds
643      * @param endMillis the end time in UTC milliseconds
644      * @param flags a bit mask of options See
645      * {@link #formatDateRange(Context, Formatter, long, long, int, String) formatDateRange}
646      * @return a string containing the formatted date/time range.
647      */
formatDateRange(Context context, Formatter formatter, long startMillis, long endMillis, int flags)648     public static Formatter formatDateRange(Context context, Formatter formatter, long startMillis,
649             long endMillis, int flags) {
650         return formatDateRange(context, formatter, startMillis, endMillis, flags, null);
651     }
652 
653     /**
654      * Formats a date or a time range according to the local conventions.
655      *
656      * <p>
657      * Example output strings (date formats in these examples are shown using
658      * the US date format convention but that may change depending on the
659      * local settings):
660      * <ul>
661      *   <li>10:15am</li>
662      *   <li>3:00pm - 4:00pm</li>
663      *   <li>3pm - 4pm</li>
664      *   <li>3PM - 4PM</li>
665      *   <li>08:00 - 17:00</li>
666      *   <li>Oct 9</li>
667      *   <li>Tue, Oct 9</li>
668      *   <li>October 9, 2007</li>
669      *   <li>Oct 9 - 10</li>
670      *   <li>Oct 9 - 10, 2007</li>
671      *   <li>Oct 28 - Nov 3, 2007</li>
672      *   <li>Dec 31, 2007 - Jan 1, 2008</li>
673      *   <li>Oct 9, 8:00am - Oct 10, 5:00pm</li>
674      *   <li>12/31/2007 - 01/01/2008</li>
675      * </ul>
676      *
677      * <p>
678      * The flags argument is a bitmask of options from the following list:
679      *
680      * <ul>
681      *   <li>FORMAT_SHOW_TIME</li>
682      *   <li>FORMAT_SHOW_WEEKDAY</li>
683      *   <li>FORMAT_SHOW_YEAR</li>
684      *   <li>FORMAT_SHOW_DATE</li>
685      *   <li>FORMAT_NO_MONTH_DAY</li>
686      *   <li>FORMAT_12HOUR</li>
687      *   <li>FORMAT_24HOUR</li>
688      *   <li>FORMAT_CAP_AMPM</li>
689      *   <li>FORMAT_NO_NOON</li>
690      *   <li>FORMAT_CAP_NOON</li>
691      *   <li>FORMAT_NO_MIDNIGHT</li>
692      *   <li>FORMAT_CAP_MIDNIGHT</li>
693      *   <li>FORMAT_UTC</li>
694      *   <li>FORMAT_ABBREV_TIME</li>
695      *   <li>FORMAT_ABBREV_WEEKDAY</li>
696      *   <li>FORMAT_ABBREV_MONTH</li>
697      *   <li>FORMAT_ABBREV_ALL</li>
698      *   <li>FORMAT_NUMERIC_DATE</li>
699      * </ul>
700      *
701      * <p>
702      * If FORMAT_SHOW_TIME is set, the time is shown as part of the date range.
703      * If the start and end time are the same, then just the start time is
704      * shown.
705      *
706      * <p>
707      * If FORMAT_SHOW_WEEKDAY is set, then the weekday is shown.
708      *
709      * <p>
710      * If FORMAT_SHOW_YEAR is set, then the year is always shown.
711      * If FORMAT_SHOW_YEAR is not set, then the year
712      * is shown only if it is different from the current year, or if the start
713      * and end dates fall on different years.
714      *
715      * <p>
716      * Normally the date is shown unless the start and end day are the same.
717      * If FORMAT_SHOW_DATE is set, then the date is always shown, even for
718      * same day ranges.
719      *
720      * <p>
721      * If FORMAT_NO_MONTH_DAY is set, then if the date is shown, just the
722      * month name will be shown, not the day of the month.  For example,
723      * "January, 2008" instead of "January 6 - 12, 2008".
724      *
725      * <p>
726      * If FORMAT_CAP_AMPM is set and 12-hour time is used, then the "AM"
727      * and "PM" are capitalized.  You should not use this flag
728      * because in some locales these terms cannot be capitalized, and in
729      * many others it doesn't make sense to do so even though it is possible.
730      *
731      * <p>
732      * If FORMAT_NO_NOON is set and 12-hour time is used, then "12pm" is
733      * shown instead of "noon".
734      *
735      * <p>
736      * If FORMAT_CAP_NOON is set and 12-hour time is used, then "Noon" is
737      * shown instead of "noon".  You should probably not use this flag
738      * because in many locales it will not make sense to capitalize
739      * the term.
740      *
741      * <p>
742      * If FORMAT_NO_MIDNIGHT is set and 12-hour time is used, then "12am" is
743      * shown instead of "midnight".
744      *
745      * <p>
746      * If FORMAT_CAP_MIDNIGHT is set and 12-hour time is used, then "Midnight"
747      * is shown instead of "midnight".  You should probably not use this
748      * flag because in many locales it will not make sense to capitalize
749      * the term.
750      *
751      * <p>
752      * If FORMAT_12HOUR is set and the time is shown, then the time is
753      * shown in the 12-hour time format. You should not normally set this.
754      * Instead, let the time format be chosen automatically according to the
755      * system settings. If both FORMAT_12HOUR and FORMAT_24HOUR are set, then
756      * FORMAT_24HOUR takes precedence.
757      *
758      * <p>
759      * If FORMAT_24HOUR is set and the time is shown, then the time is
760      * shown in the 24-hour time format. You should not normally set this.
761      * Instead, let the time format be chosen automatically according to the
762      * system settings. If both FORMAT_12HOUR and FORMAT_24HOUR are set, then
763      * FORMAT_24HOUR takes precedence.
764      *
765      * <p>
766      * If FORMAT_UTC is set, then the UTC time zone is used for the start
767      * and end milliseconds unless a time zone is specified. If a time zone
768      * is specified it will be used regardless of the FORMAT_UTC flag.
769      *
770      * <p>
771      * If FORMAT_ABBREV_TIME is set and 12-hour time format is used, then the
772      * start and end times (if shown) are abbreviated by not showing the minutes
773      * if they are zero.  For example, instead of "3:00pm" the time would be
774      * abbreviated to "3pm".
775      *
776      * <p>
777      * If FORMAT_ABBREV_WEEKDAY is set, then the weekday (if shown) is
778      * abbreviated to a 3-letter string.
779      *
780      * <p>
781      * If FORMAT_ABBREV_MONTH is set, then the month (if shown) is abbreviated
782      * to a 3-letter string.
783      *
784      * <p>
785      * If FORMAT_ABBREV_ALL is set, then the weekday and the month (if shown)
786      * are abbreviated to 3-letter strings.
787      *
788      * <p>
789      * If FORMAT_NUMERIC_DATE is set, then the date is shown in numeric format
790      * instead of using the name of the month.  For example, "12/31/2008"
791      * instead of "December 31, 2008".
792      *
793      * <p>
794      * If the end date ends at 12:00am at the beginning of a day, it is
795      * formatted as the end of the previous day in two scenarios:
796      * <ul>
797      *   <li>For single day events. This results in "8pm - midnight" instead of
798      *       "Nov 10, 8pm - Nov 11, 12am".</li>
799      *   <li>When the time is not displayed. This results in "Nov 10 - 11" for
800      *       an event with a start date of Nov 10 and an end date of Nov 12 at
801      *       00:00.</li>
802      * </ul>
803      *
804      * @param context the context is required only if the time is shown
805      * @param formatter the Formatter used for formatting the date range.
806      * Note: be sure to call setLength(0) on StringBuilder passed to
807      * the Formatter constructor unless you want the results to accumulate.
808      * @param startMillis the start time in UTC milliseconds
809      * @param endMillis the end time in UTC milliseconds
810      * @param flags a bit mask of options
811      * @param timeZone the time zone to compute the string in. Use null for local
812      * or if the FORMAT_UTC flag is being used.
813      *
814      * @return the formatter with the formatted date/time range appended to the string buffer.
815      */
formatDateRange(Context context, Formatter formatter, long startMillis, long endMillis, int flags, String timeZone)816     public static Formatter formatDateRange(Context context, Formatter formatter, long startMillis,
817                                             long endMillis, int flags, String timeZone) {
818         // If we're being asked to format a time without being explicitly told whether to use
819         // the 12- or 24-hour clock, icu4c will fall back to the locale's preferred 12/24 format,
820         // but we want to fall back to the user's preference.
821         if ((flags & (FORMAT_SHOW_TIME | FORMAT_12HOUR | FORMAT_24HOUR)) == FORMAT_SHOW_TIME) {
822             flags |= DateFormat.is24HourFormat(context) ? FORMAT_24HOUR : FORMAT_12HOUR;
823         }
824 
825         String range = DateIntervalFormat.formatDateRange(startMillis, endMillis, flags, timeZone);
826         try {
827             formatter.out().append(range);
828         } catch (IOException impossible) {
829             throw new AssertionError(impossible);
830         }
831         return formatter;
832     }
833 
834     /**
835      * Formats a date or a time according to the local conventions. There are
836      * lots of options that allow the caller to control, for example, if the
837      * time is shown, if the day of the week is shown, if the month name is
838      * abbreviated, if noon is shown instead of 12pm, and so on. For the
839      * complete list of options, see the documentation for
840      * {@link #formatDateRange}.
841      * <p>
842      * Example output strings (date formats in these examples are shown using
843      * the US date format convention but that may change depending on the
844      * local settings):
845      * <ul>
846      *   <li>10:15am</li>
847      *   <li>3:00pm</li>
848      *   <li>3pm</li>
849      *   <li>3PM</li>
850      *   <li>08:00</li>
851      *   <li>17:00</li>
852      *   <li>noon</li>
853      *   <li>Noon</li>
854      *   <li>midnight</li>
855      *   <li>Midnight</li>
856      *   <li>Oct 31</li>
857      *   <li>Oct 31, 2007</li>
858      *   <li>October 31, 2007</li>
859      *   <li>10am, Oct 31</li>
860      *   <li>17:00, Oct 31</li>
861      *   <li>Wed</li>
862      *   <li>Wednesday</li>
863      *   <li>10am, Wed, Oct 31</li>
864      *   <li>Wed, Oct 31</li>
865      *   <li>Wednesday, Oct 31</li>
866      *   <li>Wed, Oct 31, 2007</li>
867      *   <li>Wed, October 31</li>
868      *   <li>10/31/2007</li>
869      * </ul>
870      *
871      * @param context the context is required only if the time is shown
872      * @param millis a point in time in UTC milliseconds
873      * @param flags a bit mask of formatting options
874      * @return a string containing the formatted date/time.
875      */
formatDateTime(Context context, long millis, int flags)876     public static String formatDateTime(Context context, long millis, int flags) {
877         return formatDateRange(context, millis, millis, flags);
878     }
879 
880     /**
881      * @return a relative time string to display the time expressed by millis.  Times
882      * are counted starting at midnight, which means that assuming that the current
883      * time is March 31st, 0:30:
884      * <ul>
885      *   <li>"millis=0:10 today" will be displayed as "0:10"</li>
886      *   <li>"millis=11:30pm the day before" will be displayed as "Mar 30"</li>
887      * </ul>
888      * If the given millis is in a different year, then the full date is
889      * returned in numeric format (e.g., "10/12/2008").
890      *
891      * @param withPreposition If true, the string returned will include the correct
892      * preposition ("at 9:20am", "on 10/12/2008" or "on May 29").
893      */
getRelativeTimeSpanString(Context c, long millis, boolean withPreposition)894     public static CharSequence getRelativeTimeSpanString(Context c, long millis,
895             boolean withPreposition) {
896 
897         String result;
898         long now = System.currentTimeMillis();
899         long span = Math.abs(now - millis);
900 
901         synchronized (DateUtils.class) {
902             if (sNowTime == null) {
903                 sNowTime = new Time();
904             }
905 
906             if (sThenTime == null) {
907                 sThenTime = new Time();
908             }
909 
910             sNowTime.set(now);
911             sThenTime.set(millis);
912 
913             int prepositionId;
914             if (span < DAY_IN_MILLIS && sNowTime.weekDay == sThenTime.weekDay) {
915                 // Same day
916                 int flags = FORMAT_SHOW_TIME;
917                 result = formatDateRange(c, millis, millis, flags);
918                 prepositionId = R.string.preposition_for_time;
919             } else if (sNowTime.year != sThenTime.year) {
920                 // Different years
921                 int flags = FORMAT_SHOW_DATE | FORMAT_SHOW_YEAR | FORMAT_NUMERIC_DATE;
922                 result = formatDateRange(c, millis, millis, flags);
923 
924                 // This is a date (like "10/31/2008" so use the date preposition)
925                 prepositionId = R.string.preposition_for_date;
926             } else {
927                 // Default
928                 int flags = FORMAT_SHOW_DATE | FORMAT_ABBREV_MONTH;
929                 result = formatDateRange(c, millis, millis, flags);
930                 prepositionId = R.string.preposition_for_date;
931             }
932             if (withPreposition) {
933                 Resources res = c.getResources();
934                 result = res.getString(prepositionId, result);
935             }
936         }
937         return result;
938     }
939 
940     /**
941      * Convenience function to return relative time string without preposition.
942      * @param c context for resources
943      * @param millis time in milliseconds
944      * @return {@link CharSequence} containing relative time.
945      * @see #getRelativeTimeSpanString(Context, long, boolean)
946      */
getRelativeTimeSpanString(Context c, long millis)947     public static CharSequence getRelativeTimeSpanString(Context c, long millis) {
948         return getRelativeTimeSpanString(c, millis, false /* no preposition */);
949     }
950 
951     private static Time sNowTime;
952     private static Time sThenTime;
953 }
954