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+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.contacts.common.util;
+
+import android.content.Context;
+import android.text.format.DateFormat;
+import android.text.format.Time;
+import java.text.ParsePosition;
+import java.text.SimpleDateFormat;
+import java.util.Calendar;
+import java.util.Date;
+import java.util.GregorianCalendar;
+import java.util.Locale;
+import java.util.TimeZone;
+
+/** Utility methods for processing dates. */
+public class DateUtils {
+
+ public static final TimeZone UTC_TIMEZONE = TimeZone.getTimeZone("UTC");
+
+ /**
+ * When parsing a date without a year, the system assumes 1970, which wasn't a leap-year. Let's
+ * add a one-off hack for that day of the year
+ */
+ public static final String NO_YEAR_DATE_FEB29TH = "--02-29";
+
+ // Variations of ISO 8601 date format. Do not change the order - it does affect the
+ // result in ambiguous cases.
+ private static final SimpleDateFormat[] DATE_FORMATS = {
+ CommonDateUtils.FULL_DATE_FORMAT,
+ CommonDateUtils.DATE_AND_TIME_FORMAT,
+ new SimpleDateFormat("yyyy-MM-dd'T'HH:mm'Z'", Locale.US),
+ new SimpleDateFormat("yyyyMMdd", Locale.US),
+ new SimpleDateFormat("yyyyMMdd'T'HHmmssSSS'Z'", Locale.US),
+ new SimpleDateFormat("yyyyMMdd'T'HHmmss'Z'", Locale.US),
+ new SimpleDateFormat("yyyyMMdd'T'HHmm'Z'", Locale.US),
+ };
+
+ static {
+ for (SimpleDateFormat format : DATE_FORMATS) {
+ format.setLenient(true);
+ format.setTimeZone(UTC_TIMEZONE);
+ }
+ CommonDateUtils.NO_YEAR_DATE_FORMAT.setTimeZone(UTC_TIMEZONE);
+ }
+
+ /**
+ * Parses the supplied string to see if it looks like a date.
+ *
+ * @param string The string representation of the provided date
+ * @param mustContainYear If true, the string is parsed as a date containing a year. If false, the
+ * string is parsed into a valid date even if the year field is missing.
+ * @return A Calendar object corresponding to the date if the string is successfully parsed. If
+ * not, null is returned.
+ */
+ public static Calendar parseDate(String string, boolean mustContainYear) {
+ ParsePosition parsePosition = new ParsePosition(0);
+ Date date;
+ if (!mustContainYear) {
+ final boolean noYearParsed;
+ // Unfortunately, we can't parse Feb 29th correctly, so let's handle this day seperately
+ if (NO_YEAR_DATE_FEB29TH.equals(string)) {
+ return getUtcDate(0, Calendar.FEBRUARY, 29);
+ } else {
+ synchronized (CommonDateUtils.NO_YEAR_DATE_FORMAT) {
+ date = CommonDateUtils.NO_YEAR_DATE_FORMAT.parse(string, parsePosition);
+ }
+ noYearParsed = parsePosition.getIndex() == string.length();
+ }
+
+ if (noYearParsed) {
+ return getUtcDate(date, true);
+ }
+ }
+ for (int i = 0; i < DATE_FORMATS.length; i++) {
+ SimpleDateFormat f = DATE_FORMATS[i];
+ synchronized (f) {
+ parsePosition.setIndex(0);
+ date = f.parse(string, parsePosition);
+ if (parsePosition.getIndex() == string.length()) {
+ return getUtcDate(date, false);
+ }
+ }
+ }
+ return null;
+ }
+
+ private static final Calendar getUtcDate(Date date, boolean noYear) {
+ final Calendar calendar = Calendar.getInstance(UTC_TIMEZONE, Locale.US);
+ calendar.setTime(date);
+ if (noYear) {
+ calendar.set(Calendar.YEAR, 0);
+ }
+ return calendar;
+ }
+
+ private static final Calendar getUtcDate(int year, int month, int dayOfMonth) {
+ final Calendar calendar = Calendar.getInstance(UTC_TIMEZONE, Locale.US);
+ calendar.clear();
+ calendar.set(Calendar.YEAR, year);
+ calendar.set(Calendar.MONTH, month);
+ calendar.set(Calendar.DAY_OF_MONTH, dayOfMonth);
+ return calendar;
+ }
+
+ public static boolean isYearSet(Calendar cal) {
+ // use the Calendar.YEAR field to track whether or not the year is set instead of
+ // Calendar.isSet() because doing Calendar.get() causes Calendar.isSet() to become
+ // true irregardless of what the previous value was
+ return cal.get(Calendar.YEAR) > 1;
+ }
+
+ /**
+ * Same as {@link #formatDate(Context context, String string, boolean longForm)}, with longForm
+ * set to {@code true} by default.
+ *
+ * @param context Valid context
+ * @param string String representation of a date to parse
+ * @return Returns the same date in a cleaned up format. If the supplied string does not look like
+ * a date, return it unchanged.
+ */
+ public static String formatDate(Context context, String string) {
+ return formatDate(context, string, true);
+ }
+
+ /**
+ * Parses the supplied string to see if it looks like a date.
+ *
+ * @param context Valid context
+ * @param string String representation of a date to parse
+ * @param longForm If true, return the date formatted into its long string representation. If
+ * false, return the date formatted using its short form representation (i.e. 12/11/2012)
+ * @return Returns the same date in a cleaned up format. If the supplied string does not look like
+ * a date, return it unchanged.
+ */
+ public static String formatDate(Context context, String string, boolean longForm) {
+ if (string == null) {
+ return null;
+ }
+
+ string = string.trim();
+ if (string.length() == 0) {
+ return string;
+ }
+ final Calendar cal = parseDate(string, false);
+
+ // we weren't able to parse the string successfully so just return it unchanged
+ if (cal == null) {
+ return string;
+ }
+
+ final boolean isYearSet = isYearSet(cal);
+ final java.text.DateFormat outFormat;
+ if (!isYearSet) {
+ outFormat = getLocalizedDateFormatWithoutYear(context);
+ } else {
+ outFormat =
+ longForm ? DateFormat.getLongDateFormat(context) : DateFormat.getDateFormat(context);
+ }
+ synchronized (outFormat) {
+ outFormat.setTimeZone(UTC_TIMEZONE);
+ return outFormat.format(cal.getTime());
+ }
+ }
+
+ public static boolean isMonthBeforeDay(Context context) {
+ char[] dateFormatOrder = DateFormat.getDateFormatOrder(context);
+ for (int i = 0; i < dateFormatOrder.length; i++) {
+ if (dateFormatOrder[i] == 'd') {
+ return false;
+ }
+ if (dateFormatOrder[i] == 'M') {
+ return true;
+ }
+ }
+ return false;
+ }
+
+ /**
+ * Returns a SimpleDateFormat object without the year fields by using a regular expression to
+ * eliminate the year in the string pattern. In the rare occurence that the resulting pattern
+ * cannot be reconverted into a SimpleDateFormat, it uses the provided context to determine
+ * whether the month field should be displayed before the day field, and returns either "MMMM dd"
+ * or "dd MMMM" converted into a SimpleDateFormat.
+ */
+ public static java.text.DateFormat getLocalizedDateFormatWithoutYear(Context context) {
+ final String pattern =
+ ((SimpleDateFormat) SimpleDateFormat.getDateInstance(java.text.DateFormat.LONG))
+ .toPattern();
+ // Determine the correct regex pattern for year.
+ // Special case handling for Spanish locale by checking for "de"
+ final String yearPattern =
+ pattern.contains("de") ? "[^Mm]*[Yy]+[^Mm]*" : "[^DdMm]*[Yy]+[^DdMm]*";
+ try {
+ // Eliminate the substring in pattern that matches the format for that of year
+ return new SimpleDateFormat(pattern.replaceAll(yearPattern, ""));
+ } catch (IllegalArgumentException e) {
+ return new SimpleDateFormat(DateUtils.isMonthBeforeDay(context) ? "MMMM dd" : "dd MMMM");
+ }
+ }
+
+ /**
+ * Given a calendar (possibly containing only a day of the year), returns the earliest possible
+ * anniversary of the date that is equal to or after the current point in time if the date does
+ * not contain a year, or the date converted to the local time zone (if the date contains a year.
+ *
+ * @param target The date we wish to convert(in the UTC time zone).
+ * @return If date does not contain a year (year < 1900), returns the next earliest anniversary
+ * that is after the current point in time (in the local time zone). Otherwise, returns the
+ * adjusted Date in the local time zone.
+ */
+ public static Date getNextAnnualDate(Calendar target) {
+ final Calendar today = Calendar.getInstance();
+ today.setTime(new Date());
+
+ // Round the current time to the exact start of today so that when we compare
+ // today against the target date, both dates are set to exactly 0000H.
+ today.set(Calendar.HOUR_OF_DAY, 0);
+ today.set(Calendar.MINUTE, 0);
+ today.set(Calendar.SECOND, 0);
+ today.set(Calendar.MILLISECOND, 0);
+
+ final boolean isYearSet = isYearSet(target);
+ final int targetYear = target.get(Calendar.YEAR);
+ final int targetMonth = target.get(Calendar.MONTH);
+ final int targetDay = target.get(Calendar.DAY_OF_MONTH);
+ final boolean isFeb29 = (targetMonth == Calendar.FEBRUARY && targetDay == 29);
+ final GregorianCalendar anniversary = new GregorianCalendar();
+ // Convert from the UTC date to the local date. Set the year to today's year if the
+ // there is no provided year (targetYear < 1900)
+ anniversary.set(!isYearSet ? today.get(Calendar.YEAR) : targetYear, targetMonth, targetDay);
+ // If the anniversary's date is before the start of today and there is no year set,
+ // increment the year by 1 so that the returned date is always equal to or greater than
+ // today. If the day is a leap year, keep going until we get the next leap year anniversary
+ // Otherwise if there is already a year set, simply return the exact date.
+ if (!isYearSet) {
+ int anniversaryYear = today.get(Calendar.YEAR);
+ if (anniversary.before(today) || (isFeb29 && !anniversary.isLeapYear(anniversaryYear))) {
+ // If the target date is not Feb 29, then set the anniversary to the next year.
+ // Otherwise, keep going until we find the next leap year (this is not guaranteed
+ // to be in 4 years time).
+ do {
+ anniversaryYear += 1;
+ } while (isFeb29 && !anniversary.isLeapYear(anniversaryYear));
+ anniversary.set(anniversaryYear, targetMonth, targetDay);
+ }
+ }
+ return anniversary.getTime();
+ }
+
+ /**
+ * Determine the difference, in days between two dates. Uses similar logic as the {@link
+ * android.text.format.DateUtils.getRelativeTimeSpanString} method.
+ *
+ * @param time Instance of time object to use for calculations.
+ * @param date1 First date to check.
+ * @param date2 Second date to check.
+ * @return The absolute difference in days between the two dates.
+ */
+ public static int getDayDifference(Time time, long date1, long date2) {
+ time.set(date1);
+ int startDay = Time.getJulianDay(date1, time.gmtoff);
+
+ time.set(date2);
+ int currentDay = Time.getJulianDay(date2, time.gmtoff);
+
+ return Math.abs(currentDay - startDay);
+ }
+}