1/* 2 * Copyright (C) 2010 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 17package com.android.contacts.util; 18 19import android.content.Context; 20import android.text.format.DateFormat; 21 22import java.text.ParsePosition; 23import java.text.SimpleDateFormat; 24import java.util.Calendar; 25import java.util.Date; 26import java.util.Locale; 27import java.util.TimeZone; 28 29/** 30 * Utility methods for processing dates. 31 */ 32public class DateUtils { 33 public static final TimeZone UTC_TIMEZONE = TimeZone.getTimeZone("UTC"); 34 35 // All the SimpleDateFormats in this class use the UTC timezone 36 public static final SimpleDateFormat NO_YEAR_DATE_FORMAT = 37 new SimpleDateFormat("--MM-dd", Locale.US); 38 /** 39 * When parsing a date without a year, the system assumes 1970, which wasn't a leap-year. 40 * Let's add a one-off hack for that day of the year 41 */ 42 public static final String NO_YEAR_DATE_FEB29TH = "--02-29"; 43 public static final SimpleDateFormat FULL_DATE_FORMAT = 44 new SimpleDateFormat("yyyy-MM-dd", Locale.US); 45 public static final SimpleDateFormat DATE_AND_TIME_FORMAT = 46 new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'", Locale.US); 47 public static final SimpleDateFormat NO_YEAR_DATE_AND_TIME_FORMAT = 48 new SimpleDateFormat("--MM-dd'T'HH:mm:ss.SSS'Z'", Locale.US); 49 50 // Variations of ISO 8601 date format. Do not change the order - it does affect the 51 // result in ambiguous cases. 52 private static final SimpleDateFormat[] DATE_FORMATS = { 53 FULL_DATE_FORMAT, 54 DATE_AND_TIME_FORMAT, 55 new SimpleDateFormat("yyyy-MM-dd'T'HH:mm'Z'", Locale.US), 56 new SimpleDateFormat("yyyyMMdd", Locale.US), 57 new SimpleDateFormat("yyyyMMdd'T'HHmmssSSS'Z'", Locale.US), 58 new SimpleDateFormat("yyyyMMdd'T'HHmmss'Z'", Locale.US), 59 new SimpleDateFormat("yyyyMMdd'T'HHmm'Z'", Locale.US), 60 }; 61 62 private static final java.text.DateFormat FORMAT_WITHOUT_YEAR_MONTH_FIRST = 63 new SimpleDateFormat("MMMM dd"); 64 65 private static final java.text.DateFormat FORMAT_WITHOUT_YEAR_DAY_FIRST = 66 new SimpleDateFormat("dd MMMM"); 67 68 static { 69 for (SimpleDateFormat format : DATE_FORMATS) { 70 format.setLenient(true); 71 format.setTimeZone(UTC_TIMEZONE); 72 } 73 NO_YEAR_DATE_FORMAT.setTimeZone(UTC_TIMEZONE); 74 FORMAT_WITHOUT_YEAR_MONTH_FIRST.setTimeZone(UTC_TIMEZONE); 75 FORMAT_WITHOUT_YEAR_DAY_FIRST.setTimeZone(UTC_TIMEZONE); 76 } 77 78 /** 79 * Parses the supplied string to see if it looks like a date. If so, 80 * returns the date. Otherwise, returns null. 81 */ 82 public static Date parseDate(String string) { 83 ParsePosition parsePosition = new ParsePosition(0); 84 for (int i = 0; i < DATE_FORMATS.length; i++) { 85 SimpleDateFormat f = DATE_FORMATS[i]; 86 synchronized (f) { 87 parsePosition.setIndex(0); 88 Date date = f.parse(string, parsePosition); 89 if (parsePosition.getIndex() == string.length()) { 90 return date; 91 } 92 } 93 } 94 return null; 95 } 96 97 private static final Date getUtcDate(int year, int month, int dayOfMonth) { 98 final Calendar calendar = Calendar.getInstance(UTC_TIMEZONE, Locale.US); 99 calendar.set(Calendar.YEAR, year); 100 calendar.set(Calendar.MONTH, month); 101 calendar.set(Calendar.DAY_OF_MONTH, dayOfMonth); 102 return calendar.getTime(); 103 } 104 105 /** 106 * Parses the supplied string to see if it looks like a date. If so, 107 * returns the same date in a cleaned-up format for the user. Otherwise, returns 108 * the supplied string unchanged. 109 */ 110 public static String formatDate(Context context, String string) { 111 if (string == null) { 112 return null; 113 } 114 115 string = string.trim(); 116 if (string.length() == 0) { 117 return string; 118 } 119 120 ParsePosition parsePosition = new ParsePosition(0); 121 122 final boolean noYearParsed; 123 Date date; 124 125 // Unfortunately, we can't parse Feb 29th correctly, so let's handle this day seperately 126 if (NO_YEAR_DATE_FEB29TH.equals(string)) { 127 date = getUtcDate(0, Calendar.FEBRUARY, 29); 128 noYearParsed = true; 129 } else { 130 synchronized (NO_YEAR_DATE_FORMAT) { 131 date = NO_YEAR_DATE_FORMAT.parse(string, parsePosition); 132 } 133 noYearParsed = parsePosition.getIndex() == string.length(); 134 } 135 136 if (noYearParsed) { 137 java.text.DateFormat outFormat = isMonthBeforeDay(context) 138 ? FORMAT_WITHOUT_YEAR_MONTH_FIRST 139 : FORMAT_WITHOUT_YEAR_DAY_FIRST; 140 synchronized (outFormat) { 141 return outFormat.format(date); 142 } 143 } 144 145 for (int i = 0; i < DATE_FORMATS.length; i++) { 146 SimpleDateFormat f = DATE_FORMATS[i]; 147 synchronized (f) { 148 parsePosition.setIndex(0); 149 date = f.parse(string, parsePosition); 150 if (parsePosition.getIndex() == string.length()) { 151 java.text.DateFormat outFormat = DateFormat.getDateFormat(context); 152 outFormat.setTimeZone(UTC_TIMEZONE); 153 return outFormat.format(date); 154 } 155 } 156 } 157 return string; 158 } 159 160 public static boolean isMonthBeforeDay(Context context) { 161 char[] dateFormatOrder = DateFormat.getDateFormatOrder(context); 162 for (int i = 0; i < dateFormatOrder.length; i++) { 163 if (dateFormatOrder[i] == DateFormat.DATE) { 164 return false; 165 } 166 if (dateFormatOrder[i] == DateFormat.MONTH) { 167 return true; 168 } 169 } 170 return false; 171 } 172} 173