/* * Copyright (C) 2007 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.common; import android.text.format.Time; import java.util.Calendar; import java.util.regex.Matcher; import java.util.regex.Pattern; /** * Helper for parsing an HTTP date. */ final class LegacyHttpDateTime { /* * Regular expression for parsing HTTP-date. * * Wdy, DD Mon YYYY HH:MM:SS GMT * RFC 822, updated by RFC 1123 * * Weekday, DD-Mon-YY HH:MM:SS GMT * RFC 850, obsoleted by RFC 1036 * * Wdy Mon DD HH:MM:SS YYYY * ANSI C's asctime() format * * with following variations * * Wdy, DD-Mon-YYYY HH:MM:SS GMT * Wdy, (SP)D Mon YYYY HH:MM:SS GMT * Wdy,DD Mon YYYY HH:MM:SS GMT * Wdy, DD-Mon-YY HH:MM:SS GMT * Wdy, DD Mon YYYY HH:MM:SS -HHMM * Wdy, DD Mon YYYY HH:MM:SS * Wdy Mon (SP)D HH:MM:SS YYYY * Wdy Mon DD HH:MM:SS YYYY GMT * * HH can be H if the first digit is zero. * * Mon can be the full name of the month. */ private static final String HTTP_DATE_RFC_REGEXP = "([0-9]{1,2})[- ]([A-Za-z]{3,9})[- ]([0-9]{2,4})[ ]" + "([0-9]{1,2}:[0-9][0-9]:[0-9][0-9])"; private static final String HTTP_DATE_ANSIC_REGEXP = "[ ]([A-Za-z]{3,9})[ ]+([0-9]{1,2})[ ]" + "([0-9]{1,2}:[0-9][0-9]:[0-9][0-9])[ ]([0-9]{2,4})"; /** * The compiled version of the HTTP-date regular expressions. */ private static final Pattern HTTP_DATE_RFC_PATTERN = Pattern.compile(HTTP_DATE_RFC_REGEXP); private static final Pattern HTTP_DATE_ANSIC_PATTERN = Pattern.compile(HTTP_DATE_ANSIC_REGEXP); private static class TimeOfDay { TimeOfDay(int h, int m, int s) { this.hour = h; this.minute = m; this.second = s; } int hour; int minute; int second; } public static long parse(String timeString) throws IllegalArgumentException { int date = 1; int month = Calendar.JANUARY; int year = 1970; TimeOfDay timeOfDay; Matcher rfcMatcher = HTTP_DATE_RFC_PATTERN.matcher(timeString); if (rfcMatcher.find()) { date = getDate(rfcMatcher.group(1)); month = getMonth(rfcMatcher.group(2)); year = getYear(rfcMatcher.group(3)); timeOfDay = getTime(rfcMatcher.group(4)); } else { Matcher ansicMatcher = HTTP_DATE_ANSIC_PATTERN.matcher(timeString); if (ansicMatcher.find()) { month = getMonth(ansicMatcher.group(1)); date = getDate(ansicMatcher.group(2)); timeOfDay = getTime(ansicMatcher.group(3)); year = getYear(ansicMatcher.group(4)); } else { throw new IllegalArgumentException(); } } // FIXME: Y2038 BUG! if (year >= 2038) { year = 2038; month = Calendar.JANUARY; date = 1; } Time time = new Time(Time.TIMEZONE_UTC); time.set(timeOfDay.second, timeOfDay.minute, timeOfDay.hour, date, month, year); return time.toMillis(false /* use isDst */); } private static int getDate(String dateString) { if (dateString.length() == 2) { return (dateString.charAt(0) - '0') * 10 + (dateString.charAt(1) - '0'); } else { return (dateString.charAt(0) - '0'); } } /* * jan = 9 + 0 + 13 = 22 * feb = 5 + 4 + 1 = 10 * mar = 12 + 0 + 17 = 29 * apr = 0 + 15 + 17 = 32 * may = 12 + 0 + 24 = 36 * jun = 9 + 20 + 13 = 42 * jul = 9 + 20 + 11 = 40 * aug = 0 + 20 + 6 = 26 * sep = 18 + 4 + 15 = 37 * oct = 14 + 2 + 19 = 35 * nov = 13 + 14 + 21 = 48 * dec = 3 + 4 + 2 = 9 */ private static int getMonth(String monthString) { int hash = Character.toLowerCase(monthString.charAt(0)) + Character.toLowerCase(monthString.charAt(1)) + Character.toLowerCase(monthString.charAt(2)) - 3 * 'a'; switch (hash) { case 22: return Calendar.JANUARY; case 10: return Calendar.FEBRUARY; case 29: return Calendar.MARCH; case 32: return Calendar.APRIL; case 36: return Calendar.MAY; case 42: return Calendar.JUNE; case 40: return Calendar.JULY; case 26: return Calendar.AUGUST; case 37: return Calendar.SEPTEMBER; case 35: return Calendar.OCTOBER; case 48: return Calendar.NOVEMBER; case 9: return Calendar.DECEMBER; default: throw new IllegalArgumentException(); } } private static int getYear(String yearString) { if (yearString.length() == 2) { int year = (yearString.charAt(0) - '0') * 10 + (yearString.charAt(1) - '0'); if (year >= 70) { return year + 1900; } else { return year + 2000; } } else if (yearString.length() == 3) { // According to RFC 2822, three digit years should be added to 1900. int year = (yearString.charAt(0) - '0') * 100 + (yearString.charAt(1) - '0') * 10 + (yearString.charAt(2) - '0'); return year + 1900; } else if (yearString.length() == 4) { return (yearString.charAt(0) - '0') * 1000 + (yearString.charAt(1) - '0') * 100 + (yearString.charAt(2) - '0') * 10 + (yearString.charAt(3) - '0'); } else { return 1970; } } private static TimeOfDay getTime(String timeString) { // HH might be H int i = 0; int hour = timeString.charAt(i++) - '0'; if (timeString.charAt(i) != ':') hour = hour * 10 + (timeString.charAt(i++) - '0'); // Skip ':' i++; int minute = (timeString.charAt(i++) - '0') * 10 + (timeString.charAt(i++) - '0'); // Skip ':' i++; int second = (timeString.charAt(i++) - '0') * 10 + (timeString.charAt(i++) - '0'); return new TimeOfDay(hour, minute, second); } }