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/*
* Copyright (C) 2006 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 android.util;
import android.content.res.Resources;
import android.content.res.XmlResourceParser;
import android.os.SystemClock;
import android.text.format.DateUtils;
import com.android.internal.util.XmlUtils;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Collection;
import java.util.Date;
import java.util.TimeZone;
import libcore.util.ZoneInfoDB;
/**
* A class containing utility methods related to time zones.
*/
public class TimeUtils {
/** @hide */ public TimeUtils() {}
private static final boolean DBG = false;
private static final String TAG = "TimeUtils";
/** Cached results of getTineZones */
private static final Object sLastLockObj = new Object();
private static ArrayList sLastZones = null;
private static String sLastCountry = null;
/** Cached results of getTimeZonesWithUniqueOffsets */
private static final Object sLastUniqueLockObj = new Object();
private static ArrayList sLastUniqueZoneOffsets = null;
private static String sLastUniqueCountry = null;
/**
* Tries to return a time zone that would have had the specified offset
* and DST value at the specified moment in the specified country.
* Returns null if no suitable zone could be found.
*/
public static TimeZone getTimeZone(int offset, boolean dst, long when, String country) {
TimeZone best = null;
final Date d = new Date(when);
TimeZone current = TimeZone.getDefault();
String currentName = current.getID();
int currentOffset = current.getOffset(when);
boolean currentDst = current.inDaylightTime(d);
for (TimeZone tz : getTimeZones(country)) {
// If the current time zone is from the right country
// and meets the other known properties, keep it
// instead of changing to another one.
if (tz.getID().equals(currentName)) {
if (currentOffset == offset && currentDst == dst) {
return current;
}
}
// Otherwise, take the first zone from the right
// country that has the correct current offset and DST.
// (Keep iterating instead of returning in case we
// haven't encountered the current time zone yet.)
if (best == null) {
if (tz.getOffset(when) == offset &&
tz.inDaylightTime(d) == dst) {
best = tz;
}
}
}
return best;
}
/**
* Return list of unique time zones for the country. Do not modify
*
* @param country to find
* @return list of unique time zones, maybe empty but never null. Do not modify.
* @hide
*/
public static ArrayList getTimeZonesWithUniqueOffsets(String country) {
synchronized(sLastUniqueLockObj) {
if ((country != null) && country.equals(sLastUniqueCountry)) {
if (DBG) {
Log.d(TAG, "getTimeZonesWithUniqueOffsets(" +
country + "): return cached version");
}
return sLastUniqueZoneOffsets;
}
}
Collection zones = getTimeZones(country);
ArrayList uniqueTimeZones = new ArrayList();
for (TimeZone zone : zones) {
// See if we already have this offset,
// Using slow but space efficient and these are small.
boolean found = false;
for (int i = 0; i < uniqueTimeZones.size(); i++) {
if (uniqueTimeZones.get(i).getRawOffset() == zone.getRawOffset()) {
found = true;
break;
}
}
if (found == false) {
if (DBG) {
Log.d(TAG, "getTimeZonesWithUniqueOffsets: add unique offset=" +
zone.getRawOffset() + " zone.getID=" + zone.getID());
}
uniqueTimeZones.add(zone);
}
}
synchronized(sLastUniqueLockObj) {
// Cache the last result
sLastUniqueZoneOffsets = uniqueTimeZones;
sLastUniqueCountry = country;
return sLastUniqueZoneOffsets;
}
}
/**
* Returns the time zones for the country, which is the code
* attribute of the timezone element in time_zones_by_country.xml. Do not modify.
*
* @param country is a two character country code.
* @return TimeZone list, maybe empty but never null. Do not modify.
* @hide
*/
public static ArrayList getTimeZones(String country) {
synchronized (sLastLockObj) {
if ((country != null) && country.equals(sLastCountry)) {
if (DBG) Log.d(TAG, "getTimeZones(" + country + "): return cached version");
return sLastZones;
}
}
ArrayList tzs = new ArrayList();
if (country == null) {
if (DBG) Log.d(TAG, "getTimeZones(null): return empty list");
return tzs;
}
Resources r = Resources.getSystem();
XmlResourceParser parser = r.getXml(com.android.internal.R.xml.time_zones_by_country);
try {
XmlUtils.beginDocument(parser, "timezones");
while (true) {
XmlUtils.nextElement(parser);
String element = parser.getName();
if (element == null || !(element.equals("timezone"))) {
break;
}
String code = parser.getAttributeValue(null, "code");
if (country.equals(code)) {
if (parser.next() == XmlPullParser.TEXT) {
String zoneIdString = parser.getText();
TimeZone tz = TimeZone.getTimeZone(zoneIdString);
if (tz.getID().startsWith("GMT") == false) {
// tz.getID doesn't start not "GMT" so its valid
tzs.add(tz);
if (DBG) {
Log.d(TAG, "getTimeZone('" + country + "'): found tz.getID=="
+ ((tz != null) ? tz.getID() : ""));
}
}
}
}
}
} catch (XmlPullParserException e) {
Log.e(TAG, "Got xml parser exception getTimeZone('" + country + "'): e=", e);
} catch (IOException e) {
Log.e(TAG, "Got IO exception getTimeZone('" + country + "'): e=", e);
} finally {
parser.close();
}
synchronized(sLastLockObj) {
// Cache the last result;
sLastZones = tzs;
sLastCountry = country;
return sLastZones;
}
}
/**
* Returns a String indicating the version of the time zone database currently
* in use. The format of the string is dependent on the underlying time zone
* database implementation, but will typically contain the year in which the database
* was updated plus a letter from a to z indicating changes made within that year.
*
* Time zone database updates should be expected to occur periodically due to
* political and legal changes that cannot be anticipated in advance. Therefore,
* when computing the UTC time for a future event, applications should be aware that
* the results may differ following a time zone database update. This method allows
* applications to detect that a database change has occurred, and to recalculate any
* cached times accordingly.
*
*
The time zone database may be assumed to change only when the device runtime
* is restarted. Therefore, it is not necessary to re-query the database version
* during the lifetime of an activity.
*/
public static String getTimeZoneDatabaseVersion() {
return ZoneInfoDB.getInstance().getVersion();
}
/** @hide Field length that can hold 999 days of time */
public static final int HUNDRED_DAY_FIELD_LEN = 19;
private static final int SECONDS_PER_MINUTE = 60;
private static final int SECONDS_PER_HOUR = 60 * 60;
private static final int SECONDS_PER_DAY = 24 * 60 * 60;
/** @hide */
public static final long NANOS_PER_MS = 1000000;
private static final Object sFormatSync = new Object();
private static char[] sFormatStr = new char[HUNDRED_DAY_FIELD_LEN+5];
private static final long LARGEST_DURATION = (1000 * DateUtils.DAY_IN_MILLIS) - 1;
static private int accumField(int amt, int suffix, boolean always, int zeropad) {
if (amt > 99 || (always && zeropad >= 3)) {
return 3+suffix;
}
if (amt > 9 || (always && zeropad >= 2)) {
return 2+suffix;
}
if (always || amt > 0) {
return 1+suffix;
}
return 0;
}
static private int printField(char[] formatStr, int amt, char suffix, int pos,
boolean always, int zeropad) {
if (always || amt > 0) {
final int startPos = pos;
if ((always && zeropad >= 3) || amt > 99) {
int dig = amt/100;
formatStr[pos] = (char)(dig + '0');
pos++;
amt -= (dig*100);
}
if ((always && zeropad >= 2) || amt > 9 || startPos != pos) {
int dig = amt/10;
formatStr[pos] = (char)(dig + '0');
pos++;
amt -= (dig*10);
}
formatStr[pos] = (char)(amt + '0');
pos++;
formatStr[pos] = suffix;
pos++;
}
return pos;
}
private static int formatDurationLocked(long duration, int fieldLen) {
if (sFormatStr.length < fieldLen) {
sFormatStr = new char[fieldLen];
}
char[] formatStr = sFormatStr;
if (duration == 0) {
int pos = 0;
fieldLen -= 1;
while (pos < fieldLen) {
formatStr[pos++] = ' ';
}
formatStr[pos] = '0';
return pos+1;
}
char prefix;
if (duration > 0) {
prefix = '+';
} else {
prefix = '-';
duration = -duration;
}
if (duration > LARGEST_DURATION) {
duration = LARGEST_DURATION;
}
int millis = (int)(duration%1000);
int seconds = (int) Math.floor(duration / 1000);
int days = 0, hours = 0, minutes = 0;
if (seconds > SECONDS_PER_DAY) {
days = seconds / SECONDS_PER_DAY;
seconds -= days * SECONDS_PER_DAY;
}
if (seconds > SECONDS_PER_HOUR) {
hours = seconds / SECONDS_PER_HOUR;
seconds -= hours * SECONDS_PER_HOUR;
}
if (seconds > SECONDS_PER_MINUTE) {
minutes = seconds / SECONDS_PER_MINUTE;
seconds -= minutes * SECONDS_PER_MINUTE;
}
int pos = 0;
if (fieldLen != 0) {
int myLen = accumField(days, 1, false, 0);
myLen += accumField(hours, 1, myLen > 0, 2);
myLen += accumField(minutes, 1, myLen > 0, 2);
myLen += accumField(seconds, 1, myLen > 0, 2);
myLen += accumField(millis, 2, true, myLen > 0 ? 3 : 0) + 1;
while (myLen < fieldLen) {
formatStr[pos] = ' ';
pos++;
myLen++;
}
}
formatStr[pos] = prefix;
pos++;
int start = pos;
boolean zeropad = fieldLen != 0;
pos = printField(formatStr, days, 'd', pos, false, 0);
pos = printField(formatStr, hours, 'h', pos, pos != start, zeropad ? 2 : 0);
pos = printField(formatStr, minutes, 'm', pos, pos != start, zeropad ? 2 : 0);
pos = printField(formatStr, seconds, 's', pos, pos != start, zeropad ? 2 : 0);
pos = printField(formatStr, millis, 'm', pos, true, (zeropad && pos != start) ? 3 : 0);
formatStr[pos] = 's';
return pos + 1;
}
/** @hide Just for debugging; not internationalized. */
public static void formatDuration(long duration, StringBuilder builder) {
synchronized (sFormatSync) {
int len = formatDurationLocked(duration, 0);
builder.append(sFormatStr, 0, len);
}
}
/** @hide Just for debugging; not internationalized. */
public static void formatDuration(long duration, PrintWriter pw, int fieldLen) {
synchronized (sFormatSync) {
int len = formatDurationLocked(duration, fieldLen);
pw.print(new String(sFormatStr, 0, len));
}
}
/** @hide Just for debugging; not internationalized. */
public static void formatDuration(long duration, PrintWriter pw) {
formatDuration(duration, pw, 0);
}
/** @hide Just for debugging; not internationalized. */
public static void formatDuration(long time, long now, PrintWriter pw) {
if (time == 0) {
pw.print("--");
return;
}
formatDuration(time-now, pw, 0);
}
/** @hide Just for debugging; not internationalized. */
public static String formatUptime(long time) {
final long diff = time - SystemClock.uptimeMillis();
if (diff > 0) {
return time + " (in " + diff + " ms)";
}
if (diff < 0) {
return time + " (" + -diff + " ms ago)";
}
return time + " (now)";
}
/**
* Convert a System.currentTimeMillis() value to a time of day value like
* that printed in logs. MM-DD HH:MM:SS.MMM
*
* @param millis since the epoch (1/1/1970)
* @return String representation of the time.
* @hide
*/
public static String logTimeOfDay(long millis) {
Calendar c = Calendar.getInstance();
if (millis >= 0) {
c.setTimeInMillis(millis);
return String.format("%tm-%td %tH:%tM:%tS.%tL", c, c, c, c, c, c);
} else {
return Long.toString(millis);
}
}
}