/*
* 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 libcore.icu;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Locale;
import java.util.TimeZone;
import libcore.util.BasicLruCache;
import libcore.util.ZoneInfoDB;
/**
* Provides access to ICU's time zone name data.
*/
public final class TimeZoneNames {
private static final String[] availableTimeZoneIds = TimeZone.getAvailableIDs();
/*
* Offsets into the arrays returned by DateFormatSymbols.getZoneStrings.
*/
public static final int OLSON_NAME = 0;
public static final int LONG_NAME = 1;
public static final int SHORT_NAME = 2;
public static final int LONG_NAME_DST = 3;
public static final int SHORT_NAME_DST = 4;
public static final int NAME_COUNT = 5;
private static final ZoneStringsCache cachedZoneStrings = new ZoneStringsCache();
static {
// Ensure that we pull in the zone strings for the root locale, en_US, and the
// user's default locale. (All devices must support the root locale and en_US,
// and they're used for various system things like HTTP headers.) Pre-populating
// the cache is especially useful on Android because we'll share this via the Zygote.
cachedZoneStrings.get(Locale.ROOT);
cachedZoneStrings.get(Locale.US);
cachedZoneStrings.get(Locale.getDefault());
}
public static class ZoneStringsCache extends BasicLruCache<Locale, String[][]> {
public ZoneStringsCache() {
super(5); // Room for a handful of locales.
}
@Override protected String[][] create(Locale locale) {
long start = System.currentTimeMillis();
// Set up the 2D array used to hold the names. The first column contains the Olson ids.
String[][] result = new String[availableTimeZoneIds.length][5];
for (int i = 0; i < availableTimeZoneIds.length; ++i) {
result[i][0] = availableTimeZoneIds[i];
}
long nativeStart = System.currentTimeMillis();
fillZoneStrings(locale.toString(), result);
long nativeEnd = System.currentTimeMillis();
internStrings(result);
// Ending up in this method too often is an easy way to make your app slow, so we ensure
// it's easy to tell from the log (a) what we were doing, (b) how long it took, and
// (c) that it's all ICU's fault.
long end = System.currentTimeMillis();
long nativeDuration = nativeEnd - nativeStart;
long duration = end - start;
System.logI("Loaded time zone names for \"" + locale + "\" in " + duration + "ms" +
" (" + nativeDuration + "ms in ICU)");
return result;
}
// De-duplicate the strings (http://b/2672057).
private synchronized void internStrings(String[][] result) {
HashMap<String, String> internTable = new HashMap<String, String>();
for (int i = 0; i < result.length; ++i) {
for (int j = 1; j < NAME_COUNT; ++j) {
String original = result[i][j];
String nonDuplicate = internTable.get(original);
if (nonDuplicate == null) {
internTable.put(original, original);
} else {
result[i][j] = nonDuplicate;
}
}
}
}
}
private static final Comparator<String[]> ZONE_STRINGS_COMPARATOR = new Comparator<String[]>() {
public int compare(String[] lhs, String[] rhs) {
return lhs[OLSON_NAME].compareTo(rhs[OLSON_NAME]);
}
};
private TimeZoneNames() {}
/**
* Returns the appropriate string from 'zoneStrings'. Used with getZoneStrings.
*/
public static String getDisplayName(String[][] zoneStrings, String id, boolean daylight, int style) {
String[] needle = new String[] { id };
int index = Arrays.binarySearch(zoneStrings, needle, ZONE_STRINGS_COMPARATOR);
if (index >= 0) {
String[] row = zoneStrings[index];
if (daylight) {
return (style == TimeZone.LONG) ? row[LONG_NAME_DST] : row[SHORT_NAME_DST];
} else {
return (style == TimeZone.LONG) ? row[LONG_NAME] : row[SHORT_NAME];
}
}
return null;
}
/**
* Returns an array of time zone strings, as used by DateFormatSymbols.getZoneStrings.
*/
public static String[][] getZoneStrings(Locale locale) {
if (locale == null) {
locale = Locale.getDefault();
}
return cachedZoneStrings.get(locale);
}
/**
* Returns an array containing the time zone ids in use in the country corresponding to
* the given locale. This is not necessary for Java API, but is used by telephony as a
* fallback. We retrieve these strings from zone.tab rather than icu4c because the latter
* supplies them in alphabetical order where zone.tab has them in a kind of "importance"
* order (as defined in the zone.tab header).
*/
public static String[] forLocale(Locale locale) {
String countryCode = locale.getCountry();
ArrayList<String> ids = new ArrayList<String>();
for (String line : ZoneInfoDB.getInstance().getZoneTab().split("\n")) {
if (line.startsWith(countryCode)) {
int olsonIdStart = line.indexOf('\t', 4) + 1;
int olsonIdEnd = line.indexOf('\t', olsonIdStart);
if (olsonIdEnd == -1) {
olsonIdEnd = line.length(); // Not all zone.tab lines have a comment.
}
ids.add(line.substring(olsonIdStart, olsonIdEnd));
}
}
return ids.toArray(new String[ids.size()]);
}
public static native String getExemplarLocation(String locale, String tz);
private static native void fillZoneStrings(String locale, String[][] result);
}