8181157: CLDR Timezone name fallback implementation
Reviewed-by: sherman, scolebourne
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package sun.util.cldr;
import static sun.util.locale.provider.LocaleProviderAdapter.Type;
import java.text.MessageFormat;
import java.util.Arrays;
import java.util.Locale;
import java.util.Objects;
import java.util.ResourceBundle;
import java.util.Set;
import java.util.TimeZone;
import java.util.stream.Collectors;
import sun.util.calendar.ZoneInfoFile;
import sun.util.locale.provider.LocaleProviderAdapter;
import sun.util.locale.provider.LocaleResources;
import sun.util.locale.provider.TimeZoneNameProviderImpl;
import sun.util.locale.provider.TimeZoneNameUtility;
/**
* Concrete implementation of the
* {@link java.util.spi.TimeZoneNameProvider TimeZoneNameProvider} class
* for the CLDR LocaleProviderAdapter.
*
* @author Naoto Sato
*/
public class CLDRTimeZoneNameProviderImpl extends TimeZoneNameProviderImpl {
private static final String NO_INHERITANCE_MARKER = "\u2205\u2205\u2205";
private static class AVAILABLE_IDS {
static final String[] INSTANCE =
Arrays.stream(ZoneInfoFile.getZoneIds())
.sorted()
.toArray(String[]::new);
}
// display name array indexes
private static final int INDEX_TZID = 0;
private static final int INDEX_STD_LONG = 1;
private static final int INDEX_STD_SHORT = 2;
private static final int INDEX_DST_LONG = 3;
private static final int INDEX_DST_SHORT = 4;
private static final int INDEX_GEN_LONG = 5;
private static final int INDEX_GEN_SHORT = 6;
public CLDRTimeZoneNameProviderImpl(Type type, Set<String> langtags) {
super(type, langtags);
}
@Override
protected String[] getDisplayNameArray(String id, Locale locale) {
String tzid = TimeZoneNameUtility.canonicalTZID(id).orElse(id);
String[] namesSuper = super.getDisplayNameArray(tzid, locale);
if (Objects.nonNull(namesSuper)) {
// CLDR's resource bundle has an translated entry for this id.
// Fix up names if needed, either missing or no-inheritance
namesSuper[INDEX_TZID] = id;
// Check if standard long name exists. If not, try to retrieve the name
// from language only locale resources. E.g., "Europe/London"
// for en-GB only contains DST names
if (!exists(namesSuper, INDEX_STD_LONG) && !locale.getCountry().isEmpty()) {
String[] names =
getDisplayNameArray(id, Locale.forLanguageTag(locale.getLanguage()));
if (exists(names, INDEX_STD_LONG)) {
namesSuper[INDEX_STD_LONG] = names[INDEX_STD_LONG];
}
}
for(int i = INDEX_STD_LONG; i < namesSuper.length; i++) { // index 0 is the 'id' itself
switch (namesSuper[i]) {
case "":
// Fill in empty elements
deriveFallbackName(namesSuper, i, locale,
namesSuper[INDEX_DST_LONG].isEmpty());
break;
case NO_INHERITANCE_MARKER:
// CLDR's "no inheritance marker"
namesSuper[i] = toGMTFormat(id, i == INDEX_DST_LONG || i == INDEX_DST_SHORT,
i % 2 != 0, locale);
break;
default:
break;
}
}
return namesSuper;
} else {
// Derive the names for this id. Validate the id first.
if (Arrays.binarySearch(AVAILABLE_IDS.INSTANCE, id) >= 0) {
String[] names = new String[INDEX_GEN_SHORT + 1];
names[INDEX_TZID] = id;
deriveFallbackNames(names, locale);
return names;
}
}
return null;
}
@Override
protected String[][] getZoneStrings(Locale locale) {
// Use English for the ROOT locale
locale = locale.equals(Locale.ROOT) ? Locale.ENGLISH : locale;
String[][] ret = super.getZoneStrings(locale);
// Fill in for the empty names.
// English names are prefilled for performance.
if (locale.getLanguage() != "en") {
for (int zoneIndex = 0; zoneIndex < ret.length; zoneIndex++) {
deriveFallbackNames(ret[zoneIndex], locale);
}
}
return ret;
}
// Derive fallback time zone name according to LDML's logic
private void deriveFallbackNames(String[] names, Locale locale) {
for (int i = INDEX_STD_LONG; i <= INDEX_GEN_SHORT; i++) {
deriveFallbackName(names, i, locale, false);
}
}
private void deriveFallbackName(String[] names, int index, Locale locale, boolean noDST) {
if (exists(names, index)) {
return;
}
// Check if COMPAT can substitute the name
if (LocaleProviderAdapter.getAdapterPreference().contains(Type.JRE)) {
String[] compatNames = (String[])LocaleProviderAdapter.forJRE()
.getLocaleResources(locale)
.getTimeZoneNames(names[INDEX_TZID]);
if (compatNames != null) {
for (int i = INDEX_STD_LONG; i <= INDEX_GEN_SHORT; i++) {
// Assumes COMPAT has no empty slots
if (i == index || !exists(names, i)) {
names[i] = compatNames[i];
}
}
return;
}
}
// Type Fallback
if (noDST && typeFallback(names, index)) {
return;
}
// Region Fallback
if (regionFormatFallback(names, index, locale)) {
return;
}
// last resort
String id = names[INDEX_TZID].toUpperCase(Locale.ROOT);
if (!id.startsWith("ETC/GMT") &&
!id.startsWith("GMT") &&
!id.startsWith("UT")) {
names[index] = toGMTFormat(names[INDEX_TZID],
index == INDEX_DST_LONG || index == INDEX_DST_SHORT,
index % 2 != 0,
locale);
}
}
private boolean exists(String[] names, int index) {
return Objects.nonNull(names)
&& Objects.nonNull(names[index])
&& !names[index].isEmpty();
}
private boolean typeFallback(String[] names, int index) {
// check generic
int genIndex = INDEX_GEN_SHORT - index % 2;
if (!exists(names, index) && exists(names, genIndex)) {
names[index] = names[genIndex];
} else {
// check standard
int stdIndex = INDEX_STD_SHORT - index % 2;
if (!exists(names, index) && exists(names, stdIndex)) {
names[index] = names[stdIndex];
}
}
return exists(names, index);
}
private boolean regionFormatFallback(String[] names, int index, Locale l) {
String id = names[INDEX_TZID];
LocaleResources lr = LocaleProviderAdapter.forType(Type.CLDR).getLocaleResources(l);
ResourceBundle fd = lr.getJavaTimeFormatData();
String rgn = (String) lr.getTimeZoneNames("timezone.excity." + id);
if (rgn == null && !id.startsWith("Etc") && !id.startsWith("SystemV")) {
int slash = id.lastIndexOf('/');
if (slash > 0) {
rgn = id.substring(slash + 1).replaceAll("_", " ");
}
}
if (rgn != null) {
String fmt = "";
switch (index) {
case INDEX_STD_LONG:
fmt = fd.getString("timezone.regionFormat.standard");
break;
case INDEX_DST_LONG:
fmt = fd.getString("timezone.regionFormat.daylight");
break;
case INDEX_GEN_LONG:
fmt = fd.getString("timezone.regionFormat");
break;
}
if (!fmt.isEmpty()) {
names[index] = MessageFormat.format(fmt, rgn);
}
}
return exists(names, index);
}
private String toGMTFormat(String id, boolean daylight, boolean isShort, Locale l) {
TimeZone tz = ZoneInfoFile.getZoneInfo(id);
int offset = (tz.getRawOffset() + (daylight ? tz.getDSTSavings() : 0)) / 60000;
LocaleResources lr = LocaleProviderAdapter.forType(Type.CLDR).getLocaleResources(l);
ResourceBundle fd = lr.getJavaTimeFormatData();
if (offset == 0) {
return fd.getString("timezone.gmtZeroFormat");
} else {
String gmtFormat = fd.getString("timezone.gmtFormat");
String hourFormat = fd.getString("timezone.hourFormat");
if (offset > 0) {
hourFormat = hourFormat.substring(0, hourFormat.indexOf(";"));
} else {
hourFormat = hourFormat.substring(hourFormat.indexOf(";") + 1);
offset = -offset;
}
hourFormat = hourFormat
.replaceFirst("H+", (isShort ? "\\%1\\$d" : "\\%1\\$02d"))
.replaceFirst("m+", "\\%2\\$02d");
return MessageFormat.format(gmtFormat,
String.format(hourFormat, offset / 60, offset % 60));
}
}
}