com.vmware.xenon.common.SupportedLocales Maven / Gradle / Ivy
/*
* Copyright (c) 2014-2015 VMware, Inc. All Rights Reserved.
*
* 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.vmware.xenon.common;
import java.io.File;
import java.io.FilenameFilter;
import java.io.IOException;
import java.net.URISyntaxException;
import java.net.URL;
import java.nio.file.FileSystem;
import java.nio.file.FileSystems;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.Collections;
import java.util.HashMap;
import java.util.Locale;
import java.util.Map;
import java.util.logging.Logger;
public class SupportedLocales {
private static final String MESSAGES_BASE_FILENAME = "messages_";
private static final String MESSAGES_FOLDER = "i18n";
private static final CharSequence PROPERTIES_SUFFIX = ".properties";
private static Map supportedLocales = loadSupportedLocales();
private SupportedLocales() {
}
public static boolean isSupported(Locale locale) {
return supportedLocales.get(locale.toString()) != null;
}
private static Map loadSupportedLocales() {
String[] messageFiles = getMessageFiles();
Map supportedLocales = new HashMap<>(messageFiles.length);
for (String messageFile : messageFiles) {
Locale locale = parseLocale(messageFile);
supportedLocales.put(locale.toString(), locale);
}
return supportedLocales;
}
private static String[] getMessageFiles() {
URL url = LocalizationUtil.class.getClassLoader().getResource(MESSAGES_FOLDER);
String[] messageFiles = null;
if ("file".equals(url.getProtocol())) {
try {
messageFiles = new File(url.toURI()).list(new FilenameFilter() {
@Override
public boolean accept(File dir, String name) {
return name.contains(MESSAGES_BASE_FILENAME);
}
});
} catch (URISyntaxException e) {
Logger.getAnonymousLogger().warning(
String.format("Unable to load message files from %s: %s ", url, e));
}
} else if ("jar".equals(url.getProtocol())) {
try (FileSystem fileSystem = FileSystems.newFileSystem(url.toURI(),
Collections.emptyMap())) {
Path myPath = fileSystem.getPath(MESSAGES_FOLDER);
messageFiles = Files.walk(myPath, 1)
.filter(path -> path.toString().contains(MESSAGES_BASE_FILENAME))
.map(path -> path.getFileName().toString())
.toArray(String[]::new);
} catch (IOException | URISyntaxException e) {
Logger.getAnonymousLogger().warning(
String.format("Unable to load message files from %s: %s ", url, e));
}
}
if (messageFiles == null) {
messageFiles = new String[0];
}
return messageFiles;
}
private static Locale parseLocale(String messageFilename) {
String localeValue = messageFilename.replace(MESSAGES_BASE_FILENAME, "")
.replace(PROPERTIES_SUFFIX, "");
Locale locale = null;
if (localeValue.isEmpty()) {
locale = LocalizationUtil.DEFAULT_LOCALE;
} else {
localeValue = localeValue.replace("_", "-");
locale = Locale.forLanguageTag(localeValue);
}
if (locale.getLanguage() == null || locale.getLanguage().isEmpty()) {
throw new IllegalArgumentException("No valid Locale could be parsed for: "
+ localeValue);
}
return locale;
}
}