/***
* Copyright (c) 2009 Caelum - www.caelum.com.br/opensource
* 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 br.com.caelum.vraptor.core;
import java.text.MessageFormat;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.ResourceBundle;
import javax.servlet.ServletContext;
import javax.servlet.jsp.jstl.core.Config;
import javax.servlet.jsp.jstl.fmt.LocalizationContext;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import br.com.caelum.vraptor.ioc.RequestScoped;
import br.com.caelum.vraptor.util.EmptyBundle;
import com.google.common.base.Strings;
/**
* The default implementation of bundle provider uses JSTL's api to access user information on the bundle to be used.
*
* @author Guilherme Silveira
* @author Otávio Scherer Garcia
*/
@RequestScoped
public class JstlLocalization
implements Localization {
private static final Logger logger = LoggerFactory.getLogger(JstlLocalization.class);
private static final String DEFAULT_BUNDLE_NAME = "messages";
private final RequestInfo request;
private ResourceBundle bundle;
public JstlLocalization(RequestInfo request) {
this.request = request;
}
public ResourceBundle getBundle() {
if (bundle == null) {
initializeBundle();
}
return bundle;
}
/**
* Find the bundle. If the bundle is not found, return an empty for safety operations (avoid
* {@link MissingResourceException}.
*/
private void initializeBundle() {
Object bundle = findByKey(Config.FMT_LOCALIZATION_CONTEXT);
ResourceBundle unsafe = extractUnsafeBundle(bundle);
this.bundle = new SafeResourceBundle(unsafe);
}
private ResourceBundle extractUnsafeBundle(Object bundle) {
if (bundle instanceof String || bundle == null) {
String baseName = (bundle == null) ? DEFAULT_BUNDLE_NAME : bundle.toString();
try {
return ResourceBundle.getBundle(baseName, getLocale());
} catch (MissingResourceException e) {
logger.debug("couldn't find message bundle, creating an empty one");
return new EmptyBundle();
}
}
if (bundle instanceof LocalizationContext) {
return ((LocalizationContext) bundle).getResourceBundle();
}
logger.warn("Can't handle bundle {}. Please report this bug. Using an empty bundle", bundle);
return new EmptyBundle();
}
public Locale getLocale() {
return localeFor(Config.FMT_LOCALE);
}
public Locale getFallbackLocale() {
return localeFor(Config.FMT_FALLBACK_LOCALE);
}
private Locale localeFor(String key) {
Object localeValue = findByKey(key);
if (localeValue instanceof String) {
return findLocalefromString((String) localeValue);
} else if (localeValue instanceof Locale) {
return (Locale) localeValue;
}
return request.getRequest().getLocale();
}
/**
* Looks up a configuration variable in the request, session and application scopes. If none is found, return by
* {@link ServletContext#getInitParameter(String)} method.
*
* @param key
* @return
*/
private Object findByKey(String key) {
Object value = Config.get(request.getRequest(), key);
if (value != null) {
return value;
}
value = Config.get(request.getRequest().getSession(), key);
if (value != null) {
return value;
}
value = Config.get(request.getServletContext(), key);
if (value != null) {
return value;
}
return request.getServletContext().getInitParameter(key);
}
public String getMessage(String key, Object... parameters) {
try {
String content = getBundle().getString(key);
return MessageFormat.format(content, parameters);
} catch (MissingResourceException e) {
return "???" + key + "???";
}
}
/**
* Converts a locale string to {@link Locale}. If the input string is null or empty, return an empty {@link Locale}.
*
* @param str
* @return
*/
private Locale findLocalefromString(String str) {
if (!Strings.isNullOrEmpty(str)) {
String[] arr = str.split("_");
if (arr.length == 1) {
return new Locale(arr[0]);
} else if (arr.length == 2) {
return new Locale(arr[0], arr[1]);
} else {
return new Locale(arr[0], arr[1], arr[2]);
}
}
return null;
}
}