/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.catalina.util;
import java.io.InputStream;
import java.util.Locale;
import java.util.Properties;
import org.apache.tomcat.util.ExceptionUtils;
import org.apache.tomcat.util.compat.JreCompat;
/**
* Utility class that attempts to map from a Locale to the corresponding character set to be used for interpreting input
* text (or generating output text) when the Content-Type header does not include one. You can customize the behavior of
* this class by modifying the mapping data it loads, or by subclassing it (to change the algorithm) and then using your
* own version for a particular web application.
*/
public class CharsetMapper {
// ---------------------------------------------------- Manifest Constants
/**
* Default properties resource name.
*/
public static final String DEFAULT_RESOURCE = "/org/apache/catalina/util/CharsetMapperDefault.properties";
// ---------------------------------------------------------- Constructors
/**
* Construct a new CharsetMapper using the default properties resource.
*/
public CharsetMapper() {
this(DEFAULT_RESOURCE);
}
/**
* Construct a new CharsetMapper using the specified properties' resource.
*
* @param name Name of a properties resource to be loaded
*
* @exception IllegalArgumentException if the specified properties resource could not be loaded for any reason.
*/
public CharsetMapper(String name) {
if (JreCompat.isGraalAvailable()) {
map.put("en", "ISO-8859-1");
} else {
try (InputStream stream = this.getClass().getResourceAsStream(name)) {
map.load(stream);
} catch (Throwable t) {
ExceptionUtils.handleThrowable(t);
throw new IllegalArgumentException(t);
}
}
}
// ---------------------------------------------------- Instance Variables
/**
* The mapping properties that have been initialized from the specified or default properties resource.
*/
private final Properties map = new Properties();
// ------------------------------------------------------- Public Methods
/**
* Calculate the name of a character set to be assumed, given the specified Locale and the absence of a character
* set specified as part of the content type header.
*
* @param locale The locale for which to calculate a character set
*
* @return the charset name
*/
public String getCharset(Locale locale) {
// Match full language_country_variant first, then language_country,
// then language only
String charset = map.getProperty(locale.toString());
if (charset == null) {
charset = map.getProperty(locale.getLanguage() + "_" + locale.getCountry());
if (charset == null) {
charset = map.getProperty(locale.getLanguage());
}
}
return charset;
}
/**
* The deployment descriptor can have a locale-encoding-mapping-list element which describes the webapp's desired
* mapping from locale to charset. This method gets called when processing the web.xml file for a context
*
* @param locale The locale for a character set
* @param charset The charset to be associated with the locale
*/
public void addCharsetMappingFromDeploymentDescriptor(String locale, String charset) {
map.put(locale, charset);
}
}