org.opencms.i18n.CmsAcceptLanguageHeaderParser Maven / Gradle / Ivy
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/*
* This library is part of OpenCms -
* the Open Source Content Management System
*
* Copyright (c) Alkacon Software GmbH & Co. KG (http://www.alkacon.com)
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* For further information about Alkacon Software GmbH & Co. KG, please see the
* company website: http://www.alkacon.com
*
* For further information about OpenCms, please see the
* project website: http://www.opencms.org
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* This file is based on:
* org.apache.fulcrum.localization.LocaleTokenizer
* from the Apache Fulcrum/Turbine project.
*
* The Apache Software License, Version 1.1
*
* Copyright (c) 2001 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Apache" and "Apache Software Foundation" and
* "Apache Turbine" must not be used to endorse or promote products
* derived from this software without prior written permission. For
* written permission, please contact [email protected].
*
* 5. Products derived from this software may not be called "Apache",
* "Apache Turbine", nor may "Apache" appear in their name, without
* prior written permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation. For more
* information on the Apache Software Foundation, please see
* Accept-Language header as per section 14.4 of RFC 2068
* (HTTP 1.1 header field definitions) and creates a sorted list of Locales from it.
*
* @since 6.0.0
*/
public class CmsAcceptLanguageHeaderParser {
/**
* Struct representing an element of the HTTP Accept-Language header.
*/
protected static class AcceptLanguage implements Comparable {
/** The language and country. */
Locale m_locale;
/** The m_quality of our m_locale (as values approach 1.0, they indicate increased user preference). */
Float m_quality = DEFAULT_QUALITY;
/**
* @see java.lang.Comparable#compareTo(java.lang.Object)
*/
public final int compareTo(AcceptLanguage acceptLang) {
return m_quality.compareTo((acceptLang).m_quality);
}
/**
* @see java.lang.Object#equals(java.lang.Object)
*/
@Override
public boolean equals(Object obj) {
if (obj == this) {
return true;
}
if (obj instanceof AcceptLanguage) {
AcceptLanguage other = (AcceptLanguage)obj;
return m_locale.equals(other.m_locale) && (m_quality.floatValue() == other.m_quality.floatValue());
}
return false;
}
/**
* @see java.lang.Object#hashCode()
*/
@Override
public int hashCode() {
return m_locale.hashCode() * (int)(m_quality.floatValue() * 1117.0);
}
}
/** A constant for the HTTP Accept-Language header. */
public static final String ACCEPT_LANGUAGE = "Accept-Language";
/** The default m_quality value for an AcceptLanguage object. */
protected static final Float DEFAULT_QUALITY = new Float(1.0f);
/** Separates elements of the Accept-Language HTTP header. */
private static final char LOCALE_SEPARATOR = ',';
/** Separates m_locale from m_quality within elements. */
private static final char QUALITY_SEPARATOR = ';';
/** The parsed Accept-Language headers. */
private List m_acceptLanguage = new ArrayList(3);
/** The parsed locales. */
private List m_locales;
/**
* Parses the Accept-Language header from the provided request.
*
* @param req the request to parse
* @param defaultLocale the default locale to use
*/
public CmsAcceptLanguageHeaderParser(HttpServletRequest req, Locale defaultLocale) {
this(req.getHeader(ACCEPT_LANGUAGE), defaultLocale);
}
/**
* Parses the Accept-Language header.
*
* @param header the Accept-Language header (i.e. en, es;q=0.8, zh-TW;q=0.1)
* @param defaultLocale the default locale to use
*/
public CmsAcceptLanguageHeaderParser(String header, Locale defaultLocale) {
// check if there was a locale foud in the HTTP header.
// if not, use the default locale.
if (header == null) {
m_locales = new ArrayList();
m_locales.add(defaultLocale);
} else {
List tokens = CmsStringUtil.splitAsList(header, LOCALE_SEPARATOR, true);
Iterator it = tokens.iterator();
while (it.hasNext()) {
AcceptLanguage acceptLang = new AcceptLanguage();
String element = it.next();
int index;
// Record and cut off any quality value that comes after a semi-colon.
index = element.indexOf(QUALITY_SEPARATOR);
if (index != -1) {
String q = element.substring(index);
element = element.substring(0, index);
index = q.indexOf('=');
if (index != -1) {
try {
acceptLang.m_quality = Float.valueOf(q.substring(index + 1));
} catch (NumberFormatException useDefault) {
// noop
}
}
}
element = element.trim();
// Create a Locale from the language. A dash may separate the language from the country.
index = element.indexOf('-');
if (index == -1) {
// No dash means no country.
acceptLang.m_locale = new Locale(element, "");
} else {
acceptLang.m_locale = new Locale(element.substring(0, index), element.substring(index + 1));
}
m_acceptLanguage.add(acceptLang);
}
// sort by quality in descending order
Collections.sort(m_acceptLanguage, Collections.reverseOrder());
// store all calculated Locales in a List
m_locales = new ArrayList(m_acceptLanguage.size());
Iterator i = m_acceptLanguage.iterator();
while (i.hasNext()) {
AcceptLanguage lang = i.next();
m_locales.add(lang.m_locale);
}
}
}
/**
* Creates a value string for the HTTP Accept-Language header based on the default localed.
*
* @return value string for the HTTP Accept-Language
*/
public static String createLanguageHeader() {
String header;
// get the default accept-language header value
List defaultLocales = OpenCms.getLocaleManager().getDefaultLocales();
Iterator i = defaultLocales.iterator();
header = "";
while (i.hasNext()) {
Locale loc = i.next();
header += loc.getLanguage() + ", ";
}
header = header.substring(0, header.length() - 2);
return header;
}
/**
* Returns the sorted list of accepted Locales.
*
* @return the sorted list of accepted Locales
*/
public List getAcceptedLocales() {
return m_locales;
}
}