com.edgenius.core.webapp.filter.LocaleFilter.java Source code

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Here is the source code for com.edgenius.core.webapp.filter.LocaleFilter.java

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/* 
 * =============================================================
 * Copyright (C) 2007-2011 Edgenius (http://www.edgenius.com)
 * =============================================================
 * License Information: http://www.edgenius.com/licensing/edgenius/2.0/
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2.0
 * as published by the Free Software Foundation.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 *
 * http://www.gnu.org/licenses/gpl.txt
 *  
 * ****************************************************************
 */
package com.edgenius.core.webapp.filter;

import java.io.IOException;
import java.util.Locale;
import java.util.TimeZone;

import javax.servlet.FilterChain;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import javax.servlet.jsp.jstl.core.Config;

import org.apache.commons.lang.StringUtils;
import org.springframework.context.ApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;
import org.springframework.web.filter.OncePerRequestFilter;

import com.edgenius.core.Constants;
import com.edgenius.core.Global;
import com.edgenius.core.UserSetting;
import com.edgenius.core.model.User;
import com.edgenius.core.service.LocaleContextConfHolder;
import com.edgenius.core.service.UserReadingService;

/**
 * LocalFilter request to preferred locale according to user option in database, client browser locale or default locale.
 * The proity is user setting in database is highest, then browser locale, then the default locale. 
 * <p> 
 * This filter also setup Text Direction and TimeZone.
 * 
 * @author Dapeng.Ni
 * 
 */
public class LocaleFilter extends OncePerRequestFilter {
    /**
     * 
     */
    private static final String PREFERRED_LOCALE = "PreferredLocale";

    //   private static final Logger log = LoggerFactory.getLogger(LocaleFilter.class);

    private String encoding;

    private UserReadingService userReadingService = null;

    /**
     * Set the encoding to use for requests. This encoding will be
     * passed into a ServletRequest.setCharacterEncoding call.
    */
    public void setEncoding(String encoding) {
        this.encoding = encoding;
    }

    public void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain chain)
            throws IOException, ServletException {
        //       if(log.isDebugEnabled()){
        //          log.debug("Request URL: " + request.getRequestURI());
        //       }

        //charset encoding
        if (!StringUtils.isEmpty(this.encoding))
            request.setCharacterEncoding(encoding);
        else
            request.setCharacterEncoding(Constants.UTF8);

        String direction = null;
        Locale preferredLocale = null;
        TimeZone timezone = null;
        HttpSession session = request.getSession(false);
        if (getUserService() != null) { //for Install mode, it will return null
            User user = getUserService().getUserByName(request.getRemoteUser());
            if (user != null && !user.isAnonymous()) {
                //locale
                UserSetting set = user.getSetting();
                String userLang = set.getLocaleLanguage();
                String userCountry = set.getLocaleCountry();
                if (userLang != null && userCountry != null) {
                    preferredLocale = new Locale(userLang, userCountry);
                }
                //text direction in HTML 
                direction = set.getDirection();
                //timezone
                if (set.getTimeZone() != null)
                    timezone = TimeZone.getTimeZone(set.getTimeZone());
            }
        }
        if (preferredLocale == null) {
            if (Global.DetectLocaleFromRequest) {
                Locale locale = request.getLocale();
                if (locale != null) {
                    preferredLocale = locale;
                }
            }
            if (preferredLocale == null) {
                preferredLocale = Global.getDefaultLocale();
            }
        }

        if (direction == null) {
            direction = Global.DefaultDirection;
        }

        if (timezone == null) {
            if (session != null) {
                //try to get timezone from HttpSession, which will be intial set in SecurityControllerImpl.checkLogin() method
                timezone = (TimeZone) session.getAttribute(Constants.TIMEZONE);
            }
            if (timezone == null)
                timezone = TimeZone.getTimeZone(Global.DefaultTimeZone);
        }

        //set locale for STURTS and JSTL
        // set the time zone - must be set for dates to display the time zone
        if (session != null) {
            Config.set(session, Config.FMT_LOCALE, preferredLocale);
            session.setAttribute(Constants.DIRECTION, direction);
            Config.set(session, Config.FMT_TIME_ZONE, timezone);
        }

        //replace request by LocaleRequestWrapper
        if (!(request instanceof LocaleRequestWrapper)) {
            request = new LocaleRequestWrapper(request, preferredLocale);
            LocaleContextConfHolder.setLocale(preferredLocale);
        }

        if (chain != null) {
            request.setAttribute(PREFERRED_LOCALE, preferredLocale.toString());
            chain.doFilter(request, response);
        }
        // Reset thread-bound LocaleContext.
        LocaleContextConfHolder.setLocaleContext(null);
    }

    private UserReadingService getUserService() {
        if (userReadingService == null) {
            ApplicationContext ctx = WebApplicationContextUtils
                    .getRequiredWebApplicationContext(getServletContext());
            try {
                userReadingService = (UserReadingService) ctx.getBean(UserReadingService.SERVICE_NAME);
            } catch (Exception e) {
                return null;
            }
        }
        return userReadingService;
    }

}