/* I18Ns.java
{{IS_NOTE
Purpose:
Description:
History:
Thu Jul 13 16:53:47 2006, Created by tomyeh
}}IS_NOTE
Copyright (C) 2006 Potix Corporation. All Rights Reserved.
{{IS_RIGHT
}}IS_RIGHT
*/
package org.zkoss.zk.ui.http;
import java.util.TimeZone;
import javax.servlet.ServletContext;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpSession;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.zkoss.lang.Classes;
import org.zkoss.lang.Library;
import org.zkoss.text.DateFormatInfo;
import org.zkoss.text.DateFormats;
import org.zkoss.util.TimeZones;
import org.zkoss.web.Attributes;
import org.zkoss.web.servlet.Charsets;
import org.zkoss.zk.ui.Session;
import org.zkoss.zk.ui.sys.SessionsCtrl;
/**
* Internationalization utilities.
*
* <p>Typical use:
* <pre><code>
Object old = I18Ns.setup(session, request, response);
try {
...
} finally {
I18Ns.cleanup(old);
}
*</code></pre>
* @author tomyeh
*/
public class I18Ns {
private static final Logger log = LoggerFactory.getLogger(I18Ns.class);
private static final String ATTR_SETUP = "org.zkoss.zk.ui.http.charset.setup";
/** Sets up the internationalization attributes, including locale
* and time zone.
*
* @param sess the session. It cannot be null.
* @param charset the response's charset. If null or empty,
* response.setCharacterEncoding won't be called, i.e., the container's
* default is used.
*/
public static final Object setup(Session sess, ServletRequest request, ServletResponse response, String charset) {
return setup((Object) sess, request, response, charset);
}
/** Sets up the internationalization attributes, including locale
* and time zone.
*
* <p>This method is used only for requests that don't
* count on {@link Session}.
*
* <ol>
* <li>This method first checks if any session attribute called
* {@link Attributes#PREFERRED_LOCALE} and
* {@link Attributes#PREFERRED_TIME_ZONE} are set with the preferred
* locale and timezone. If so, use it as the default.</li>
* <li>Then, it checks if any servlet context attribute called
* {@link Attributes#PREFERRED_LOCALE} and
* {@link Attributes#PREFERRED_TIME_ZONE} are set with the preferred
* locale and timezone. If so, use it as the default.</li>
* <li>Then, it checks if any library properties called
* {@link Attributes#PREFERRED_LOCALE} and
* {@link Attributes#PREFERRED_TIME_ZONE} are set with the preferred
* locale and timezone. If so, use it as the default.</li>
* <li>Otherwise, it depends the setting and location of the browser
* (by checking the request's header).</li>
* </ol>
*
* @param sess the HTTP session. It cannot be null.
* @param charset the response's charset. If null or empty,
* response.setCharacterEncoding won't be called, i.e., the container's
* default is used.
* @since 3.6.2
*/
public static final Object setup(HttpSession sess, ServletRequest request, ServletResponse response,
String charset) {
return setup((Object) sess, request, response, charset);
}
private static final Object setup(Object sess, ServletRequest request, ServletResponse response, String charset) {
final Object[] old;
if (request.getAttribute(ATTR_SETUP) != null) { //has been setup
old = null;
} else {
final HttpSession hsess;
if (sess instanceof Session) {
final Session se = (Session) sess;
//Invoke the request interceptors
se.getWebApp().getConfiguration().invokeRequestInterceptors(se, request, response);
hsess = (HttpSession) se.getNativeSession();
} else {
hsess = (HttpSession) sess;
}
final Object ol = Charsets.setup(hsess, request, response, charset);
//Charsets will handle PREFERRED_LOCALE
//time zone
final TimeZone tz = getTimeZone(hsess);
final Object otz = TimeZones.setThreadLocal(tz);
//date format info
final DateFormatInfo dfinfo = getDateFormatInfo(hsess);
final Object odi = DateFormats.setLocalFormatInfo(dfinfo);
request.setAttribute(ATTR_SETUP, Boolean.TRUE); //mark as setup
old = new Object[] { ol, otz, odi };
}
if (sess instanceof Session)
SessionsCtrl.setCurrent((Session) sess);
return old;
}
/** Returns the time zone of the given session, or null if not set.
*/
private static TimeZone getTimeZone(HttpSession hsess) {
TimeZone tz = checkTimeZone(hsess.getAttribute(Attributes.PREFERRED_TIME_ZONE));
if (tz != null)
return tz;
tz = checkTimeZone(hsess.getAttribute(PX_PREFERRED_TIME_ZONE)); //backward compatible (prior to 5.0.3)
if (tz != null)
return tz;
tz = checkTimeZone(hsess.getServletContext().getAttribute(Attributes.PREFERRED_TIME_ZONE));
if (tz != null)
return tz;
tz = checkTimeZone(hsess.getServletContext().getAttribute(PX_PREFERRED_TIME_ZONE)); //backward compatible (prior to 5.0.3)
if (tz != null)
return tz;
String s = Library.getProperty(Attributes.PREFERRED_TIME_ZONE);
return s != null ? TimeZone.getTimeZone(s) : null;
}
/** Returns the format info of the given session, or null if not set.
*/
private static DateFormatInfo getDateFormatInfo(HttpSession hsess) {
DateFormatInfo fi = checkDateFormatInfo(hsess.getAttribute(Attributes.PREFERRED_DATE_FORMAT_INFO));
if (fi != null)
return fi;
fi = checkDateFormatInfo(hsess.getServletContext().getAttribute(Attributes.PREFERRED_DATE_FORMAT_INFO));
if (fi != null)
return fi;
String s = Library.getProperty(Attributes.PREFERRED_DATE_FORMAT_INFO);
if (s != null)
try {
return checkDateFormatInfo(Classes.newInstanceByThread(s));
} catch (Throwable ex) {
log.error("Failed to instantiate " + s, ex);
}
return null;
}
/** The previous attribute name (backward compatible prior to 5.0.3. */
private static final String PX_PREFERRED_TIME_ZONE = "px_preferred_time_zone";
private static TimeZone checkTimeZone(Object tz) {
if (tz != null && !(tz instanceof TimeZone)) {
log.warn(Attributes.PREFERRED_TIME_ZONE + " ignored. TimeZone required, not " + tz.getClass());
return null;
}
return (TimeZone) tz;
}
private static DateFormatInfo checkDateFormatInfo(Object o) {
if (o == null || (o instanceof DateFormatInfo))
return (DateFormatInfo) o;
try {
if (o instanceof String)
o = Classes.forNameByThread((String) o);
if (o instanceof Class)
return (DateFormatInfo) ((Class) o).newInstance();
} catch (Throwable ex) {
log.warn(Attributes.PREFERRED_DATE_FORMAT_INFO + " ignored. Failed to instantiate " + o, ex);
return null;
}
log.warn(Attributes.PREFERRED_DATE_FORMAT_INFO + " ignored. DateFormatInfo required, not " + o.getClass());
return null;
}
/* Cleans up the internationalization attributes.
*
* @param old which must be the value returned by setup.
*/
public static final void cleanup(ServletRequest request, Object old) {
if (old != null) {
request.removeAttribute(ATTR_SETUP);
SessionsCtrl.setCurrent((Session) null);
final Object[] op = (Object[]) old;
TimeZones.setThreadLocal((TimeZone) op[1]);
DateFormats.setLocalFormatInfo((DateFormatInfo) op[2]);
Charsets.cleanup(request, op[0]);
}
}
/** Sets the preferred timezone for the specified session.
* It is the default timezone for the whole Web session.
* <p>Default: null (no preferred timezone -- depending on browser's location).
* @param timezone the preferred time zone. If null, it means no preferred timezone
* @see #setup
* @since 3.6.3
*/
public static final void setPreferredTimeZone(HttpSession hsess, TimeZone timezone) {
if (timezone != null) {
hsess.setAttribute(Attributes.PREFERRED_TIME_ZONE, timezone);
} else {
hsess.removeAttribute(Attributes.PREFERRED_TIME_ZONE);
hsess.removeAttribute(PX_PREFERRED_TIME_ZONE);
}
}
/** Sets the preferred timezone for the specified servlet context.
* It is the default timezone for the whole Web application.
* <p>Default: null (no preferred timezone -- depending on browser's location).
* @param timezone the preferred time zone. If null, it means no preferred timezone
* @see #setup
* @since 3.6.3
*/
public static final void setPreferredTimeZone(ServletContext ctx, TimeZone timezone) {
if (timezone != null) {
ctx.setAttribute(Attributes.PREFERRED_TIME_ZONE, timezone);
} else {
ctx.removeAttribute(Attributes.PREFERRED_TIME_ZONE);
ctx.removeAttribute(PX_PREFERRED_TIME_ZONE);
}
}
}