/*
* Copyright 2010 the original author or authors.
*
* 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 com.springsource.greenhouse.home;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.joda.time.DateTimeZone;
import org.springframework.format.datetime.joda.JodaTimeContext;
import org.springframework.format.datetime.joda.JodaTimeContextHolder;
import org.springframework.web.servlet.HandlerInterceptor;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.util.WebUtils;
/**
* Spring MVC Interceptor that sets the request's {@link DateTimeZone} from a cookie.
* Allows the client's timezone to be figured out by JavaScript, then submitted and applied on the server as the default timezone for the request.
* Useful when you need to render dates in client local time.
* @author Keith Donald
*/
public class DateTimeZoneHandlerInterceptor implements HandlerInterceptor {
public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
JodaTimeContext context = new JodaTimeContext();
context.setTimeZone(getTimeZone(request));
JodaTimeContextHolder.setJodaTimeContext(context);
return true;
}
public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
if (modelAndView != null) {
modelAndView.addObject("jodaTimeContext", JodaTimeContextHolder.getJodaTimeContext());
}
}
public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
JodaTimeContextHolder.resetJodaTimeContext();
}
// interna helpers
private DateTimeZone getTimeZone(HttpServletRequest request) {
Integer millisOffset = getMillisOffset(request);
if (millisOffset != null) {
try {
return DateTimeZone.forOffsetMillis(millisOffset);
} catch (IllegalArgumentException e) {
return DateTimeZone.getDefault();
}
} else {
return DateTimeZone.getDefault();
}
}
private Integer getMillisOffset(HttpServletRequest request) {
Cookie cookie = WebUtils.getCookie(request, "Greenhouse.timeZoneOffset");
if (cookie != null ) {
return Integer.valueOf(cookie.getValue());
} else {
return null;
}
}
}