org.springframework.web.context.request.RequestContextListener Maven / Gradle / Ivy
/*
* Copyright 2002-2007 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 org.springframework.web.context.request;
import javax.servlet.ServletRequestEvent;
import javax.servlet.ServletRequestListener;
import javax.servlet.http.HttpServletRequest;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.context.i18n.LocaleContextHolder;
/**
* Servlet 2.4+ listener that exposes the request to the current thread,
* through both {@link org.springframework.context.i18n.LocaleContextHolder} and
* {@link RequestContextHolder}. To be registered as listener in web.xml.
*
* Alternatively, Spring's {@link org.springframework.web.filter.RequestContextFilter}
* and Spring's {@link org.springframework.web.servlet.DispatcherServlet} also expose
* the same request context to the current thread.
*
*
This listener is mainly for use with third-party servlets, e.g. the JSF FacesServlet.
* Within Spring's own web support, DispatcherServlet's processing is perfectly sufficient.
*
* @author Juergen Hoeller
* @author Steven Devijver
* @since 2.0
* @see javax.servlet.ServletRequestListener
* @see org.springframework.context.i18n.LocaleContextHolder
* @see org.springframework.web.context.request.RequestContextHolder
* @see org.springframework.web.filter.RequestContextFilter
* @see org.springframework.web.servlet.DispatcherServlet
*/
public class RequestContextListener implements ServletRequestListener {
private static final String REQUEST_ATTRIBUTES_ATTRIBUTE =
RequestContextListener.class.getName() + ".REQUEST_ATTRIBUTES";
/** Logger available to subclasses */
protected final Log logger = LogFactory.getLog(getClass());
public void requestInitialized(ServletRequestEvent requestEvent) {
if (!(requestEvent.getServletRequest() instanceof HttpServletRequest)) {
throw new IllegalArgumentException(
"Request is not an HttpServletRequest: " + requestEvent.getServletRequest());
}
HttpServletRequest request = (HttpServletRequest) requestEvent.getServletRequest();
ServletRequestAttributes attributes = new ServletRequestAttributes(request);
request.setAttribute(REQUEST_ATTRIBUTES_ATTRIBUTE, attributes);
LocaleContextHolder.setLocale(request.getLocale());
RequestContextHolder.setRequestAttributes(attributes);
if (logger.isDebugEnabled()) {
logger.debug("Bound request context to thread: " + request);
}
}
public void requestDestroyed(ServletRequestEvent requestEvent) {
ServletRequestAttributes attributes =
(ServletRequestAttributes) requestEvent.getServletRequest().getAttribute(REQUEST_ATTRIBUTES_ATTRIBUTE);
ServletRequestAttributes threadAttributes =
(ServletRequestAttributes) RequestContextHolder.getRequestAttributes();
if (threadAttributes != null) {
// We're assumably within the original request thread...
if (attributes == null) {
attributes = threadAttributes;
}
RequestContextHolder.setRequestAttributes(null);
LocaleContextHolder.setLocale(null);
}
if (attributes != null) {
attributes.requestCompleted();
if (logger.isDebugEnabled()) {
logger.debug("Cleared thread-bound request context: " + requestEvent.getServletRequest());
}
}
}
}