/*
* =============================================================================
*
* Copyright (c) 2011-2014, The THYMELEAF team (http://www.thymeleaf.org)
*
* 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.thymeleaf.spring4.view;
import java.io.IOException;
import java.util.Locale;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.js.ajax.AjaxHandler;
import org.springframework.js.ajax.SpringJavascriptAjaxHandler;
import org.springframework.web.servlet.View;
import org.springframework.web.servlet.view.RedirectView;
import org.thymeleaf.exceptions.ConfigurationException;
/**
* <p>
* Subclass of {@link ThymeleafViewResolver} adding compatibility with AJAX-based events
* (redirects) in Spring WebFlow.
* </p>
* <p>
* <b>Important</b>: Spring WebFlow dependencies are OPTIONAL. If you are not using WebFlow
* in your application, then you should be using {@link ThymeleafViewResolver} directly.
* </p>
*
* @author Daniel Fernández
*
* @since 2.0.11
*
*/
public class AjaxThymeleafViewResolver
extends ThymeleafViewResolver {
private static final Logger vrlogger = LoggerFactory.getLogger(AjaxThymeleafViewResolver.class);
private AjaxHandler ajaxHandler = new SpringJavascriptAjaxHandler();
public AjaxThymeleafViewResolver() {
super();
}
/**
* <p>
* Return the AJAX handler (from Spring Javascript) used
* to determine whether a request is an AJAX request or not
* in views resolved by this resolver.
* </p>
* <p>
* An instance of {@link SpringJavascriptAjaxHandler} is set by default.
* </p>
*
* @return the AJAX handler.
*/
public AjaxHandler getAjaxHandler() {
return this.ajaxHandler;
}
/**
* <p>
* Sets the AJAX handler (from Spring Javascript) used
* to determine whether a request is an AJAX request or not
* in views resolved by this resolver.
* </p>
* <p>
* An instance of {@link SpringJavascriptAjaxHandler} is set by default.
* </p>
*
* @param ajaxHandler the AJAX handler.
*/
public void setAjaxHandler(final AjaxHandler ajaxHandler) {
this.ajaxHandler = ajaxHandler;
}
@Override
protected View createView(final String viewName, final Locale locale) throws Exception {
if (!canHandle(viewName, locale)) {
return null;
}
if (this.ajaxHandler == null) {
throw new ConfigurationException("[THYMELEAF] AJAX Handler set into " +
AjaxThymeleafViewResolver.class.getSimpleName() + " instance is null.");
}
// Check for special "redirect:" prefix.
if (viewName.startsWith(REDIRECT_URL_PREFIX)) {
vrlogger.trace(
"[THYMELEAF] View {} is a redirect. An AJAX-enabled RedirectView implementation will " +
"be handling the request.", viewName);
final String redirectUrl = viewName.substring(REDIRECT_URL_PREFIX.length());
return new AjaxRedirectView(
this.ajaxHandler, redirectUrl, isRedirectContextRelative(), isRedirectHttp10Compatible());
}
final View view = super.createView(viewName, locale);
if (view instanceof AjaxEnabledView) {
// Set the AJAX handler into view, if it is an AjaxThymeleafView.
final AjaxEnabledView ajaxEnabledView = (AjaxEnabledView) view;
if (ajaxEnabledView.getAjaxHandler() == null && getAjaxHandler() != null) {
ajaxEnabledView.setAjaxHandler(getAjaxHandler());
}
}
return view;
}
private static class AjaxRedirectView extends RedirectView {
private static final Logger vlogger = LoggerFactory.getLogger(AjaxRedirectView.class);
private AjaxHandler ajaxHandler = new SpringJavascriptAjaxHandler();
AjaxRedirectView(final AjaxHandler ajaxHandler, final String redirectUrl,
final boolean redirectContextRelative, final boolean redirectHttp10Compatible) {
super(redirectUrl, redirectContextRelative, redirectHttp10Compatible);
this.ajaxHandler = ajaxHandler;
}
@Override
protected void sendRedirect(final HttpServletRequest request, final HttpServletResponse response,
final String targetUrl, final boolean http10Compatible)
throws IOException {
if (this.ajaxHandler == null) {
throw new ConfigurationException("[THYMELEAF] AJAX Handler set into " +
AjaxThymeleafViewResolver.class.getSimpleName() + " instance is null.");
}
if (this.ajaxHandler.isAjaxRequest(request, response)) {
if (vlogger.isTraceEnabled()) {
vlogger.trace(
"[THYMELEAF] RedirectView for URL \"{}\" is an AJAX request. AjaxHandler of class {} " +
"will be in charge of processing the request.", targetUrl, this.ajaxHandler.getClass().getName());
}
this.ajaxHandler.sendAjaxRedirect(targetUrl, request, response, false);
} else {
vlogger.trace(
"[THYMELEAF] RedirectView for URL \"{}\" is not an AJAX request. Request will be handled " +
"as a normal redirect", targetUrl);
super.sendRedirect(request, response, targetUrl, http10Compatible);
}
}
}
}