/*
* Copyright 2002-2009 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.servlet.view.feed;
import java.util.List;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.sun.syndication.feed.WireFeed;
import com.sun.syndication.feed.rss.Channel;
import com.sun.syndication.feed.rss.Item;
/**
* Abstract superclass for RSS Feed views, using java.net's
* <a href="https://rome.dev.java.net/">ROME</a> package.
*
* <p>Application-specific view classes will extend this class.
* The view will be held in the subclass itself, not in a template.
*
* <p>Main entry points are the {@link #buildFeedMetadata(Map, WireFeed , HttpServletRequest)}
* and {@link #buildFeedItems(Map, HttpServletRequest, HttpServletResponse)}.
*
* <p>Thanks to Jettro Coenradie and Sergio Bossa for the original feed view prototype!
*
* @author Arjen Poutsma
* @author Juergen Hoeller
* @since 3.0
* @see #buildFeedMetadata(Map, WireFeed , HttpServletRequest)
* @see #buildFeedItems(Map, HttpServletRequest, HttpServletResponse)
*/
public abstract class AbstractRssFeedView extends AbstractFeedView<Channel> {
public AbstractRssFeedView() {
setContentType("application/rss+xml");
}
/**
* Create a new Channel instance to hold the entries.
* <p>By default returns an RSS 2.0 channel, but the subclass can specify any channel.
*/
@Override
protected Channel newFeed() {
return new Channel("rss_2.0");
}
/**
* Invokes {@link #buildFeedItems(Map, HttpServletRequest, HttpServletResponse)}
* to get a list of feed items.
*/
@Override
protected final void buildFeedEntries(Map<String, Object> model, Channel channel,
HttpServletRequest request, HttpServletResponse response) throws Exception {
List<Item> items = buildFeedItems(model, request, response);
channel.setItems(items);
}
/**
* Subclasses must implement this method to build feed items, given the model.
* <p>Note that the passed-in HTTP response is just supposed to be used for
* setting cookies or other HTTP headers. The built feed itself will automatically
* get written to the response after this method returns.
* @param model the model Map
* @param request in case we need locale etc. Shouldn't look at attributes.
* @param response in case we need to set cookies. Shouldn't write to it.
* @return the feed items to be added to the feed
* @throws Exception any exception that occured during document building
* @see Item
*/
protected abstract List<Item> buildFeedItems(
Map<String, Object> model, HttpServletRequest request, HttpServletResponse response)
throws Exception;
}
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