Spring 3 MVC And RSS Feed Example

In Spring 3, comes with a abstract class “AbstractRssFeedView” to generate RSS feed view, using java.net’s ROME package. In this tutorial, we show you how to generate a RSS feed view from Spring MVC framework.

Technologies used :

1. Spring 3.0.5.RELEASE
2. ROME 1.0.0
3. JDK 1.6
4. Eclipse 3.6
5. Maven 3

At the end of the tutorial, when you visit this URL – http://localhost:8080/SpringMVC/rest/rssfeed, browser will return following RSS feed content :

<? xml version="1.0" encoding="UTF-8" ?>
< rss  xmlns:content ="http://purl.org/rss/1.0/modules/content/"  version ="2.0" >
   < channel >
     < title >Mkyong Dot Com </ title >
     < link >http://www.mkyong.com </ link >
     < description >Java Tutorials and Examples </ description >
     < item >
       < title >Spring MVC Tutorial 1 </ title >
       < link >http://www.mkyong.com/spring-mvc/tutorial-1 </ link >
       < content:encoded >Tutorial 1 summary ... </ content:encoded >
       < pubDate >Tue, 26 Jul 2011 02:26:08 GMT </ pubDate >
     </ item >
     < item >
       < title >Spring MVC Tutorial 2 </ title >
       < link >http://www.mkyong.com/spring-mvc/tutorial-2 </ link >
       < content:encoded >Tutorial 2 summary ... </ content:encoded >
       < pubDate >Tue, 26 Jul 2011 02:26:08 GMT </ pubDate >
     </ item >
   </ channel >

</rss> 

1. Directory Structure

Review the final project structure.

 

2. Project Dependencies

For Maven, declares following dependencies in your pom.xml.

< properties >
         < spring.version >3.0.5.RELEASE </ spring.version >
     </ properties >
 
     < dependencies >
 
         <!--  Spring 3 dependencies  -->
         < dependency >
             < groupId >org.springframework </ groupId >
             < artifactId >spring-core </ artifactId >
             < version >${spring.version} </ version >
         </ dependency >
 
         < dependency >
             < groupId >org.springframework </ groupId >
             < artifactId >spring-web </ artifactId >
             < version >${spring.version} </ version >
         </ dependency >
 
         < dependency >
             < groupId >org.springframework </ groupId >
             < artifactId >spring-webmvc </ artifactId >
             < version >${spring.version} </ version >
         </ dependency >
 
         <!--  RSS  -->
         < dependency >
             < groupId >net.java.dev.rome </ groupId >
             < artifactId >rome </ artifactId >
             < version >1.0.0 </ version >
         </ dependency >
 
         <!--  for compile only, your container should have this  -->
         < dependency >
             < groupId >javax.servlet </ groupId >
             < artifactId >servlet-api </ artifactId >
             < version >2.5 </ version >
             < scope >provided </ scope >
         </ dependency >
 

    </dependencies> 

3. Model

A simple POJO, later use this object to generate the RSS feed content.

package com.mkyong.common.model;
 
import java.util.Date;
 
public  class SampleContent {
 
    String title;
    String url;
    String summary;
    Date createdDate;
 
     // getter and seeter methods

} 

4. AbstractRssFeedView

Create a class extends AbstractRssFeedView, and override the buildFeedMetadata and buildFeedItems methods, below code should be self-explanatory.

package com.mkyong.common.rss;
 
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.servlet.view.feed.AbstractRssFeedView;
import com.mkyong.common.model.SampleContent;
import com.sun.syndication.feed.rss.Channel;
import com.sun.syndication.feed.rss.Content;
import com.sun.syndication.feed.rss.Item;
 
public  class CustomRssViewer  extends AbstractRssFeedView {
 
    @Override
     protected  void buildFeedMetadata(Map<String, Object> model, Channel feed,
        HttpServletRequest request) {
 
        feed.setTitle("Mkyong Dot Com");
        feed.setDescription("Java Tutorials and Examples");
        feed.setLink("http://www.mkyong.com");
 
         super.buildFeedMetadata(model, feed, request);
    }
 
 
    @Override
     protected List<Item> buildFeedItems(Map<String, Object> model,
        HttpServletRequest request, HttpServletResponse response)
         throws Exception {
 
        @SuppressWarnings("unchecked")
        List<SampleContent> listContent = (List<SampleContent>) model.get("feedContent");
        List<Item> items =  new ArrayList<Item>(listContent.size());
 
         for(SampleContent tempContent : listContent ){
 
            Item item =  new Item();
 
            Content content =  new Content();
            content.setValue(tempContent.getSummary());
            item.setContent(content);
 
            item.setTitle(tempContent.getTitle());
            item.setLink(tempContent.getUrl());
            item.setPubDate(tempContent.getCreatedDate());
 
            items.add(item);
        }
 
         return items;
    }
 

} 

6. Spring Bean Registration

In a Spring bean definition file, enable the auto component scanning, and register your “CustomRssViewer” class and “BeanNameViewResolver” view resolver, so that when view name “rssViewer” is returned, Spring know it should map to bean id “rssViewer“.

File : mvc-dispatcher-servlet.xml

< beans  xmlns ="http://www.springframework.org/schema/beans"
    xmlns:context ="http://www.springframework.org/schema/context"
    xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation ="
        http://www.springframework.org/schema/beans     
        http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
        http://www.springframework.org/schema/context 
        http://www.springframework.org/schema/context/spring-context-3.0.xsd" >
 
     < context:component-scan  base-package ="com.mkyong.common.controller"   />
 
     <!--  Map returned view name "rssViewer" to bean id "rssViewer"  -->
     < bean  class ="org.springframework.web.servlet.view.BeanNameViewResolver"   />
 
     < bean  id ="rssViewer"  class ="com.mkyong.common.rss.CustomRssViewer"   />
 

</beans> 

Note

File content of web.xml is omitted, just a standard configuration, if you are interest, download this whole project at the end of the article.

7. Demo

URL : http://localhost:8080/SpringMVC/rest/rssfeed

How about Atom?
For Atom, you just need to extends  AbstractAtomFeedView, instead of  AbstractRssFeedView.

Download Source Code

Download it – SpringMVC-RSS-Feed-Example.zip (9 KB)