Looping through feed entries with rome

Question

I'm trying to loop through Atom feed entries, and get the title attribute lets say, I found this article, I tried this snipped of code :

for (final Iterator iter = feeds.getEntries.iterator();
     iter.hasNext(); )
{
    element = (Element)iter.next();
    key = element.getAttributeValue("href");
    if ((key != null) &&
        (key.length() > 0))
    {
        marks.put(key, key);
    }

   //Don't have to put anything into map just syso title would be enough
}

But I get exception saying :

java.lang.ClassCastException: com.sun.syndication.feed.synd.SyndEntryImpl cannot be cast to org.jdom.Element at com.emir.altantbh.FeedReader.main(FeedReader.java:47)

What did I do wrong? can anyone direct me towards better tutorial or show me where did I make mistake, I need to loop through entries and extract title tag value. thank you

Imparity

Answer 1

SyndFeed.getEntries() returns a List of SyndEntryImpl. You can not cast from SyndEntryImpl to org.jdom.Element.

You can iterate through all SyndEntry as follows:

for (final Iterator iter = feed.getEntries().iterator();
     iter.hasNext(); )
{
    final SyndEntry entry = (SyndEntry) iter.next();
    String title = entry.getTitle();
    String uri = entry.getUri();
    //...
}

API links

• com.sun.syndication.feed.synd.SyndEntry
• com.sun.syndication.feed.synd.SyndFeed
• java.util.List

---

You can also try this if you're using Java 5.0 and above:

for (SyndEntry entry : (List<SyndEntry>) feed.getEntries()) {
    String title = entry.getTitle();
    String uri = entry.getUri();
    //...
}

There is unchecked cast here, but it should be safe based on the specification of getEntries().

See also

• Java language guide/for-each loop
• Java tutorials/generics

Canica

Great its working, but I have some custom tags inside <entry>, how do I get these? And I have a <content> and inisde that I have a another custom tag, how do I get these? One more thing, which approach is better(which one you recommend) iterator or generics – Imparity

@gandalf: The choice is not iterator vs generics, but rather explicit iterator or implicit one in for-each. For-each, whenever applicable, is always better. – Canica

@gandalf: As to how to get the contents, go to the API links I gave above and look around. Try System.out.println(entry.getContents()); and just experiment. I've never used Rome, all I know about it is what the documentation says. – Canica