SingleBookFeedProducer.java

package com.wooki.services.feeds.impl;

import java.util.ArrayList;
import java.util.List;

import org.apache.tapestry5.ioc.annotations.Inject;

import com.sun.syndication.feed.atom.Feed;
import com.sun.syndication.feed.atom.Link;
import com.wooki.domain.biz.BookManager;
import com.wooki.domain.model.Book;
import com.wooki.services.EnumServiceLocator;
import com.wooki.services.activity.ActivitySourceType;

/**
 * Produces the feed for a single book.
 * 
 * @author ccordenier
 */
public class SingleBookFeedProducer extends AbstractFeedProducer
{

    @Inject
    private EnumServiceLocator locator;

    @Inject
    private BookManager bookManager;

    /**
     * Read book definition and generate corresponding feed.
     */
    public Feed produce(Long... context)
    {

        if (context == null || !(context.length > 0)) { throw new IllegalArgumentException(
                "SingleBookFeedProducer requires the book id as a parameter"); }

        Long bookId = context[0];
        Book book = this.bookManager.findById(bookId);

        String title = this.messages.getMessages().format("recent-activity", book.getTitle());
        String id = book.getSlugTitle();

        List<Link> alternateLinks = new ArrayList<Link>();

        Link linkToSelf = new Link();
        linkToSelf.setHref(lnkSource.createPageRenderLink("book/index", false, book.getId())
                .toURI());
        linkToSelf.setTitle(book.getTitle());

        alternateLinks.add(linkToSelf);

        return super.fillFeed(id, title, alternateLinks, locator
                .getService(ActivitySourceType.BOOK).listActivitiesForFeed(bookId));
    }

}