rss10feed.java

wiki建站资源 java编写的 很好用

/*
 * (C) Janne Jalkanen 2005
 * 
 */
package com.ecyrd.jspwiki.rss;

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Iterator;

import org.apache.ecs.xml.XML;

import com.ecyrd.jspwiki.WikiContext;
import com.ecyrd.jspwiki.WikiEngine;
import com.ecyrd.jspwiki.WikiPage;

/**
 *  @author jalkanen
 *
 *  @since 
 */
public class RSS10Feed extends Feed
{
    public RSS10Feed( WikiContext context )
    {
        super(context);
    }
    
    private XML getRDFItems()
    {
        XML items = new XML( "items" );
        
        XML rdfseq = new XML( "rdf:Seq" );
        
        for( Iterator i = m_entries.iterator(); i.hasNext(); )
        {
            Entry e = (Entry)i.next();

            String url = e.getURL();

            rdfseq.addElement( new XML("rdf:li").addAttribute( "rdf:resource", url ) );
        }
        
        items.addElement( rdfseq );
        
        return items;
    }
    
    private void addItemList( XML root )
    {
        SimpleDateFormat iso8601fmt = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'");
        
        WikiEngine engine = m_wikiContext.getEngine();
        
        for( Iterator i = m_entries.iterator(); i.hasNext(); )
        {
            Entry e = (Entry)i.next();
            
            String url = e.getURL();
            
            XML item = new XML( "item" );
            item.addAttribute( "rdf:about", url );
            
            item.addElement( new XML("title").addElement( format(e.getTitle()) ) );

            item.addElement( new XML("link").addElement( url ) );

            XML content = new XML("description");
            
            // TODO: Add a size limiter here
            content.addElement( format(e.getContent()) );

            item.addElement( content );

            WikiPage p = e.getPage();
            
            if( p.getVersion() != -1 )
            {
                item.addElement( new XML("wiki:version").addElement( Integer.toString(p.getVersion()) ) );
            }

            if( p.getVersion() > 1 )
            {
                item.addElement( new XML("wiki:diff").addElement( engine.getURL( WikiContext.DIFF,
                                                                                 p.getName(),
                                                                                 "r1=-1",
                                                                                 true) ) );
            }

           
            //
            //  Modification date.
            //
            Calendar cal = Calendar.getInstance();
            cal.setTime( p.getLastModified() );
            cal.add( Calendar.MILLISECOND, 
                     - (cal.get( Calendar.ZONE_OFFSET ) + 
                        (cal.getTimeZone().inDaylightTime( p.getLastModified() ) ? cal.get( Calendar.DST_OFFSET ) : 0 )) );

            item.addElement( new XML("dc:date").addElement( iso8601fmt.format( cal.getTime() )));
           
            //
            //  Author
            String author = e.getAuthor();
            if( author == null ) author = "unknown";

            XML contributor = new XML("dc:creator");
            
            item.addElement( contributor );
            
            XML description = new XML("rdf:Description");
            if( m_wikiContext.getEngine().pageExists(author) )
            {
                description.addAttribute( "link", engine.getURL( WikiContext.VIEW, 
                                                                 author,
                                                                 null,
                                                                 true ) );
            }
            
            description.addElement( new XML("value").addElement( format(author) ) );
            contributor.addElement( description );
           
            //  PageHistory

            item.addElement( new XML("wiki:history").addElement( engine.getURL( WikiContext.INFO,
                                                                                p.getName(),
                                                                                null,
                                                                                true ) ) );
            
            //
            //  Add to root
            //
            
            root.addElement( item );
        }
    }
    
    private XML getChannelElement()
    {
        XML channel = new XML( "channel" );

        channel.addAttribute("rdf:about", m_feedURL );
        
        channel.addElement( new XML("link").addElement( m_feedURL ) );
        
        if( m_channelTitle != null )
            channel.addElement( new XML("title").addElement( format(m_channelTitle)) );
        
        if( m_channelDescription != null )
            channel.addElement( new XML("description").addElement( format(m_channelDescription)) );
        
        if( m_channelLanguage != null )
            channel.addElement( new XML("dc:language").addElement(m_channelLanguage) );

        channel.setPrettyPrint( true );
        
        channel.addElement( getRDFItems() );
        
        return channel;
    }
    
    /* (non-Javadoc)
     * @see com.ecyrd.jspwiki.rss.Feed#getString()
     */
    public String getString()
    {
        XML root = new XML("rdf:RDF");
        
        root.addAttribute( "xmlns:rdf", "http://www.w3.org/1999/02/22-rdf-syntax-ns#" );
        root.addAttribute( "xmlns", "http://purl.org/rss/1.0/" );
        root.addAttribute( "xmlns:dc", "http://purl.org/dc/elements/1.1/" );
        root.addAttribute( "xmlns:wiki", "http://purl.org/rss/1.0/modules/wiki/" );
        
        root.addElement( getChannelElement() );
        
        addItemList( root );
        
        root.setPrettyPrint( true );
                
        return root.toString();
    }

}