filtermanager.java

jspwiki source code,jspwiki source code

        Document doc = new SAXBuilder().build( xmlStream );
        
        XPath xpath = XPath.newInstance("/pagefilters/filter");
    
        List nodes = xpath.selectNodes( doc );
        
        for( Iterator i = nodes.iterator(); i.hasNext(); )
        {
            Element f = (Element) i.next();
            
            String filterClass = f.getChildText("class");

            Properties props = new Properties();
            
            List params = f.getChildren("param");
            
            for( Iterator par = params.iterator(); par.hasNext(); )
            {
                Element p = (Element) par.next();
                
                props.setProperty( p.getChildText("name"), p.getChildText("value") );
            }

            initPageFilter( filterClass, props );
        }
        
    }
    
 
    /**
     *  Does the filtering before a translation.
     *  
     *  @param context The WikiContext
     *  @param pageData WikiMarkup data to be passed through the preTranslate chain.
     *  @throws FilterException If any of the filters throws a FilterException
     *  @return The modified WikiMarkup
     *  
     *  @see PageFilter#preTranslate(WikiContext, String)
     */
    public String doPreTranslateFiltering( WikiContext context, String pageData )
        throws FilterException
    {
        fireEvent( WikiPageEvent.PRE_TRANSLATE_BEGIN, context );

        for( Iterator i = m_pageFilters.iterator(); i.hasNext(); )
        {
            PageFilter f = (PageFilter) i.next();

            pageData = f.preTranslate( context, pageData );
        }

        fireEvent( WikiPageEvent.PRE_TRANSLATE_END, context );

        return pageData;
    }

    /**
     *  Does the filtering after HTML translation.
     *  
     *  @param context The WikiContext
     *  @param htmlData HTML data to be passed through the postTranslate
     *  @throws FilterException If any of the filters throws a FilterException
     *  @return The modified HTML
     *  @see PageFilter#postTranslate(WikiContext, String)
     */
    public String doPostTranslateFiltering( WikiContext context, String htmlData )
        throws FilterException
    {
        fireEvent( WikiPageEvent.POST_TRANSLATE_BEGIN, context );

        for( Iterator i = m_pageFilters.iterator(); i.hasNext(); )
        {
            PageFilter f = (PageFilter) i.next();

            htmlData = f.postTranslate( context, htmlData );
        }

        fireEvent( WikiPageEvent.POST_TRANSLATE_END, context );

        return htmlData;
    }

    /**
     *  Does the filtering before a save to the page repository.
     *  
     *  @param context The WikiContext
     *  @param pageData WikiMarkup data to be passed through the preSave chain.
     *  @throws FilterException If any of the filters throws a FilterException
     *  @return The modified WikiMarkup
     *  @see PageFilter#preSave(WikiContext, String)
     */
    public String doPreSaveFiltering( WikiContext context, String pageData )
        throws FilterException
    {
        fireEvent( WikiPageEvent.PRE_SAVE_BEGIN, context );

        for( Iterator i = m_pageFilters.iterator(); i.hasNext(); )
        {
            PageFilter f = (PageFilter) i.next();

            pageData = f.preSave( context, pageData );
        }

        fireEvent( WikiPageEvent.PRE_SAVE_END, context );

        return pageData;
    }

    /**
     *  Does the page filtering after the page has been saved.
     * 
     *  @param context The WikiContext
     *  @param pageData WikiMarkup data to be passed through the postSave chain.
     *  @throws FilterException If any of the filters throws a FilterException
     * 
     *  @see PageFilter#postSave(WikiContext, String)
     */
    public void doPostSaveFiltering( WikiContext context, String pageData )
        throws FilterException
    {
        fireEvent( WikiPageEvent.POST_SAVE_BEGIN, context );

        for( Iterator i = m_pageFilters.iterator(); i.hasNext(); )
        {
            PageFilter f = (PageFilter) i.next();

            // log.info("POSTSAVE: "+f.toString() );
            f.postSave( context, pageData );
        }

        fireEvent( WikiPageEvent.POST_SAVE_END, context );
    }

    /**
     *  Returns the list of filters currently installed.  Note that this is not
     *  a copy, but the actual list.  So be careful with it.
     *  
     *  @return A List of PageFilter objects
     */
    public List getFilterList()
    {
        return m_pageFilters;
    }

    /**
     * 
     * Notifies PageFilters to clean up their ressources.
     *
     */
    public void destroy()
    {
        for( Iterator i = m_pageFilters.iterator(); i.hasNext(); )
        {
            PageFilter f = (PageFilter) i.next();

            f.destroy( m_engine );
        }        
    }
    
    // events processing .......................................................

    /**
     *  Fires a WikiPageEvent of the provided type and WikiContext.
     *  Invalid WikiPageEvent types are ignored.
     *
     * @see com.ecyrd.jspwiki.event.WikiPageEvent 
     * @param type      the WikiPageEvent type to be fired.
     * @param context   the WikiContext of the event.
     */
    public final void fireEvent( int type, WikiContext context )
    {
        if ( WikiEventManager.isListening(this) && WikiPageEvent.isValidType(type) )
        {
            WikiEventManager.fireEvent(this,
                    new WikiPageEvent(m_engine,type,context.getPage().getName()) );
        }
    }

    /**
     *  {@inheritDoc}
     */
    @SuppressWarnings("unchecked")
    public Collection modules()
    {
        ArrayList modules = new ArrayList();
        
        modules.addAll( m_pageFilters );
        
        return modules;
    }

    private void registerFilters()
    {
        log.info( "Registering filters" );

        SAXBuilder builder = new SAXBuilder();

        try
        {
            //
            // Register all filters which have created a resource containing its properties.
            //
            // Get all resources of all plugins.
            //

            Enumeration resources = getClass().getClassLoader().getResources( PLUGIN_RESOURCE_LOCATION );

            while( resources.hasMoreElements() )
            {
                URL resource = (URL) resources.nextElement();

                try
                {
                    log.debug( "Processing XML: " + resource );

                    Document doc = builder.build( resource );

                    List plugins = XPath.selectNodes( doc, "/modules/filter");

                    for( Iterator i = plugins.iterator(); i.hasNext(); )
                    {
                        Element pluginEl = (Element) i.next();

                        String className = pluginEl.getAttributeValue("class");

                        PageFilterInfo pluginInfo = PageFilterInfo.newInstance( className, pluginEl );

                        if( pluginInfo != null )
                        {
                            registerPlugin( pluginInfo );
                        }
                    }
                }
                catch( java.io.IOException e )
                {
                    log.error( "Couldn't load " + PLUGIN_RESOURCE_LOCATION + " resources: " + resource, e );
                }
                catch( JDOMException e )
                {
                    log.error( "Error parsing XML for filter: "+PLUGIN_RESOURCE_LOCATION );
                }
            }
        }
        catch( java.io.IOException e )
        {
            log.error( "Couldn't load all " + PLUGIN_RESOURCE_LOCATION + " resources", e );
        }
    }

    private void registerPlugin(PageFilterInfo pluginInfo)
    {
        m_filterClassMap.put( pluginInfo.getName(), pluginInfo );
    }

    /**
     *  Stores information about the filters.
     * 
     *  @since 2.6.1
     */
    private static final class PageFilterInfo extends WikiModuleInfo
    {
        private PageFilterInfo( String name )
        {
            super(name);
        }
        
        protected static PageFilterInfo newInstance(String className, Element pluginEl)
        {
            if( className == null || className.length() == 0 ) return null;
            PageFilterInfo info = new PageFilterInfo( className );

            info.initializeFromXML( pluginEl );
            return info;        
        }
    }
}