[Tapestry-developer] Dynamically Loading Pages (Round II)

[Dorothy Gantenbein]

Howard -   Thanks for all your input and patience.   Here is another shot at this problem.  Whenever a page is requested that is not defined by the application file, then I want to dynamically load the specification of the page.  To do this, I decorated the PageSource.  For my engine class, I added the following method...   public class StudyServerEngine extends SimpleEngine {    ...      protected IPageSource createPageSource()    {       return new DynamicPageSource(getResourceResolver());    }      ... }   My DynamicPageSource decorates the page source.  Basically, its job is to intercept getPage requests and dynamically load the page when it is needed.   public class DynamicPageSource implements IPageSource, IRenderDescription {    public DynamicPageSource(IResourceResolver resolver)    {       super();       _delegate = new PageSource(resolver);    }      public IPage getPage(IEngine engine, String pageName, IMonitor monitor)       throws PageLoaderException    {       // check if page exists before trying to instantiate page       ApplicationSpecification applicationSpec = engine.getSpecification();       PageSpecification spec = applicationSpec.getPageSpecification(pageName);       if (spec == null) {          _log.debug("Page not found="+pageName);          spec = _parser.getFactory().createPageSpecification(pageName);          _log.debug("   found spec="+spec);          applicationSpec.setPageSpecification(pageName, spec);       }         // instantiate the page       IPage page = _delegate.getPage(engine, pageName, monitor);       return page;    }      public void releasePage(IPage page)    {       _delegate.releasePage(page);    }      public void reset()    {       _delegate.reset();    }      public IBinding getFieldBinding(String fieldName)    {       return _delegate.getFieldBinding(fieldName);    }      public IBinding getStaticBinding(String value)    {       return _delegate.getStaticBinding(value);    }      public IAsset getExternalAsset(String URL)    {       return _delegate.getExternalAsset(URL);    }      public IAsset getContextAsset(String assetPath)    {       return _delegate.getContextAsset(assetPath);    }      public IAsset getPrivateAsset(String resourcePath)    {       return _delegate.getPrivateAsset(resourcePath);    }       public void renderDescription(IResponseWriter writer)    {       _delegate.renderDescription(writer);    }       // private stuff    private static final SpecificationParser _parser = new SpecificationParser();    private static final Logger _log = Logger.getLogger(DynamicPageSource.class);      private PageSource _delegate; }   What I am still trying to figure out is how to integrate the DefaultSpecificationSource decoration.   Thanks... Dorothy