Basic Design Concept:

• The Framework knows about the types of objects – SearchSources, SearchForms, ResultRenderers etc. and the basic roles and relationships of these objects.

  It doesn’t know (and doesn’t need to know) anything else.

• Each object is in control of its own internal XML configuration structure.
  
• This allows new objects to be added and plugged in without any changes to the framework itself.

• Object relationships are determined at deployment or at run time - not at compile time.
  
• Flexible object composition - object design defines containment patterns of interface classes - enables customized applications to be built with reusable parts.
  
• Composite implementations of standard interfaces enable logging, filtering, formatting operations etc. to be inserted where needed.
  
• Embedded search operations provide dynamic data integration.
  

• Presentation layer consists of JSP pages, custom tags and XML configurable "renderers" - cleaner separation of pure presentation and application elements even for complex interaction patterns such as AJAX.
  
• Rendering objects have access to back-end resources and session context provide for greater flexibility.
  
• HTML generation by Java classes - heresy? No:
  • Enables code reuse through inheritance, composition, instantiation.
  • Permits the use of object Design patterns in UI development.
  • Minimizes JSP - object coupling: simplifies code maintenance.
  • Elminates The HTML-Java-HTML-Java (ad nauseum) "Lasagna Pattern".
    
• Web applications require code that runs on both client and server. Module encapsulation ensures that client-side javascript is coordinated and maintained in synchrony with server-side logic.