CS 4448 - Fall 1998
Object-Oriented Programming and Design
Talk 4.1
by
Jason Nix

Net programming is a tangled Web; components offer easy interactivity,
but standards aren't yet set.

by

Dave Kosiur

• Introduction
  Internet application developers are looking for ways to use reusable components/objects that fit into a "container", most common being the web browser.To accomplish this, two decisions need to be made.
  • What type of component to use.
    The two types of components that this paper discuss are Java Applets and Microsoft's ActiveX Components.
  • How to distribute the component over the internet.
    Sun chose to go with the CORBA (Common Object Request Broker) model, whereas Microsoft went with the DCOMM (Distrubuted Component Object Model) model.


• History
  Originally, when Netscape decided to try to increase the functionality of their browser, they used plug-ins. Plug-ins did give added interactivity but they had a couple of problems. First, they are very machine dependant creating the neccessity for everyone to download a specific plug-in for their specific hardwar. Second, they only communicate with the browser. For these reasons, Java and ActiveX have superceded plub-ins for increasing browser capabilities.


• ActiveX Components
  Advantages -
  • ActiveX components are based on Microsoft's OLE (Object Linking and embedding) components. This gives the functionality that once and ActiveX component has been downloaded to your browser, it can be directly opened and manipulated by any application that supports that type of OLE component.
  • ActiveX components are much faster to open and manipulate that Java Applets.
  Disadvantages -
  • ActiveX components still have the problem of platform dependance so must be compiled for each spacific archetecture.
  • ActiveX components currently only work with the Microsoft Internet Explorer, which limits their use to only Windows platforms


• Java Applets
  Advantages -
  
  • Java is platform independant.
  • Java is supported by Netasape and by Microsoft Internet Explorer. This makes Java Applets available to nearly every platform.
  Disadvantages -
  
  • Running Java applets is currently very slow.


• DCOM vs. CORBA
  DCOM is fairly new. CORBA has a longer development history and stronger record with implementation. Groups like the Object Management Group are working on developing a standard for linking DCOM and CORBA which whill bring this battle closer.