RE: DDS Screens To Java

["Joe Pluta" <joepluta@xxxxxxxxxxxxxxxxx>]

> From: Dan Bale
>
> Umm, please explain "Swing interface" and "thick client"  (I know
> Windoze is
> "thick", as in "thick in the skull", is this the "thick" you're
> speaking of?
> <g>)

The term "thick client" has changed over the years, but my own personal
distinction is as follows:

1. Thin client applications use commonly available software that is freely
available.  This pretty much limits the playing field to 5250 and browser
clients, since you can get a free interface for either one.

2. Thick clients require proprietary software to be loaded on the client.
This might be a vendor's middleware, or actual applications.  This includes
Visual Basic front ends or proprietary screen scrapers.

The primary differences from a business standpoint are operational.  Thin
clients require little or no work on the part of the IS staff to keep up
with changing application requirements.  The client is usually platform
independent.  Most Windows machines come with Internet Explorer, and most
other boxes have Netscape or Opera or some equivalent.  On the other hand,
with a thick client, every time there is a change to the application, you
have to install a new piece of software on the client, and that software is
often platform-specific.

The primary difference from a user standpoint is interface - thick clients
provide a more robust, graphical interface than browsers or 5250 emulators.
Two typical interfaces are the "standard" Windows interface as epitomized by
Visual Basic and the Java thick client interface known as Swing.  Swing is a
bit less powerful and quite a bit slower than the VB interface, but has the
advantage of being platform independent.

There is no clear distinction - some browser-based applications require
specific versions of browsers, while you could conceivably have a
sophisticated mechanism for automatically downloading and installing new
version of thick client software, thereby blurring the distinction.  And as
I pointed out, Java thick clients run anywhere, so coupled with a reliable
means of downloading changes, Java thick clients could run anywhere.

Each of these options has its place.  Personally, I spent several years
creating a highly sophisticated thick client interface using OS/2 and
OS/400, only to find that the implementation hurdles were every bit as
difficult to overcome as the design and implementation of the product.
Currently, I provide an HTML interface that requires absolutely no PC
software, either for development or deployment, and I'm finding that the
management issue is almost complete removed.

Joe