From: MikkelFJ <mikkelfj-anti-spam@...>
Date: 2003-02-14T05:30:12+09:00
Subject: Re: FreeBase/Databus design of FreeRIDE


<coma_killen@fastmail.fm> wrote in message
news:20030213144209.575F04840E@server2.fastmail.fm...
> Hi,
> So if there are any FreeRIDE developers (or others) out there
> please answer:

I'm not a FreeRIDE developer, but let me give it a shot.

> * Why did you chose to base FreeRIDE on the DataBus design?

It was considered to write an Eclipse plugin for Ruby. Instead FreeRide was
design completely in Ruby.
Eclipse has an extensive plug-in mechanism based an a software databus.
Apparently, the databus design goes even further back in time in various
java implementations.

> * What are its main benefits?

Decoupling is a powerful design strategy. Decoupling happens in message
based systems and also in OO based systems using information hiding. Pure
message based systems tend to lack some structure while pure OO
implementations tend to give a rather tight coupling design-wise. Also, OO
frameworks tend to be compile time dependent - this is not as strong a point
in Ruby - but there are still constraints.
A software databus makes it very easy to decouple systems such that they
communicate on a need to know basis. Contrary to simple message based
systems there is an infrastructure to organise message exhange and
discovery.

> * What are its main drawbacks?

It is rather expensive to design and implement.

> * Any links to info on related designs/principles?

Hmm - a far shot - but take a look at the QNX message passing operating
system and the namespace it uses to organise communicating processes on same
node or cross network.

Mikkel