Obviously we are not even close to the Star Trek vision of software development (See my previous Blog). To get to the Star Trek model we first must have well defined component models and component communication paths. There is a lot of talk about component developement and the reuse of components. It has been my experence that while we all see components as an extremely desirable goal, developement teams rarely start the development process by discovering the needed components. Instead developers rush head long into discovering the structural aspect of the design (AKA the class structure), and after the applications structure has been designed developers hope that components will fall out of the design.

If you wait until after the application has been designed or worse after the application has been written, you usally end up with components that are not truely black boxes. You find that Compnent A has hard dependencies to Component B. The problem with hard dependencies is that it makes application very ridge, and hard to extend. Enter SOA stage right. SOA and Web Services are two very hot topics. Why? Both SOA and Web Services help developers break hard dependencies between software components.

When you first discover the components needed by an appliation, you tend to discover the communication requirements needed to allow components interact. Once you have the communication requirements detailed it is easy to write interface to break the dependencies between components. Once you have the interfaces define it is easy to write new components to plug into existing components and extend existing applicatons.