Ralph Schindler has written up a new post for his blog today looking at APIs and some things to consider when building them. These aren't the web service APIs you're thinking of - this is the interfaces your code uses to talk to it's own parts.

It's important to have a common understanding of the actual problem area. When we talk about names, we are really talking about the API. An API is a particular set of rules and specifications that a developer can follow to access and make use of the services and resources provided by another particular software program, component or library. Put another way, it is an interface between various software pieces and facilitates their interaction, similar to the way the user interface facilitates interaction between humans and computers.

He talks about the two different APIs you're usually building at the same time - a consumption API that is the method others use to consume it and the extension API, how the feature allows others to improve upon it. He shares his own API philosophy and a three tips he's learned along the way to make his APIs more robust:

• Adopt A Common Namespace & Class Naming Scheme
• Avoid Doing Too Much In the Constructor
• Avoid final And private