Definition of coarsely grained/finely grained in architecture

Question

Hi,

When talking about APIs, the terms "coarsely grained" or "finely grained" are used a lot. What do these mean/are there any examples?

Thanks

Answer 1

I've seen the distinction used a lot with SOA, e.g.:

http://www.ibm.com/developerworks/webservices/library/ws-soa-granularity/

Basically, coarse-grained systems will have less method calls than a fine-grained system. Clearly coarse-grained methods will be fewer and do more work than the broken-down fine-grained versions.

Coarse grained interfaces will generally be better where calls are expensive, in a distributed system for example.