A lot of programmers I interact with are unable to differentiate between dependency injection and inversion of control. Thanks to the popularity of Spring framework and EJB 3.0 there is now a tendency to use these terms interchangeably, even as they represent distinctly different concepts, resulting in a lot of ambiguities.
Inversion of control has its antecedents in the Hollywood principle (don’t call us, we’ll call you) and is not a design pattern. Rather, it is a general principle that is realized in multiple design patterns. Dependency injection is one such pattern that builds on top of this principle. Inversion of control is one of the tenets for all object-oriented frameworks, but not all object-oriented frameworks provide the features of dependency injection. Read the rest of this entry »
