Guice is the best di library to grasp concepts about inversion of control and dependency injection; other libraries (ie spring) relays heavily on annotations hidding much of the di concepts under cryptic annotations. Guice is mostly declarative and code is self-explanatory Review collected by and hosted on G2.com.

Guice (as the 99% of the di libs) relays on java reflection wich does not cope well with the new reflection-less mainstream Review collected by and hosted on G2.com.