(Spring is an open source IoC Inversion of Control and AOP container structure. Its primary intent is to simplify enterprise development. The so-called control rotation means that the use itself does not serve as the creation and protection of dependent targets. The creation and protection of dependent targets are performed by external containers. In this way, the control right is transferred from the use to the external container, and the transfer of control right is rotation. Dependency injection refers to dynamically injecting dependency targets into components by external containers during runtime.
Spring2.5 Learning Notes.pdf)