A brief introduction to Spring framework
Spring is a lightweight and open source enterprise framework created way back in 2003. Modularity is the heart of Spring framework. Because of this, Spring can be used from the presentation layer to the persistence layer.
The good thing is, Spring doesn't force you to use Spring in all layers. For example, if you use Spring in the persistence layer, you are free to use any other framework in presentation of the controller layer.
Another good part of Spring is its Plain Old Java Object (POJO) model-based framework. Unlike other frameworks, Spring doesn't force your class to extend or implement any base class or interface of Spring API; however, Spring does provide a set of classes to use other frameworks, such as ORM frameworks, logging framework, Quartz timers, and other third-party libraries, which will help you to integrate those frameworks with Spring.
More on this: Spring allows you to change the similar framework without changing the code. For example...