It is now possible to configure Spring's dependency injection with annotations. This means that annotations can be used in Spring to mark fields, methods and classes that need dependency injection. Spring also supports auto-wiring of the bean dependencies, that is, resolving the collaborating beans by inspecting the contents of the BeanFactory. Now there are annotations that can be used to indicate fields that are to be auto-wired. Furthermore, auto-detection of annotated components in the classpath is also supported now. When these capabilities are combined, the amount of configuration and dependency mapping in the Spring configuration files is reduced drastically.
According to the Spring development team, the core theme of Spring 2.5 that was released in October 2007 is to provide comprehensive support for configuration annotations in application components. Annotation support was first announced in Spring 2.0, and has been significantly enhanced in Spring 2.5. It introduces support for a complete set of configuration annotations.