The Spring EL is similar with OGNL and JSF EL, and evaluated or executed
during the bean creation time. In addition, all Spring expressions are
available via XML or annotation.

In this tutorial, we show you how to use Spring Expression Language(SpEL)
, to inject String, integer and bean into property, both in XML and
annotation.

http://www.mkyong.com/spring3/spring-el-hello-world-example/