Spring Beans provides the configuration framework and basic functionality to instantiate, configure, and assemble java objects.

Spring JDBC provides an abstraction layer that simplifies code to use JDBC and the parsing of database-vendor specific error codes.

Spring AOP provides an Alliance-compliant aspect-oriented programming implementation allowing you to define method interceptors and pointcuts to cleanly decouple code that implements functionality that should be separated.

DWR is easy Ajax for Java.