How Struts frame work will develop integration logic automatically?

There is nothing like integration... what previously the manual programmers would take into consideration like security, services, pooling etc., etc., all this are provided as a package... to make the life of developer easier. I remember while developing an application 5 years back, we used to write seperate modules to handle issues relating to security, connection pooling, exception traversing, etc., etc. With Struts all these are available as in-built features.. thus reducing the nuances of olden days of programming.