Spring AOP

aspects get executed just before related objects run
aspects look like the way triggers work in the database
according to spring configuration files before a method is executed spring configuration file is checked.

aspect oriented programming is different because if there are three objects and these three objects share a common class to use a method you have to extend or make
references as what happens normally in object oriented programming.however in aspect programming you don't need to do these.you create special
classes called aspects and a configuration file.whenever few objects invoke a method before objects are executed aspect configuration file checks on them and then run the aspect class which is also referenced in aspect configuration file

Reference:

http://www.youtube.com/watch?v=QdyLsX0nG30&list=PLE37064DE302862F8&index=1&feature=plpp_video