Spring AOP : Introduction

AOP is termed as Aspect Oriented Programming. Spring AOP is a concept which overcomes the limitations with the simple OOPs concepts. It is a new kind of programming technique which gives the facility to add the functionality dynamically. Here Spring Container is responsible to generating and executing the code dynamically, only we need to configure in the XML or through Annotation. Technically Middle Level Services termed as Aspect and practically we are Aspects to the main business logics at the joinPoints.

For ex- Let suppose if we have a business logic i.e deposit() and we are supposed to apply some middle level services to this business logic at the JoinPoints. 

Now the Question arises is where to apply Advices ?
Basically Advices are applied to three points , they are termed as JoinPoints. So there are Three joinPoints where we can apply Advice( Middle level services).

Comparison of Technical terms of AOP with the practical view

Aspect	Middle Level Services
Advice	Implementation of Middle Level Services
JoinPoints	Where to Apply Advices?

Some of the Spring AOP Terminology we need to know
1. Aspect
2. Advice
3. JoinPoints
4. PointCut
5. Advisor
6. Target
7.  Proxy
8. Weaving.

Business Services -> It is the common services we come across in distributed applications.
Like CustomerServices , AccountServices etc.
It contains the set of Business Logic.

Business Services = set of Business Logics.

Business Logic -> It the main logic which is to be performed and it contains set of business operations.
For Example deposit(), withdraw(), getBalance() are the business logics under some business Services.
Advices are applied to the Business logic.

Business Logic = Set of business Operations

Some of the Advice/ Middle Level Services that we are attaching with the Aspects ( Business Logic ) are
Security Service , Transaction Service , log Service etc.

Spring provides three way to implement the Spring AOP :
1. Using Spring API based AOP ( 1.0 )
2. Using Spring Annotation based AOP ( 2.0 ) - > Recommended to use
3. Using XML schema based AOP ( 2.0 )