 Is a programming paradigm  Extends OOP  Enables modularization of cross cutting concerns

Dependency Injection  Target code depends on the behavior to be applied AOP  Applying a common behavior to large number of elements of code. Raise your hand if you want a Pizza ! Monday 9 AM

 Interception  Introduction  Inspection  Modularization / Encapsulation Open classes – extend classes Reflection – query meta data YES

Meta Programming  Program as Data  Read, generate, modify, analyze or transform other programs (itself)  Code modified at run time  Can we use it to do AOP?  Is it effective? AOP  Uses meta programming as a Vehicle.  Uses the meta programming concepts  Frameworks :-  Aquarium  AspectR

 Aspect  Advice  Pointcut  Join Point  Weaver

 Pointcut  execution – applied to methods  Within – applied to class level  Args – applied based on the parameters to methods  Advice

 Any public method  execution(public * * (..))  any method with a name beginning with “get“  execution(* get*(..))  Any method with a name beginging with “set” and has more than one parameter  execution(* set*(*))  Any method defined in the appropriate package  execution(* edu.diging.controller.*.*(..))

@Aspect public class EmployeeAspectPointcut public void transactionAdvice(JointPoint jointPoint){ System.out.println("Executing firstAdvice on ="+joinPoint.toString()); System.out.println("Agruments Passed=" + Arrays.toString(joinPoint.getArgs())); public void customAdvice(){ System.out.println("Executing secondAdvice on getName()"); String getName(*))") public void getNamePointcut(){} }

A standardized AOP framework has never really taken off in Ruby because the language itself already supports most of the desirable functionality of AOP. David Heinemeier Hansson of Rails fame

 Aquarium can run on Jruby  Ruby Aspects can advise Java  Java aspects can advise Ruby

 Promotes separation of concerns  Code reuse and modularization  Loose coupling

Thank you