1. Spring AOP Decoded
Mak Bhatamrekar
http://github.com/makrand-bkar
AJCP
http://meetup.com/my-ajcp
Atlanta Java Concept Pros

2. Agenda
• The Problem
• Measuring Performance Project
• AOP At Glance
• PointCut And Advice
• Logging Project
• AOP Configuration
• AOP Proxy & Weaver
• Recap

3. 

4. 

5. Why AOP

6. Measuring Performance
public void convertToFixedDeposit() throws Exception {
//Your Business Logic
Thread.sleep(DEFAULT_SLEEP_INTERVAL);
log.debug("convertToFixedDeposit Complete");
}

7. Measuring Performance
public void convertToFixedDeposit() throws Exception {
StopWatch monitor = new StopWatch();
monitor.start("convertToFixedDeposit");
//Your Business Logic
Thread.sleep(DEFAULT_SLEEP_INTERVAL);
log.debug("convertToFixedDeposit Complete");
monitor.stop();
log.debug(monitor.prettyPrint());
}

8. Challenges
What If it has to be done across 10 classes and 10 methods
•Not DRY Code
•Testing Involved
•Complexity Increases with Number Of Methods
•Code change is permanent
•Invasive
•Time Consuming

9. IS There a Easy Solution

11. AOP Performance Project
Beans.xml
MyMain.java
MyServiceSpringImpl

12. Spring AOP At Glance

13. Spring AOP At Glance
• Pointcut(Expression)
• Advice
• Aspect = PointCut + Advice
• AOP Proxy
• Weaver - Spring AOP or
AspectJ

14. Defining Pointcuts
• execution(<expression>) –Methods Pointcuts
• within() - Class Pointcuts
• Bean() - Bean Pointcuts

15. Execute Expression
execution(“< expression>“); //For Method PointCuts
public String com.mypr.Demo.getName());
public * get*();
* get*()
* get*(*)
* get*(..)
* com.mypr.*.*get*()

16. Within & Bean Expression
within(“< filter>“); //Applies to all the methods of the classes matching filter
within(com.aspects.blog.package.*)
within(com.aspects.blog.package..*)
within(com.aspects.blog.package.DemoClass)
within(DemoClass)
within(DemoInterface+)
within(DemoInterface1+) || within(DemoInterface2+)
bean(*Service)

17. Advice Types
• Before Advice
• After Returning Advice
• After Throwing Advice
• Around Advice

18. Declaring AOP
• AspectJ Annotation Based
– More Flexible, Such as Combined named Pointcuts
– Encapsulation
• Spring XML Based
– Any JDK Version is Good
– Good Choice to configure enterprise services

19. @AspectJ Annotation Style
• @Aspect
• @Pointcut(“execution(* com…abc.Hello(..)”)
• @Before
• @After
• @AfterReturning(pointcut=“”,returning=“retVal”)
• @AfterThrowing
• @Around

20. XML Based Configuration

21. AOP Proxy

22. Weaver
Spring AOP
• No Special Compilation
• Supports Only Method
Pointcuts
• Advise execution on Spring
Beans
AspectJ
• Needs AspectJ Compiler
• Support All Pointcuts
• Advice all domain objects

23. Reference Links
• http://static.springsource.org/spring/docs/2.5.5/refe
rence/aop.html
• http://javabrains.koushik.org/p/spring-
framework.html
• http://www.mkyong.com/spring/

24. Spring AOP Decoded
Mak Bhatamrekar
github :http://github.com/makrand-bkar
twitter : mak-bkar
url : www.careerinjava.com
http://meetup.com/my-ajcp
Atlanta Java Concept Pros