Playing with Spring AOP

###Goal Inject repository to the entity using AOP.

###Why? Trying to follow DDD, I want to test a way to avoid anemic models, leading in self-explanatory use cases.

###Found problems

• First steps with Spring AOP are easy...

  but, now that I understand how AOP is working with Spring I think that I can't use Spring AOP for intercept method calls on non beans classes.

  Spring AOP works creating Proxys for classes that are registered in the Dependency Injection Container.

• Dealing with java agents could be problematic to lauch tests, launch from IDE...

• First attempt to use the LTW was not working... Examples and documentation found was not very good.

###Run

# Finally both agents are needed, found example in (https://github.com/jwilsoncredera/spring-aop-blog)
./gradlew build && java -javaagent:libs/aspectjweaver-1.8.10.jar -javaagent:libs/spring-instrument-4.3.6.RELEASE.jar -jar build/libs/ddd-aop-entity-behaviour-1.0-SNAPSHOT.jar

# Or use the sh with that calls
./run.sh

###Test

# manually with curl
curl -XPUT --header "Content-Type: application/json" localhost:8080/users/1/followers/2 -v

# Then STDOUT should print some messages telling what is going on...

Good feelings

IntelliJ has a good support for aspects, and the String syntax in the annotation is highlighted, navigable...

Spring AOP is really fast, but when the aspectj agent is working bootstrap is 3 times slower...

Current status

It's working!

• Use case
• Aspect declaration
• Entity without repository