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@AspectJ pointcut for all methods of a class with specific annotation

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How do you specify a single pointcut for multiple packages?

You can use boolean operators: expression="execution(* package1. *. *(..))

What is pointcut annotation?

Pointcut is a set of one or more JoinPoint where an advice should be executed. You can specify Pointcuts using expressions or patterns as we will see in our AOP examples. In Spring, Pointcut helps to use specific JoinPoints to apply the advice.

What is pointcut in AspectJ?

AspectJ provides primitive pointcuts that capture join points at these times. These pointcuts use the dynamic types of their objects to pick out join points. They may also be used to expose the objects used for discrimination. this(Type or Id) target(Type or Id)

What methods does this pointcut expression reference?

This pointcut matches any method that starts with find and has only one parameter of type Long. If we want to match a method with any number of parameters but having the fist parameter of type Long, we could use the following expression: @Pointcut("execution(* *.. find*(Long,..))")


You should combine a type pointcut with a method pointcut.

These pointcuts will do the work to find all public methods inside a class marked with an @Monitor annotation:

@Pointcut("within(@org.rejeev.Monitor *)")
public void beanAnnotatedWithMonitor() {}

@Pointcut("execution(public * *(..))")
public void publicMethod() {}

@Pointcut("publicMethod() && beanAnnotatedWithMonitor()")
public void publicMethodInsideAClassMarkedWithAtMonitor() {}

Advice the last pointcut that combines the first two and you're done!

If you're interested, I have written a cheat sheet with @AspectJ style here with a corresponding example document here.


Using annotations, as described in the question.

Annotation: @Monitor

Annotation on class, app/PagesController.java:

package app;
@Controller
@Monitor
public class PagesController {
    @RequestMapping(value = "/", method = RequestMethod.GET)
    public @ResponseBody String home() {
        return "w00t!";
    }
}

Annotation on method, app/PagesController.java:

package app;
@Controller
public class PagesController {
    @Monitor
    @RequestMapping(value = "/", method = RequestMethod.GET)
    public @ResponseBody String home() {
        return "w00t!";
    }
}

Custom annotation, app/Monitor.java:

package app;
@Component
@Target(value = {ElementType.METHOD, ElementType.TYPE})
@Retention(value = RetentionPolicy.RUNTIME)
public @interface Monitor {
}

Aspect for annotation, app/MonitorAspect.java:

package app;
@Component
@Aspect
public class MonitorAspect {
    @Before(value = "@within(app.Monitor) || @annotation(app.Monitor)")
    public void before(JoinPoint joinPoint) throws Throwable {
        LogFactory.getLog(MonitorAspect.class).info("monitor.before, class: " + joinPoint.getSignature().getDeclaringType().getSimpleName() + ", method: " + joinPoint.getSignature().getName());
    }

    @After(value = "@within(app.Monitor) || @annotation(app.Monitor)")
    public void after(JoinPoint joinPoint) throws Throwable {
        LogFactory.getLog(MonitorAspect.class).info("monitor.after, class: " + joinPoint.getSignature().getDeclaringType().getSimpleName() + ", method: " + joinPoint.getSignature().getName());
    }
}

Enable AspectJ, servlet-context.xml:

<aop:aspectj-autoproxy />

Include AspectJ libraries, pom.xml:

<artifactId>spring-aop</artifactId>
<artifactId>aspectjrt</artifactId>
<artifactId>aspectjweaver</artifactId>
<artifactId>cglib</artifactId>

Something like that:

@Before("execution(* com.yourpackage..*.*(..))")
public void monitor(JoinPoint jp) {
    if (jp.getTarget().getClass().isAnnotationPresent(Monitor.class)) {
       // perform the monitoring actions
    }
}

Note that you must not have any other advice on the same class before this one, because the annotations will be lost after proxying.


Use

@Before("execution(* (@YourAnnotationAtClassLevel *).*(..))")
    public void beforeYourAnnotation(JoinPoint proceedingJoinPoint) throws Throwable {
}