Java - Spring AOP Pointcut not working

Question

Can someone pinpoint what am I doing wrong? How can I make my Aspect run?

I have written this code following some examples:

@Aspect
public class MethodLogger {

    private Logger log = Logger.getLogger(getClass().getName());

    @Pointcut("execution(* setHeight(..))")
    public void log(JoinPoint point) {
        log.info(point.getSignature().getName() + " called...");

    }
}

My simple test class:

public class ChairImpl implements Chair {
    int height;
    public ChairImpl(){}

    public int getHeight() {
        return height;
    }
    public void setHeight(int height) {
        this.height = height;
    }


}

My Spring xml config:

<?xml version="1.0" encoding="UTF-8"?>
    <beans xmlns="http://www.springframework.org/schema/beans"
        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
        xmlns:p="http://www.springframework.org/schema/p"
        xmlns:context="http://www.springframework.org/schema/context"
        xmlns:aop="http://www.springframework.org/schema/aop" 
        xsi:schemaLocation="
            http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd 
            http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd 
            http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd"
        default-destroy-method="destroy"
        default-init-method="afterPropertiesSet"
        default-autowire="byName"
>

<aop:aspectj-autoproxy>
        <aop:include name="MethodLogger"/>
    </aop:aspectj-autoproxy>

    <bean id="logger1" class="lab.MethodLogger"/>

    <bean id="chair1" 
    class="lab.test.ChairImpl"
    >
        <property name="height" value="10"/>
    </bean>

</beans>

And my main method:

public class Main {
    public static void main(String[] args){
        ApplicationContext context = new ClassPathXmlApplicationContext("spec.xml");
        ((AbstractApplicationContext) context).close();

    }
}

So before running my project, Eclipse gives me this error(it marks red void word for log method):

Pointcuts without an if() expression should have an empty method body

When I run, my program runs without errors, because it looks like log method never ran. So how could I fix it so it would run and output log? I tried simply to print test text from that method, but it never does, so it means it never runs. What am I missing here?

In documentation it only writes vague examples like:

@Pointcut("execution(* transfer(..))")// the pointcut expression
private void anyOldTransfer() {}// the pointcut signature

But I find it hard to understand how to actually use it to see results.

You have only part of the aspect. You have the where but miss the when (around, before etc). Next to the pointcut (which should always be on an emtpy method) you also need a method which represents the advice. I.e. a method annotated with `@Before`. — M. Deinum, Jan 17 '14 at 13:41

score 1 · Accepted Answer · answered Jan 17 '14 at 13:47

You can try an anonymous pointcut this way:

@Before("execution(* setHeight(..))")
public void log(JoinPoint point) {
    log.info(point.getSignature().getName() + " called...");

}

or give your pointcut a name and use it this way:

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

@Before("setters()") 
public void log(JoinPoint point) {
...
}

Java - Spring AOP Pointcut not working

1 Answers1