How to inject a spring bean into my @Aspect?

[jsinai]

This is a newbie question: I can successfully get the advice in my aspect class to fire based on my pointcuts; but the work my advice needs to do depends on access to a spring bean. Is there a pattern to follow to inject a bean into my @Aspect class? I've tried @Resource, @Autowired, ApplicationContextAware and nothing works.

Any help is appreciated.

[mpurdy1973]

This is a newbie question: I can successfully get the advice in my aspect class to fire based on my pointcuts; but the work my advice needs to do depends on access to a spring bean. Is there a pattern to follow to inject a bean into my @Aspect class? I've tried @Resource, @Autowired, ApplicationContextAware and nothing works.

Any help is appreciated.

you need to create properties in the aspect, and then use spring property injections to java set methods.

[jsinai]

Thanks for the tip. The setter injection worked (as you imply, it has to be in the application context xml file). However, by the time my advice fires, the bean is null. To avoid that problem, I needed to make the bean property static.

[mpurdy1973]

Thanks for the tip. The setter injection worked (as you imply, it has to be in the application context xml file). However, by the time my advice fires, the bean is null. To avoid that problem, I needed to make the bean property static.

if you create a class variable in the aspect for for the bean that you are setting, it shouldnt go out of scope.

[JeitEmgie]

This is a newbie question: I can successfully get the advice in my aspect class to fire based on my pointcuts; but the work my advice needs to do depends on access to a spring bean. Is there a pattern to follow to inject a bean into my @Aspect class? I've tried @Resource, @Autowired, ApplicationContextAware and nothing works.

Any help is appreciated.

If you don't mind mixing .aj aspect and @Aspect in your project :

package __SET_YOURS__;

import javax.annotation.Resource;
import java.lang.reflect.Field ;

import org.aspectj.lang.reflect.FieldSignature ;
import org.springframework.context.ApplicationContextAware;
import org.springframework.context.ApplicationContext;

public abstract aspect AbstractDependencyInjection implements ApplicationContextAware {

	private ApplicationContext	_ctx ;

	public abstract pointcut resourceAccess(); 

	Object around():resourceAccess(){
		FieldSignature fs = (FieldSignature)thisJoinPoint.getSignature();
		Field field = fs.getField();
		
		String beanid = field.getAnnotation(Resource.class).name();

		if (beanid.equals("")) {
			beanid = field.getName();
		}

		return this._ctx.getBean(beanid) ;
	}

	/*
	 * (non-Javadoc)
	 * @see org.springframework.context.ApplicationContextAware#setApplicationContext(org.springframework.context.ApplicationContext)
	 */
	public void setApplicationContext(ApplicationContext inContext) {
        this._ctx = inContext ;
      }
}

package __SET_YOURS__;

import javax.annotation.Resource;
import CLASS_THAT_WILL_HAVE_RESOURCE_INJECTED;

public aspect REAL_DependencyInjection extends AbstractDependencyInjection {
	public pointcut resourceAccess(): get(@Resource * *) && within(CLASS_THAT_WILL_HAVE_RESOURCE_INJECTED+) ;
}

(you can adapt pointcut definition at your criteria…)

@Aspect
public class CLASS_THAT_WILL_HAVE_RESOURCE_INJECTED {
        …
	@Resource(name="BEAN_ID_TO_INJECT")
	protected YourInjectedBeanClass yourInjectedField = null ;

        …
}

and in your applicationContext.xml

	<bean class="CLASS_THAT_WILL_HAVE_RESOURCE_INJECTED"  factory-method="aspectOf" />