AspectJ advice not being executed through unit test

Question

I'm stumped. I'm trying to test an AspectJ class. My Aspect class gets picked up perfectly when I'm running my application. However, I seem to be unable to get any Aspect class to intercept any method within a test.

I am using Spring 3.2.2, AspectJ 1.7.2 and Maven 4.

Here is the simple test I'm working with:

The Test AspectJ class

package my.package.path.config;

import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.annotation.Pointcut;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@Aspect
public class TestAOP {
    private String message;

    public TestAOP() {
    }

    @Pointcut("execution(* my.package.path.TestAOPClient.relayMessage(..))")
    public void aopPointcut() {
    }

    @Around("aopPointcut()")
    public String monitor(ProceedingJoinPoint pjp) throws Throwable {
        String msg = (String)pjp.proceed();
        this.setMessage(msg);
        return msg;
    }

}

The class whose method is being intercepted

package my.package.path.config;

public class TestAOPClient {
    public String relayMessage(String msg) {
        return msg;
    }
}

The Test Class

package my.package.path.config;

import static org.hamcrest.Matchers.equalTo;
import static org.junit.Assert.assertThat;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.test.context.ContextConfiguration;
import org.springframework.test.context.junit4.AbstractJUnit4SpringContextTests;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
import org.springframework.test.context.web.WebAppConfiguration;

@Configuration
@ContextConfiguration(classes={WebConfig.class})
@RunWith(SpringJUnit4ClassRunner.class)
@WebAppConfiguration("src/main/java")
public class AopConfigTest extends AbstractJUnit4SpringContextTests {

     @Bean
     public TestAOP testAop() throws Exception {
        return new TestAOP();
     }

     @Test
     public void assertTestConfigIsActive() {
        TestAOPClient client = new TestAOPClient();
        client.relayMessage("hello");
        assertThat(((TestAOP)applicationContext.getBean("testAop")).getMessage(), equalTo("hello"));

    }
}

The WebConfig file

package my.package.path.web.context;
@Configuration
@EnableWebMvc
@EnableAspectJAutoProxy(proxyTargetClass=false)
@ComponentScan(value={"my.package.path.config", "my.package.path.web"})
public class WebConfig {

}

Invariably, I will get the assertion error

 Expected: "hello" but: was null

My WebApplicationContext seems to be picked up, since at runtime, I will get an ApplicationContext failed to load error if I specify a class that does not exist for my Aspect pointcut.

What am I missing?

Answer 1

It is kind of strange that you are using your unit test also as a @Configuration source.

You should remove the @Configuration annotation from the unit test and move the testAOP() bean definition to WebConfig. But most importantly the bean being advised must not be created manually, but by Spring:

@ContextConfiguration(classes={WebConfig.class})
@WebAppConfiguration("src/main/java")
public class AopConfigTest extends AbstractJUnit4SpringContextTests {

     @Autowired
     private TestAOP testAop;

     @Autowired
     private TestAOPClient client;

     @Test
     public void assertTestConfigIsActive() {
        client.relayMessage("hello");
        assertThat(((TestAOP)applicationContext.getBean("testAop")).getMessage(), 
            equalTo("hello"));
    }

}

Updated config with the bean definition:

@Configuration
@EnableWebMvc
@EnableAspectJAutoProxy(proxyTargetClass=false)
@ComponentScan(value={"my.package.path.config", "my.package.path.web"})
public class WebConfig {

    @Bean
    public TestAOP testAop() throws Exception {
        return new TestAOP();
    }

    @Bean
    public TestAOPClient testAopClient() throws Exception {
        return new TestAOPClient();
    }

}

If your target was to test whether the AOP configuration works and TestAOP is really a testing bean (not just a dummy name for this question), you can create a special TestConfig configuration class, move the bean definition there and use it from the test @ContextConfiguration(classes={WebConfig.class,TestConfig.class}).

Answer 2

Your pointcut configuration is wrong (package should be my.package.path.config to match your test client)

@Pointcut("execution(* my.package.path.TestAOPClient.relayMessage(..))")

and your client is

package my.package.path.config;

public class TestAOPClient {
...

change it to this

@Pointcut("execution(* my.package.path.config.TestAOPClient.relayMessage(..))")

should work.