Unable to Autowire a dependency into an @AspectJ component [SPR-8726]

[spring-projects-issues]

Brandon M. opened SPR-8726 and commented

I have an @AspectJ component that has an autowired dependency which is not getting injected into the component. When the aspect attempts to use the autowired dependency, it encounters an NPE. See attached project for example along with failing test case.

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Affects: 3.1 M2

Attachments:

• TestProject.zip (12.40 kB)

[spring-projects-issues]

Brandon M. commented

Any updates, or chance this will get in for 3.1 release?

[spring-projects-issues]

Chris Beams commented

Hi Brandon,

First, thanks for the reproduction project. It makes this sort of thing very straightforward to assess. I've added this to our 'issues' github repository here: https://github.com/SpringSource/spring-framework-issues/tree/master/SPR-8726

In the future, you may want to streamline the process of creating these reproduction projects by following the instructions here: https://github.com/SpringSource/spring-framework-issues#readme

As for your issue:

1. I never encountered an NPE
2. Your AuditService was not being managed by the Spring container, thus there was no opportunity for Spring to apply your AuditAspect to its @Auditable method.

The solution to (2) above is to simply make sure that AuditService is marked as a @Component or otherwise registered as a Spring bean. See this diff: spring-attic/spring-framework-issues@ad27d43

With this diff applied, your tests are green.

If you actually need to have aspects applied to non-Spring managed beans (such as domain objects / entities), consider using @Configurable and load-time weaving. See the reference documentation for details on those.

Finally, you're using @ImportResource to bring in aop.xml, which does nothing more than declare <aop:aspectj-autoproxy>. You might be interested to know that as of Spring 3.1 RC1, @EnableAspectJAutoProxy is now available. See the Javadoc: http://static.springsource.org/spring/docs/3.1.x/javadoc-api/org/springframework/context/annotation/EnableAspectJAutoProxy.html

Hope that helps!

Chris

[spring-projects-issues]

Brandon M. commented

I just grabbed your update here (spring-attic/spring-framework-issues@ad27d43#diff-0) and still get a NPE.

java.lang.NullPointerException
at org.mycompany.audit.AuditAspectTests.auditedCall_aroundBody1$advice(AuditAspectTests.java:74)
at org.mycompany.audit.AuditAspectTests.testAudit(AuditAspectTests.java:28)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:44)
at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:15)
at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:41)
at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:20)
at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:74)
at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:82)
at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:72)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:240)
at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:50)
at org.junit.runners.ParentRunner$3.run(ParentRunner.java:193)
at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:52)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:191)
at org.junit.runners.ParentRunner.access$000(ParentRunner.java:42)
at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:184)
at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
at org.junit.runners.ParentRunner.run(ParentRunner.java:236)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:180)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:467)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:683)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:390)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:197)

[spring-projects-issues]

Chris Beams commented

Brandon,

Here's how I am running the test:

cbeams@anakata:~/Work/spring-framework/spring-framework-issues/SPR-8726[master]
$ mvn --version
Apache Maven 3.0.3 (r1075438; 2011-02-28 09:31:09-0800)
Maven home: /usr/share/maven
Java version: 1.6.0_29, vendor: Apple Inc.
Java home: /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home
Default locale: en_US, platform encoding: MacRoman
OS name: "mac os x", version: "10.7.2", arch: "x86_64", family: "mac"

cbeams@anakata:~/Work/spring-framework/spring-framework-issues/SPR-8726[master]
$ mvn clean test
[...]
Results :

Tests run: 1, Failures: 0, Errors: 0, Skipped: 0

...
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------

What is different about your setup?

[spring-projects-issues]

Brandon M. commented

Ahh, my underlying issue was that I was adding the AspectJ nature to my Eclipse project. Without the AspectJ project nature, my tests now pass. Thanks and have a Happy Thanksgiving!

[spring-projects-issues]

Chris Beams commented

you too, cheers!