NPE in AnnotationUtils.getValue [SPR-15642]

[spring-projects-issues]

Phil Webb opened SPR-15642 and commented

We've got a recent NPE in the Spring Boot build that Madhura helped to tracked down to this change:

f813712#diff-44945edabd4176dfd3966252ff4a589eL1322

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.NullPointerException

	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:979)
	at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:863)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:687)
	at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:848)
	at org.springframework.test.web.servlet.TestDispatcherServlet.service(TestDispatcherServlet.java:66)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
	at org.springframework.mock.web.MockFilterChain$ServletFilterProxy.doFilter(MockFilterChain.java:162)
	at org.springframework.mock.web.MockFilterChain.doFilter(MockFilterChain.java:129)
	at org.springframework.boot.actuate.trace.WebRequestTraceFilter.doFilterInternal(WebRequestTraceFilter.java:110)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.springframework.mock.web.MockFilterChain.doFilter(MockFilterChain.java:129)
	at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.springframework.mock.web.MockFilterChain.doFilter(MockFilterChain.java:129)
	at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:105)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.springframework.mock.web.MockFilterChain.doFilter(MockFilterChain.java:129)
	at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.springframework.mock.web.MockFilterChain.doFilter(MockFilterChain.java:129)
	at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:199)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.springframework.mock.web.MockFilterChain.doFilter(MockFilterChain.java:129)
	at org.springframework.boot.actuate.autoconfigure.MetricsFilter.doFilterInternal(MetricsFilter.java:106)
	at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
	at org.springframework.mock.web.MockFilterChain.doFilter(MockFilterChain.java:129)
	at org.springframework.test.web.servlet.MockMvc.perform(MockMvc.java:155)
	at org.springframework.boot.actuate.hypermedia.HypermediaEndpointDocumentation.metrics(HypermediaEndpointDocumentation.java:63)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
	at org.springframework.test.context.junit4.statements.RunBeforeTestExecutionCallbacks.evaluate(RunBeforeTestExecutionCallbacks.java:73)
	at org.springframework.test.context.junit4.statements.RunAfterTestExecutionCallbacks.evaluate(RunAfterTestExecutionCallbacks.java:83)
	at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75)
	at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86)
	at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84)
	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:251)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:98)
	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
	at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
	at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190)
	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
	at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:51)
	at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:237)
	at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
Caused by: java.lang.NullPointerException
	at org.springframework.core.annotation.AnnotationUtils.getValue(AnnotationUtils.java:1327)
	at org.springframework.core.annotation.AnnotationUtils.getValue(AnnotationUtils.java:1298)
	at org.springframework.hateoas.core.AnnotationMappingDiscoverer.getMappingFrom(AnnotationMappingDiscoverer.java:111)
	at org.springframework.hateoas.core.AnnotationMappingDiscoverer.getMapping(AnnotationMappingDiscoverer.java:73)
	at org.springframework.hateoas.mvc.ControllerLinkBuilder$CachingAnnotationMappingDiscoverer.getMapping(ControllerLinkBuilder.java:301)
	at org.springframework.hateoas.mvc.ControllerLinkBuilder.linkTo(ControllerLinkBuilder.java:119)
	at org.springframework.hateoas.mvc.ControllerLinkBuilder.linkTo(ControllerLinkBuilder.java:102)
	at org.springframework.boot.actuate.autoconfigure.EndpointWebMvcHypermediaManagementContextConfiguration$EndpointResource.<init>(EndpointWebMvcHypermediaManagementContextConfiguration.java:358)
	at org.springframework.boot.actuate.autoconfigure.EndpointWebMvcHypermediaManagementContextConfiguration$MvcEndpointAdvice.beforeBodyWrite(EndpointWebMvcHypermediaManagementContextConfiguration.java:299)
	at org.springframework.boot.actuate.autoconfigure.EndpointWebMvcHypermediaManagementContextConfiguration$MvcEndpointAdvice.beforeBodyWrite(EndpointWebMvcHypermediaManagementContextConfiguration.java:272)
	at org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyAdviceChain.processBody(RequestResponseBodyAdviceChain.java:135)
	at org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyAdviceChain.beforeBodyWrite(RequestResponseBodyAdviceChain.java:111)
	at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:230)
	at org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.handleReturnValue(RequestResponseBodyMethodProcessor.java:182)
	at org.springframework.web.method.support.HandlerMethodReturnValueHandlerComposite.handleReturnValue(HandlerMethodReturnValueHandlerComposite.java:83)
	at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:116)
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:860)
	at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:770)
	at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:86)
	at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:970)
	at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:904)
	at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:971)
	... 57 more

---

Affects: 5.0 RC2

Issue Links:

• Introduce null-safety of Spring Framework API [SPR-15540] #20099 Introduce null-safety of Spring Framework API

Referenced from: commits e6f1950, c675424

[spring-projects-issues]

Phil Webb commented

Juergen Hoeller I've restored the old behavior for a few methods and push the fix. I couldn't really see a way to get the Boot build green again without them. If they really need to go I think we should add some Assert.notNull checks. We'll also need to get an upstream fix in Spring Hateoas since that was the project making the call.

I'll leave this issue open for now so you can review.

Cheers!

[spring-projects-issues]

Phil Webb commented

Here's another one:

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'cityRepository': Invocation of init method failed; nested exception is java.lang.NullPointerException
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1716)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:575)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:492)
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:306)
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:233)
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:304)
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:731)
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:862)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:543)
	at org.springframework.boot.autoconfigure.data.mongo.MongoReactiveAndBlockingRepositoriesAutoConfigurationTests.shouldCreateInstancesForReactiveAndBlockingRepositories(MongoReactiveAndBlockingRepositoriesAutoConfigurationTests.java:64)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
	at org.junit.internal.runners.statements.RunAfters.evaluate(RunAfters.java:27)
	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:78)
	at org.junit.runners.BlockJUnit4ClassRunner.runChild(BlockJUnit4ClassRunner.java:57)
	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
	at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86)
	at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:678)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)
Caused by: java.lang.NullPointerException
	at org.springframework.core.annotation.AnnotationUtils.getValue(AnnotationUtils.java:1327)
	at org.springframework.core.annotation.AnnotationUtils.getValue(AnnotationUtils.java:1298)
	at org.springframework.data.mongodb.repository.query.MongoQueryMethod.getAnnotatedQuery(MongoQueryMethod.java:107)
	at org.springframework.data.mongodb.repository.query.MongoQueryMethod.hasAnnotatedQuery(MongoQueryMethod.java:96)
	at org.springframework.data.mongodb.repository.support.MongoRepositoryFactory$MongoQueryLookupStrategy.resolveQuery(MongoRepositoryFactory.java:185)
	at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.lambda$null$0(RepositoryFactorySupport.java:409)
	at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193)
	at java.util.Iterator.forEachRemaining(Iterator.java:116)
	at java.util.Collections$UnmodifiableCollection$1.forEachRemaining(Collections.java:1049)
	at java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1801)
	at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)
	at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471)
	at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708)
	at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
	at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499)
	at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.lambda$new$2(RepositoryFactorySupport.java:411)
	at java.util.Optional.map(Optional.java:215)
	at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.<init>(RepositoryFactorySupport.java:402)
	at org.springframework.data.repository.core.support.RepositoryFactorySupport.getRepository(RepositoryFactorySupport.java:240)
	at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.lambda$afterPropertiesSet$2(RepositoryFactoryBeanSupport.java:257)
	at org.springframework.data.util.Lazy.get(Lazy.java:62)
	at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.afterPropertiesSet(RepositoryFactoryBeanSupport.java:260)
	at org.springframework.data.mongodb.repository.support.MongoRepositoryFactoryBean.afterPropertiesSet(MongoRepositoryFactoryBean.java:117)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1773)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1712)
	... 34 more

[spring-projects-issues]

Andy Wilkinson commented

A number of projects are already in the process of adapting, for example:

spring-projects/spring-hateoas#595
spring-attic/spring-data-solr@b2b5a3f
spring-projects/spring-data-mongodb@a85855a

[spring-projects-issues]

Juergen Hoeller commented

I'm OK with restoring our historic leniency in getValue and getDefaultValue, and also for the annotation type argument in findAnnotation. Phil, I've simply added corresponding @Nullable declarations following up on your commit there, so that we're warning-free again.

However, I do care about synthesizeAnnotation not just carrying through a null anymore, in order to guarantee a non-null return value there. This would otherwise force that method to declare @Nullable on its return value, exposing the unclean nullability to all regular callers. So I went with an assertion for that particular case instead.

FWIW, synthesizeAnnotation is also more recent - 4.2+, more broadly in 4.3 - so I hope less existing code is affected there. Moving forward, we should not introduce such overly lenient null handling in new APIs anymore. And it doesn't hurt if affected projects adapt their code right away, even if leniency has been restored for those existing AnnotationUtils methods. Such adaptations are still compatible with 4.3.x anyway, just cleaner on the caller's site (never passing in null), so it's not an issue for cross-version compatibility of dependent projects.