JUnit Test - java.lang.Exception: No runnable methods

JUnit Test 시 initializationError 가 발생했다면 아래 항목을 한번 확인해보자.

 1) 메서드에 @Test 어노테이션이 없는 경우

 2) org.junit.Test 이 아닌 다른 어노테이션을 Import 했을 경우

 

둘 중 한 가지에 해당한다면 아래와 같은 Failure Trace를 발견했을 것이다.

java.lang.Exception: No runnable methods
	at org.junit.runners.BlockJUnit4ClassRunner.validateInstanceMethods(BlockJUnit4ClassRunner.java:191)
	at org.junit.runners.BlockJUnit4ClassRunner.collectInitializationErrors(BlockJUnit4ClassRunner.java:128)
	at org.junit.runners.ParentRunner.validate(ParentRunner.java:416)
	at org.junit.runners.ParentRunner.<init>(ParentRunner.java:84)
	at org.junit.runners.BlockJUnit4ClassRunner.<init>(BlockJUnit4ClassRunner.java:65)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.<init>(SpringJUnit4ClassRunner.java:137)
	at org.springframework.test.context.junit4.SpringRunner.<init>(SpringRunner.java:49)
	at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at java.base/jdk.internal.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:500)
	at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:481)
	at org.junit.internal.builders.AnnotatedBuilder.buildRunner(AnnotatedBuilder.java:104)
	at org.junit.vintage.engine.discovery.DefensiveAllDefaultPossibilitiesBuilder$DefensiveAnnotatedBuilder.buildRunner(DefensiveAllDefaultPossibilitiesBuilder.java:113)
	at org.junit.internal.builders.AnnotatedBuilder.runnerForClass(AnnotatedBuilder.java:86)
	at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59)
	at org.junit.internal.builders.AllDefaultPossibilitiesBuilder.runnerForClass(AllDefaultPossibilitiesBuilder.java:26)
	at org.junit.vintage.engine.discovery.DefensiveAllDefaultPossibilitiesBuilder.runnerForClass(DefensiveAllDefaultPossibilitiesBuilder.java:56)
	at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:59)
	at org.junit.vintage.engine.discovery.ClassSelectorResolver.resolveTestClass(ClassSelectorResolver.java:66)
	at org.junit.vintage.engine.discovery.ClassSelectorResolver.resolve(ClassSelectorResolver.java:47)
	at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.lambda$resolve$2(EngineDiscoveryRequestResolution.java:129)
	at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:195)
	at java.base/java.util.ArrayList$ArrayListSpliterator.tryAdvance(ArrayList.java:1631)
	at java.base/java.util.stream.ReferencePipeline.forEachWithCancel(ReferencePipeline.java:127)
	at java.base/java.util.stream.AbstractPipeline.copyIntoWithCancel(AbstractPipeline.java:502)
	at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:488)
	at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474)
	at java.base/java.util.stream.FindOps$FindOp.evaluateSequential(FindOps.java:150)
	at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
	at java.base/java.util.stream.ReferencePipeline.findFirst(ReferencePipeline.java:543)
	at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.resolve(EngineDiscoveryRequestResolution.java:174)
	at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.resolve(EngineDiscoveryRequestResolution.java:120)
	at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.resolveCompletely(EngineDiscoveryRequestResolution.java:87)
	at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolution.run(EngineDiscoveryRequestResolution.java:80)
	at org.junit.platform.engine.support.discovery.EngineDiscoveryRequestResolver.resolve(EngineDiscoveryRequestResolver.java:112)
	at org.junit.vintage.engine.discovery.VintageDiscoverer.discover(VintageDiscoverer.java:42)
	at org.junit.vintage.engine.VintageTestEngine.discover(VintageTestEngine.java:62)
	at org.junit.platform.launcher.core.DefaultLauncher.discoverEngineRoot(DefaultLauncher.java:177)
	at org.junit.platform.launcher.core.DefaultLauncher.discoverRoot(DefaultLauncher.java:164)
	at org.junit.platform.launcher.core.DefaultLauncher.discover(DefaultLauncher.java:120)
	at org.eclipse.jdt.internal.junit5.runner.JUnit5TestReference.<init>(JUnit5TestReference.java:45)
	at org.eclipse.jdt.internal.junit5.runner.JUnit5TestLoader.createUnfilteredTest(JUnit5TestLoader.java:76)
	at org.eclipse.jdt.internal.junit5.runner.JUnit5TestLoader.createTest(JUnit5TestLoader.java:66)
	at org.eclipse.jdt.internal.junit5.runner.JUnit5TestLoader.loadTests(JUnit5TestLoader.java:53)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:526)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:770)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:464)
	at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:210)