SpringBoot factory already defined? - Nineya|java/go/python

Hii I just came across another problem with embeded-tomcat that I cannot resolve on my own. So I'd like to ask for assistance. I started an integration-test module within my repository and it seems to work fine actually. But if I execute the maven with "mvn clean install" from the parent I get the following error for each test in my integration-test module

I have absolutely no idea how and why this is happening.

You should be able to reproduce this when checking out the branch "jdk11" on this repository: https://github.com/Captain-P-Goldfish/SCIM-SDK

EDIT: here is my setup:

JDK: 11.0.6 maven 3.6.3 OS: Windows 10 Pro

it works if I execute "mvn clean install" directly in the integration-test module and from my IDE but it does not work if I execute the whole reactor.

EDIT 2:

this is not bound to windows. travis-ci build failed with the same message

java.lang.IllegalStateException: Failed to load ApplicationContext
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:132)
    at org.springframework.test.context.support.DefaultTestContext.getApplicationContext(DefaultTestContext.java:123)
    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:118)
    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:83)
    at org.springframework.boot.test.autoconfigure.SpringBootDependencyInjectionTestExecutionListener.prepareTestInstance(SpringBootDependencyInjectionTestExecutionListener.java:43)
    at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:244)
    at org.springframework.test.context.junit.jupiter.SpringExtension.postProcessTestInstance(SpringExtension.java:98)
    at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$invokeTestInstancePostProcessors$5(ClassBasedTestDescriptor.java:337)
    at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.executeAndMaskThrowable(ClassBasedTestDescriptor.java:342)
    at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$invokeTestInstancePostProcessors$6(ClassBasedTestDescriptor.java:337)
    at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:195)
    at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:177)
    at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1654)
    at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484)
    at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474)
    at java.base/java.util.stream.StreamSpliterators$WrappingSpliterator.forEachRemaining(StreamSpliterators.java:312)
    at java.base/java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:735)
    at java.base/java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:734)
    at java.base/java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:658)
    at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.invokeTestInstancePostProcessors(ClassBasedTestDescriptor.java:336)
    at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.instantiateAndPostProcessTestInstance(ClassBasedTestDescriptor.java:259)
    at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$testInstancesProvider$2(ClassBasedTestDescriptor.java:252)
    at java.base/java.util.Optional.orElseGet(Optional.java:369)
    at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$testInstancesProvider$3(ClassBasedTestDescriptor.java:251)
    at org.junit.jupiter.engine.execution.TestInstancesProvider.getTestInstances(TestInstancesProvider.java:29)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$prepare$0(TestMethodTestDescriptor.java:106)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.prepare(TestMethodTestDescriptor.java:105)
    at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.prepare(TestMethodTestDescriptor.java:69)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$prepare$1(NodeTestTask.java:107)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.prepare(NodeTestTask.java:107)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:75)
    at java.base/java.util.ArrayList.forEach(ArrayList.java:1540)
    at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
    at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
    at java.base/java.util.ArrayList.forEach(ArrayList.java:1540)
    at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
    at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
    at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
    at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
    at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
    at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51)
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:220)
    at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$6(DefaultLauncher.java:188)
    at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:202)
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:181)
    at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:128)
    at org.apache.maven.surefire.junitplatform.JUnitPlatformProvider.invokeAllTests(JUnitPlatformProvider.java:150)
    at org.apache.maven.surefire.junitplatform.JUnitPlatformProvider.invoke(JUnitPlatformProvider.java:124)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:566)
    at org.apache.maven.surefire.util.ReflectionUtils.invokeMethodWithArray2(ReflectionUtils.java:186)
    at org.apache.maven.surefire.booter.ProviderFactory$ProviderProxy.invoke(ProviderFactory.java:161)
    at org.apache.maven.surefire.booter.ProviderFactory.invokeProvider(ProviderFactory.java:84)
    at org.apache.maven.plugin.surefire.InPluginVMSurefireStarter.runSuitesInProcess(InPluginVMSurefireStarter.java:87)
    at org.apache.maven.plugin.surefire.AbstractSurefireMojo.executeProvider(AbstractSurefireMojo.java:1144)
    at org.apache.maven.plugin.surefire.AbstractSurefireMojo.executeAfterPreconditionsChecked(AbstractSurefireMojo.java:1002)
    at org.apache.maven.plugin.surefire.AbstractSurefireMojo.execute(AbstractSurefireMojo.java:848)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:137)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:210)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:156)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:148)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:117)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:81)
    at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:56)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:305)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:192)
    at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:105)
    at org.apache.maven.cli.MavenCli.execute(MavenCli.java:957)
    at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:289)
    at org.apache.maven.cli.MavenCli.main(MavenCli.java:193)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:566)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:282)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:225)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:406)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:347)
    at org.codehaus.classworlds.Launcher.main(Launcher.java:47)
Caused by: org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:156)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:544)
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:747)
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:315)
    at org.springframework.boot.test.context.SpringBootContextLoader.loadContext(SpringBootContextLoader.java:126)
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:99)
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:124)
    ... 96 more
Caused by: org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat
    at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:126)
    at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.<init>(TomcatWebServer.java:88)
    at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getTomcatWebServer(TomcatServletWebServerFactory.java:438)
    at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getWebServer(TomcatServletWebServerFactory.java:191)
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:180)
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:153)
    ... 104 more
Caused by: org.apache.catalina.LifecycleException: A child container failed during start
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:928)
    at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:262)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.core.StandardService.startInternal(StandardService.java:421)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:930)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.startup.Tomcat.start(Tomcat.java:468)
    at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:107)
    ... 109 more
Caused by: java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: A child container failed during start
    at java.base/java.util.concurrent.FutureTask.report(FutureTask.java:122)
    at java.base/java.util.concurrent.FutureTask.get(FutureTask.java:191)
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:916)
    ... 117 more
Caused by: org.apache.catalina.LifecycleException: A child container failed during start
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:928)
    at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:841)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374)
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
    at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
    at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:140)
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909)
    ... 117 more
Caused by: java.util.concurrent.ExecutionException: org.apache.catalina.LifecycleException: Failed to initialize component [org.apache.catalina.webresources.StandardRoot@5477cef1]
    at java.base/java.util.concurrent.FutureTask.report(FutureTask.java:122)
    at java.base/java.util.concurrent.FutureTask.get(FutureTask.java:191)
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:916)
    ... 125 more
Caused by: org.apache.catalina.LifecycleException: Failed to initialize component [org.apache.catalina.webresources.StandardRoot@5477cef1]
    at org.apache.catalina.util.LifecycleBase.handleSubClassException(LifecycleBase.java:440)
    at org.apache.catalina.util.LifecycleBase.init(LifecycleBase.java:139)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:173)
    at org.apache.catalina.core.StandardContext.resourcesStart(StandardContext.java:4805)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:4940)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1384)
    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1374)
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
    at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
    at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:140)
    at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:909)
    ... 125 more
Caused by: java.lang.Error: factory already defined
    at java.base/java.net.URL.setURLStreamHandlerFactory(URL.java:1207)
    at org.apache.catalina.webresources.TomcatURLStreamHandlerFactory.<init>(TomcatURLStreamHandlerFactory.java:130)
    at org.apache.catalina.webresources.TomcatURLStreamHandlerFactory.getInstanceInternal(TomcatURLStreamHandlerFactory.java:53)
    at org.apache.catalina.webresources.TomcatURLStreamHandlerFactory.register(TomcatURLStreamHandlerFactory.java:77)
    at org.apache.catalina.webresources.StandardRoot.registerURLStreamHandlerFactory(StandardRoot.java:701)
    at org.apache.catalina.webresources.StandardRoot.initInternal(StandardRoot.java:683)
    at org.apache.catalina.util.LifecycleBase.init(LifecycleBase.java:136)

Comment From: spencergibb

FWIW we see this in spring cloud too. We have this workaround scattered around a few places.

// FIXME: why do I need to do this? (fails in maven build without it.
TomcatURLStreamHandlerFactory.disable();

https://github.com/spring-cloud/spring-cloud-netflix/blob/aee83fb1132f33ae4bb798536c6e0cabf368c880/spring-cloud-netflix-eureka-client/src/test/java/org/springframework/cloud/netflix/eureka/config/EurekaConfigServerBootstrapConfigurationTests.java#L90-L91

Comment From: wilkinsona

Tomcat uses a static field to keep track of its URL stream handler factory and whether or not it needs to be registered. Being static, this means that the factory and keeping track of its registration is scoped to a class loader. The factory is registered with the JVM's URL class which is scoped to the JVM. Typically this difference in scoping does not cause a problem. In its default configuration, Surefire forks a single JVM per module in the reactor. Within this JVM a ClassLoader is created for the tests and their dependencies and the tests are executed. Once the tests are completed the JVM exits.

In your setup you have disabled forking. This means that Surefire reuses the main Maven JVM to execute the tests of every module. For each module it creates a ClassLoader for the module's tests and dependencies. This new ClassLoader means that a new TomcatURLStreamHandlerFactory is created and an attempt is made to register it. This works for the first module in the reactor where the JVM is fresh but fails for subsequent modules as the factory from the previous module is still registered. Unfortunately, the JVM does not allow a factory to be deregistered so, without resorting to reflection, there's nothing that Tomcat (or Spring Boot) can do to clean things up in a multi-classloader scenario such as this. You have a few options:

Use Surefire in its default configuration and fork a new JVM for each module's tests
Disable TomcatURLStreamHandlerFactory as @spencergibb showed above
Use reflection to clear URL's factory field

Comment From: hjohn

Hm, how useful is it to have Tomcat register this URL stream handler when it is embedded?

Comment From: wilkinsona

Tomcat uses it for all sorts of things, including, IIRC, its static resource handling.