Mockito is unable to load the default implementation of class that is a part of Mockito distribution #5064
Description
I wrote the junit mockito testcases for my spring boot application controllers and service classes. The test cases are executing in one machine and another machine not working and getting the issue as below.
The Java, gradle ,intellji and windows versions are same on the both machines.
Issue:
2025-10-16T02:23:11.206 ERROR o.s.boot.SpringApplication - Application run failed
java.lang.IllegalStateException: Could not initialize plugin: interface org.mockito.plugins.MockMaker (alternate: null)
at org.mockito.internal.configuration.plugins.PluginLoader$1.invoke(PluginLoader.java:85)
at jdk.proxy3/jdk.proxy3.$Proxy84.isTypeMockable(Unknown Source)
at org.mockito.internal.util.MockUtil.typeMockabilityOf(MockUtil.java:78)
at org.mockito.internal.util.MockCreationValidator.validateType(MockCreationValidator.java:22)
at org.mockito.internal.creation.MockSettingsImpl.validatedSettings(MockSettingsImpl.java:275)
at org.mockito.internal.creation.MockSettingsImpl.build(MockSettingsImpl.java:236)
at org.mockito.internal.MockitoCore.mock(MockitoCore.java:82)
at org.mockito.Mockito.mock(Mockito.java:2198)
at org.springframework.test.context.bean.override.mockito.MockitoBeanOverrideHandler.createMock(MockitoBeanOverrideHandler.java:136)
at org.springframework.test.context.bean.override.mockito.MockitoBeanOverrideHandler.createOverrideInstance(MockitoBeanOverrideHandler.java:119)
at org.springframework.test.context.bean.override.BeanOverrideHandler.createOverrideInstance(BeanOverrideHandler.java:324)
at org.springframework.test.context.bean.override.BeanOverrideBeanFactoryPostProcessor.replaceOrCreateBean(BeanOverrideBeanFactoryPostProcessor.java:220)
at org.springframework.test.context.bean.override.BeanOverrideBeanFactoryPostProcessor.registerBeanOverride(BeanOverrideBeanFactoryPostProcessor.java:115)
at org.springframework.test.context.bean.override.BeanOverrideBeanFactoryPostProcessor.postProcessBeanFactory(BeanOverrideBeanFactoryPostProcessor.java:100)
at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:363)
at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:197)
at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:791)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:609)
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:752)
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:439)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:318)
at org.springframework.boot.test.context.SpringBootContextLoader.lambda$loadContext$3(SpringBootContextLoader.java:144)
at org.springframework.util.function.ThrowingSupplier.get(ThrowingSupplier.java:58)
at org.springframework.util.function.ThrowingSupplier.get(ThrowingSupplier.java:46)
at org.springframework.boot.SpringApplication.withHook(SpringApplication.java:1461)
at org.springframework.boot.test.context.SpringBootContextLoader$ContextLoaderHook.run(SpringBootContextLoader.java:563)
at org.springframework.boot.test.context.SpringBootContextLoader.loadContext(SpringBootContextLoader.java:144)
at org.springframework.boot.test.context.SpringBootContextLoader.loadContext(SpringBootContextLoader.java:110)
at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:225)
at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:152)
at org.springframework.test.context.support.DefaultTestContext.getApplicationContext(DefaultTestContext.java:130)
at org.springframework.test.context.bean.override.BeanOverrideTestExecutionListener.injectFields(BeanOverrideTestExecutionListener.java:99)
at org.springframework.test.context.bean.override.BeanOverrideTestExecutionListener.prepareTestInstance(BeanOverrideTestExecutionListener.java:70)
at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:260)
at org.springframework.test.context.junit.jupiter.SpringExtension.postProcessTestInstance(SpringExtension.java:159)
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$invokeTestInstancePostProcessors$10(ClassBasedTestDescriptor.java:383)
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.executeAndMaskThrowable(ClassBasedTestDescriptor.java:388)
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$invokeTestInstancePostProcessors$11(ClassBasedTestDescriptor.java:382)
at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.accept(ForEachOps.java:184)
at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:179)
at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1708)
at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509)
at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499)
at java.base/java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:151)
at java.base/java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:174)
at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
at java.base/java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:596)
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.invokeTestInstancePostProcessors(ClassBasedTestDescriptor.java:382)
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$instantiateAndPostProcessTestInstance$6(ClassBasedTestDescriptor.java:293)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.instantiateAndPostProcessTestInstance(ClassBasedTestDescriptor.java:292)
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$testInstancesProvider$4(ClassBasedTestDescriptor.java:281)
at java.base/java.util.Optional.orElseGet(Optional.java:364)
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$testInstancesProvider$5(ClassBasedTestDescriptor.java:280)
at org.junit.jupiter.engine.execution.TestInstancesProvider.getTestInstances(TestInstancesProvider.java:27)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$prepare$0(TestMethodTestDescriptor.java:112)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.prepare(TestMethodTestDescriptor.java:111)
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.prepare(TestMethodTestDescriptor.java:69)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$prepare$2(NodeTestTask.java:128)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.prepare(NodeTestTask.java:128)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:95)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1596)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:41)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$6(NodeTestTask.java:160)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:146)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$9(NodeTestTask.java:144)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:143)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:100)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1596)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:41)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$6(NodeTestTask.java:160)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:146)
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$9(NodeTestTask.java:144)
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:143)
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:100)
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:35)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:54)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:201)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:170)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:94)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.lambda$execute$0(EngineExecutionOrchestrator.java:59)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.withInterceptedStreams(EngineExecutionOrchestrator.java:142)
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:58)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:103)
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:85)
at org.junit.platform.launcher.core.DelegatingLauncher.execute(DelegatingLauncher.java:47)
at org.junit.platform.launcher.core.InterceptingLauncher.lambda$execute$1(InterceptingLauncher.java:39)
at org.junit.platform.launcher.core.ClasspathAlignmentCheckingLauncherInterceptor.intercept(ClasspathAlignmentCheckingLauncherInterceptor.java:25)
at org.junit.platform.launcher.core.InterceptingLauncher.execute(InterceptingLauncher.java:38)
at org.junit.platform.launcher.core.DelegatingLauncher.execute(DelegatingLauncher.java:47)
at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor$CollectAllTestClassesExecutor.processAllTestClasses(JUnitPlatformTestClassProcessor.java:124)
at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor$CollectAllTestClassesExecutor.access$000(JUnitPlatformTestClassProcessor.java:99)
at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor.stop(JUnitPlatformTestClassProcessor.java:94)
at org.gradle.api.internal.tasks.testing.SuiteTestClassProcessor.stop(SuiteTestClassProcessor.java:63)
at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103)
at java.base/java.lang.reflect.Method.invoke(Method.java:580)
at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:36)
at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
at org.gradle.internal.dispatch.ContextClassLoaderDispatch.dispatch(ContextClassLoaderDispatch.java:33)
at org.gradle.internal.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:92)
at jdk.proxy2/jdk.proxy2.$Proxy6.stop(Unknown Source)
at org.gradle.api.internal.tasks.testing.worker.TestWorker$3.run(TestWorker.java:200)
at org.gradle.api.internal.tasks.testing.worker.TestWorker.executeAndMaintainThreadName(TestWorker.java:132)
at org.gradle.api.internal.tasks.testing.worker.TestWorker.execute(TestWorker.java:103)
at org.gradle.api.internal.tasks.testing.worker.TestWorker.execute(TestWorker.java:63)
at org.gradle.process.internal.worker.child.ActionExecutionWorker.execute(ActionExecutionWorker.java:56)
at org.gradle.process.internal.worker.child.SystemApplicationClassLoaderWorker.call(SystemApplicationClassLoaderWorker.java:122)
at org.gradle.process.internal.worker.child.SystemApplicationClassLoaderWorker.call(SystemApplicationClassLoaderWorker.java:72)
at worker.org.gradle.process.internal.worker.GradleWorkerMain.run(GradleWorkerMain.java:69)
at worker.org.gradle.process.internal.worker.GradleWorkerMain.main(GradleWorkerMain.java:74)
Caused by: java.lang.IllegalStateException: Internal problem occurred, please report it. Mockito is unable to load the default implementation of class that is a part of Mockito distribution. Failed to load interface org.mockito.plugins.MockMaker
at org.mockito.internal.configuration.plugins.DefaultMockitoPlugins.create(DefaultMockitoPlugins.java:105)
at org.mockito.internal.configuration.plugins.DefaultMockitoPlugins.getDefaultPlugin(DefaultMockitoPlugins.java:79)
at org.mockito.internal.configuration.plugins.PluginLoader.loadPlugin(PluginLoader.java:75)
at org.mockito.internal.configuration.plugins.PluginLoader.loadPlugin(PluginLoader.java:49)
at org.mockito.internal.configuration.plugins.PluginRegistry.(PluginRegistry.java:29)
at org.mockito.internal.configuration.plugins.Plugins.(Plugins.java:26)
at org.mockito.internal.MockitoCore.(MockitoCore.java:71)
at org.mockito.Mockito.(Mockito.java:1777)
at org.springframework.test.context.bean.override.mockito.MockReset.withSettings(MockReset.java:84)
at org.springframework.test.context.bean.override.mockito.MockitoBeanOverrideHandler.createMock(MockitoBeanOverrideHandler.java:124)
... 112 common frames omitted
Caused by: java.lang.reflect.InvocationTargetException: null
at java.base/jdk.internal.reflect.DirectConstructorHandleAccessor.newInstance(DirectConstructorHandleAccessor.java:74)
at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:502)
at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:486)
at org.mockito.internal.configuration.plugins.DefaultMockitoPlugins.create(DefaultMockitoPlugins.java:103)
... 121 common frames omitted
Caused by: org.mockito.exceptions.base.MockitoInitializationException:
Could not initialize inline Byte Buddy mock maker.
It appears as if your JDK does not supply a working agent attachment mechanism.
Java : 21
JVM vendor name : Amazon.com Inc.
JVM vendor version : 21.0.8+9-LTS
JVM name : OpenJDK 64-Bit Server VM
JVM version : 21.0.8+9-LTS
JVM info : mixed mode, sharing
OS name : Windows 11
OS version : 10.0
at org.mockito.internal.creation.bytebuddy.InlineDelegateByteBuddyMockMaker.(InlineDelegateByteBuddyMockMaker.java:275)
at org.mockito.internal.creation.bytebuddy.InlineByteBuddyMockMaker.(InlineByteBuddyMockMaker.java:23)
at java.base/jdk.internal.reflect.DirectConstructorHandleAccessor.newInstance(DirectConstructorHandleAccessor.java:62)
... 124 common frames omitted
Caused by: java.lang.IllegalArgumentException: null
at java.instrument/sun.instrument.InstrumentationImpl.appendToClassLoaderSearch0(Native Method)
at java.instrument/sun.instrument.InstrumentationImpl.appendToBootstrapClassLoaderSearch(InstrumentationImpl.java:280)
at org.mockito.internal.creation.bytebuddy.InlineDelegateByteBuddyMockMaker.(InlineDelegateByteBuddyMockMaker.java:175)
... 126 common frames omitted