spring 框架报错不直接问题

Question

我碰到了一个刁钻的问题：
我将一个能正常运行的spring 测试项目中的spring-jdbc 这个maven依赖故意注释掉。按道理来说它应该会直接报一个：java.lang.ClassNotFoundException: org.springframework.jdbc.core.JdbcTemplate。
但实际上，spring只给了一个不太相关的Index 0 out of bounds for length 0的错误信息：

E:\java\bin\java.exe -ea -Didea.test.cyclic.buffer.size=1048576 "-javaagent:E:\IntelliJ IDEA 2023.1.2\lib\idea_rt.jar=53447:E:\IntelliJ IDEA 2023.1.2\bin" -Dfile.encoding=UTF-8 -Dsun.stdout.encoding=UTF-8 -Dsun.stderr.encoding=UTF-8 -classpath "E:\IntelliJ IDEA 2023.1.2\lib\idea_rt.jar;E:\IntelliJ IDEA 2023.1.2\plugins\junit\lib\junit5-rt.jar;E:\IntelliJ IDEA 2023.1.2\plugins\junit\lib\junit-rt.jar;E:\WithLayui\Spring_Test\AopWIthMybatis\target\test-classes;E:\WithLayui\Spring_Test\AopWIthMybatis\target\classes;E:\Maven\junit\junit\4.13.2\junit-4.13.2.jar;E:\Maven\org\hamcrest\hamcrest-core\1.3\hamcrest-core-1.3.jar;E:\Maven\org\springframework\spring-context\5.2.21.RELEASE\spring-context-5.2.21.RELEASE.jar;E:\Maven\org\springframework\spring-aop\5.2.21.RELEASE\spring-aop-5.2.21.RELEASE.jar;E:\Maven\org\springframework\spring-beans\5.2.21.RELEASE\spring-beans-5.2.21.RELEASE.jar;E:\Maven\org\springframework\spring-core\5.2.21.RELEASE\spring-core-5.2.21.RELEASE.jar;E:\Maven\org\springframework\spring-jcl\5.2.21.RELEASE\spring-jcl-5.2.21.RELEASE.jar;E:\Maven\org\springframework\spring-expression\5.2.21.RELEASE\spring-expression-5.2.21.RELEASE.jar;E:\Maven\org\springframework\spring-test\5.2.21.RELEASE\spring-test-5.2.21.RELEASE.jar;E:\Maven\org\mybatis\mybatis\3.5.10\mybatis-3.5.10.jar;E:\Maven\com\mysql\mysql-connector-j\8.0.33\mysql-connector-j-8.0.33.jar;E:\Maven\com\google\protobuf\protobuf-java\3.21.9\protobuf-java-3.21.9.jar;E:\Maven\commons-dbcp\commons-dbcp\1.4\commons-dbcp-1.4.jar;E:\Maven\commons-pool\commons-pool\1.5.4\commons-pool-1.5.4.jar;E:\Maven\org\mybatis\mybatis-spring\2.1.0\mybatis-spring-2.1.0.jar;E:\Maven\org\projectlombok\lombok\1.18.20\lombok-1.18.20.jar;E:\Maven\log4j\log4j\1.2.17\log4j-1.2.17.jar;E:\Maven\org\aspectj\aspectjweaver\1.9.4\aspectjweaver-1.9.4.jar;E:\Maven\com\alibaba\druid\druid-wrapper\0.2.9\druid-wrapper-0.2.9.jar;E:\Maven\com\alibaba\druid\0.2.9\druid-0.2.9.jar" com.intellij.rt.junit.JUnitStarter -ideVersion5 -junit4 com.honphie.TestDemo1,test1
7月 18, 2023 2:21:46 上午 org.springframework.test.context.support.AbstractTestContextBootstrapper getDefaultTestExecutionListenerClassNames
信息: Loaded default TestExecutionListener class names from location [META-INF/spring.factories]: [org.springframework.test.context.web.ServletTestExecutionListener, org.springframework.test.context.support.DirtiesContextBeforeModesTestExecutionListener, org.springframework.test.context.support.DependencyInjectionTestExecutionListener, org.springframework.test.context.support.DirtiesContextTestExecutionListener, org.springframework.test.context.transaction.TransactionalTestExecutionListener, org.springframework.test.context.jdbc.SqlScriptsTestExecutionListener, org.springframework.test.context.event.EventPublishingTestExecutionListener]
7月 18, 2023 2:21:46 上午 org.springframework.test.context.support.AbstractTestContextBootstrapper getTestExecutionListeners
信息: Using TestExecutionListeners: [org.springframework.test.context.support.DirtiesContextBeforeModesTestExecutionListener@3891771e, org.springframework.test.context.support.DependencyInjectionTestExecutionListener@78ac1102, org.springframework.test.context.support.DirtiesContextTestExecutionListener@2de8284b, org.springframework.test.context.event.EventPublishingTestExecutionListener@396e2f39]
7月 18, 2023 2:21:46 上午 org.springframework.context.support.AbstractApplicationContext refresh
警告: Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanDefinitionStoreException: Failed to read candidate component class: file [E:\WithLayui\Spring_Test\AopWIthMybatis\target\classes\com\honphie\config\MybatisConfig.class]; nested exception is java.lang.IndexOutOfBoundsException: Index 0 out of bounds for length 0
7月 18, 2023 2:21:46 上午 org.springframework.test.context.TestContextManager prepareTestInstance
严重: Caught exception while allowing TestExecutionListener [org.springframework.test.context.support.DependencyInjectionTestExecutionListener@78ac1102] to prepare test instance [com.honphie.TestDemo1@5e5d171f]
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.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:248)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:227)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:289)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:291)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:246)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:97)
    at org.junit.runners.ParentRunner$4.run(ParentRunner.java:331)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:79)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:329)
    at org.junit.runners.ParentRunner.access$100(ParentRunner.java:66)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:293)
    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$3.evaluate(ParentRunner.java:306)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:413)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:69)
    at com.intellij.rt.junit.IdeaTestRunner$Repeater$1.execute(IdeaTestRunner.java:38)
    at com.intellij.rt.execution.junit.TestsRepeater.repeat(TestsRepeater.java:11)
    at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:35)
    at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:232)
    at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:55)
Caused by: org.springframework.beans.factory.BeanDefinitionStoreException: Failed to read candidate component class: file [E:\WithLayui\Spring_Test\AopWIthMybatis\target\classes\com\honphie\config\MybatisConfig.class]; nested exception is java.lang.IndexOutOfBoundsException: Index 0 out of bounds for length 0
    at org.springframework.context.annotation.ClassPathScanningCandidateComponentProvider.scanCandidateComponents(ClassPathScanningCandidateComponentProvider.java:457)
    at org.springframework.context.annotation.ClassPathScanningCandidateComponentProvider.findCandidateComponents(ClassPathScanningCandidateComponentProvider.java:316)
    at org.springframework.context.annotation.ClassPathBeanDefinitionScanner.doScan(ClassPathBeanDefinitionScanner.java:276)
    at org.springframework.context.annotation.ComponentScanAnnotationParser.parse(ComponentScanAnnotationParser.java:132)
    at org.springframework.context.annotation.ConfigurationClassParser.doProcessConfigurationClass(ConfigurationClassParser.java:296)
    at org.springframework.context.annotation.ConfigurationClassParser.processConfigurationClass(ConfigurationClassParser.java:250)
    at org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:207)
    at org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:175)
    at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:320)
    at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:237)
    at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanDefinitionRegistryPostProcessors(PostProcessorRegistrationDelegate.java:280)
    at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:96)
    at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:707)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:533)
    at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:127)
    at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:60)
    at org.springframework.test.context.support.AbstractDelegatingSmartContextLoader.delegateLoading(AbstractDelegatingSmartContextLoader.java:275)
    at org.springframework.test.context.support.AbstractDelegatingSmartContextLoader.loadContext(AbstractDelegatingSmartContextLoader.java:243)
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:99)
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:124)
    ... 27 more
Caused by: java.lang.IndexOutOfBoundsException: Index 0 out of bounds for length 0
    at java.base/jdk.internal.util.Preconditions.outOfBounds(Preconditions.java:100)
    at java.base/jdk.internal.util.Preconditions.outOfBoundsCheckIndex(Preconditions.java:106)
    at java.base/jdk.internal.util.Preconditions.checkIndex(Preconditions.java:302)
    at java.base/java.util.Objects.checkIndex(Objects.java:385)
    at java.base/java.util.ArrayList.get(ArrayList.java:427)
    at org.springframework.core.annotation.AnnotationTypeMappings.get(AnnotationTypeMappings.java:159)
    at org.springframework.core.annotation.TypeMappedAnnotation.of(TypeMappedAnnotation.java:599)
    at org.springframework.core.annotation.MergedAnnotation.of(MergedAnnotation.java:610)
    at org.springframework.core.type.classreading.MergedAnnotationReadingVisitor.visitEnd(MergedAnnotationReadingVisitor.java:96)
    at org.springframework.asm.ClassReader.readElementValues(ClassReader.java:2985)
    at org.springframework.asm.ClassReader.accept(ClassReader.java:582)
    at org.springframework.asm.ClassReader.accept(ClassReader.java:401)
    at org.springframework.core.type.classreading.SimpleMetadataReader.<init>(SimpleMetadataReader.java:49)
    at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:103)
    at org.springframework.core.type.classreading.CachingMetadataReaderFactory.getMetadataReader(CachingMetadataReaderFactory.java:123)
    at org.springframework.context.annotation.ClassPathScanningCandidateComponentProvider.scanCandidateComponents(ClassPathScanningCandidateComponentProvider.java:429)
    ... 46 more


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.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:248)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:227)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:289)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:291)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:246)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:97)
    at org.junit.runners.ParentRunner$4.run(ParentRunner.java:331)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:79)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:329)
    at org.junit.runners.ParentRunner.access$100(ParentRunner.java:66)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:293)
    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$3.evaluate(ParentRunner.java:306)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:413)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:69)
    at com.intellij.rt.junit.IdeaTestRunner$Repeater$1.execute(IdeaTestRunner.java:38)
    at com.intellij.rt.execution.junit.TestsRepeater.repeat(TestsRepeater.java:11)
    at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:35)
    at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:232)
    at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:55)
Caused by: org.springframework.beans.factory.BeanDefinitionStoreException: Failed to read candidate component class: file [E:\WithLayui\Spring_Test\AopWIthMybatis\target\classes\com\honphie\config\MybatisConfig.class]; nested exception is java.lang.IndexOutOfBoundsException: Index 0 out of bounds for length 0
    at org.springframework.context.annotation.ClassPathScanningCandidateComponentProvider.scanCandidateComponents(ClassPathScanningCandidateComponentProvider.java:457)
    at org.springframework.context.annotation.ClassPathScanningCandidateComponentProvider.findCandidateComponents(ClassPathScanningCandidateComponentProvider.java:316)
    at org.springframework.context.annotation.ClassPathBeanDefinitionScanner.doScan(ClassPathBeanDefinitionScanner.java:276)
    at org.springframework.context.annotation.ComponentScanAnnotationParser.parse(ComponentScanAnnotationParser.java:132)
    at org.springframework.context.annotation.ConfigurationClassParser.doProcessConfigurationClass(ConfigurationClassParser.java:296)
    at org.springframework.context.annotation.ConfigurationClassParser.processConfigurationClass(ConfigurationClassParser.java:250)
    at org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:207)
    at org.springframework.context.annotation.ConfigurationClassParser.parse(ConfigurationClassParser.java:175)
    at org.springframework.context.annotation.ConfigurationClassPostProcessor.processConfigBeanDefinitions(ConfigurationClassPostProcessor.java:320)
    at org.springframework.context.annotation.ConfigurationClassPostProcessor.postProcessBeanDefinitionRegistry(ConfigurationClassPostProcessor.java:237)
    at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanDefinitionRegistryPostProcessors(PostProcessorRegistrationDelegate.java:280)
    at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:96)
    at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:707)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:533)
    at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:127)
    at org.springframework.test.context.support.AbstractGenericContextLoader.loadContext(AbstractGenericContextLoader.java:60)
    at org.springframework.test.context.support.AbstractDelegatingSmartContextLoader.delegateLoading(AbstractDelegatingSmartContextLoader.java:275)
    at org.springframework.test.context.support.AbstractDelegatingSmartContextLoader.loadContext(AbstractDelegatingSmartContextLoader.java:243)
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContextInternal(DefaultCacheAwareContextLoaderDelegate.java:99)
    at org.springframework.test.context.cache.DefaultCacheAwareContextLoaderDelegate.loadContext(DefaultCacheAwareContextLoaderDelegate.java:124)
    ... 27 more
Caused by: java.lang.IndexOutOfBoundsException: Index 0 out of bounds for length 0
    at java.base/jdk.internal.util.Preconditions.outOfBounds(Preconditions.java:100)
    at java.base/jdk.internal.util.Preconditions.outOfBoundsCheckIndex(Preconditions.java:106)
    at java.base/jdk.internal.util.Preconditions.checkIndex(Preconditions.java:302)
    at java.base/java.util.Objects.checkIndex(Objects.java:385)
    at java.base/java.util.ArrayList.get(ArrayList.java:427)
    at org.springframework.core.annotation.AnnotationTypeMappings.get(AnnotationTypeMappings.java:159)
    at org.springframework.core.annotation.TypeMappedAnnotation.of(TypeMappedAnnotation.java:599)
    at org.springframework.core.annotation.MergedAnnotation.of(MergedAnnotation.java:610)
    at org.springframework.core.type.classreading.MergedAnnotationReadingVisitor.visitEnd(MergedAnnotationReadingVisitor.java:96)
    at org.springframework.asm.ClassReader.readElementValues(ClassReader.java:2985)
    at org.springframework.asm.ClassReader.accept(ClassReader.java:582)
    at org.springframework.asm.ClassReader.accept(ClassReader.java:401)
    at org.springframework.core.type.classreading.SimpleMetadataReader.<init>(SimpleMetadataReader.java:49)
    at org.springframework.core.type.classreading.SimpleMetadataReaderFactory.getMetadataReader(SimpleMetadataReaderFactory.java:103)
    at org.springframework.core.type.classreading.CachingMetadataReaderFactory.getMetadataReader(CachingMetadataReaderFactory.java:123)
    at org.springframework.context.annotation.ClassPathScanningCandidateComponentProvider.scanCandidateComponents(ClassPathScanningCandidateComponentProvider.java:429)
    ... 46 more


进程已结束,退出代码-1

Answer 1

这个问题可能是由于项目中其他部分依赖了spring-jdbc，导致即使注释掉了该依赖，其他部分仍然可以正常运行。而当你尝试使用spring-jdbc的功能时，由于该依赖被注释掉，所以会抛出相关的ClassNotFoundException异常。

至于错误信息中的"Index 0 out of bounds for length 0"错误，这可能是由于代码中某个地方使用了一个空数组，并且尝试访问该数组的第一个元素，导致出现了数组越界的错误。这个错误信息与注释掉spring-jdbc的依赖并没有直接关系，可能是一个偶然的错误。

如果你想要验证注释掉spring-jdbc依赖是否真的会导致ClassNotFoundException异常，可以尝试在项目中的其他地方使用spring-jdbc的功能，比如在某个Service类中注入JdbcTemplate并使用它执行数据库操作。这样应该能够触发ClassNotFoundException异常。