有没有 java 大神啊！

跟着视频敲了 mybatisplus 的入门案例，检查很多遍，就是运行不了。

. ____ _ __ _ _
/\ / _' __ _ ()_ __ __ _ \ \ \
( ( )__ | '_ | '| | ' / ` | \ \ \
\/ _)| |)| | | | | || (_| | ) ) ) )
' || .|| ||| |_, | / / / /
=========||==============|_/=//_//

:: Spring Boot :: (v3.3.4)

2024-09-22T20:58:55.910+08:00 INFO 18108 --- [ main] com.itheima.test : Starting test using Java 17.0.11 with PID 18108 (started by linxin in D:\java\MybatisPlus_quickstart)
2024-09-22T20:58:55.911+08:00 INFO 18108 --- [ main] com.itheima.test : No active profile set, falling back to 1 default profile: "default"
2024-09-22T20:58:56.305+08:00 WARN 18108 --- [ main] o.m.s.mapper.ClassPathMapperScanner : No MyBatis mapper was found in '[com.itheima.dao.BookDao]' package. Please check your configuration.
_ _ |_ _ |. ___ _ | _
| | |/|)(| | |\ |)||_|_
/ |
3.5.7
2024-09-22T20:58:57.175+08:00 INFO 18108 --- [ main] com.itheima.test : Started test in 1.536 seconds (process running for 2.733)
2024-09-22T20:58:57.183+08:00 WARN 18108 --- [ main] o.s.test.context.TestContextManager : Caught exception while allowing TestExecutionListener [org.springframework.test.context.support.DependencyInjectionTestExecutionListener] to prepare test instance [com.itheima.test@1f9f381d]

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.itheima.test': Injection of resource dependencies failed
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessProperties(CommonAnnotationBeanPostProcessor.java:371) ~[spring-context-6.1.13.jar:6.1.13]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1439) ~[spring-beans-6.1.13.jar:6.1.13]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireBeanProperties(AbstractAutowireCapableBeanFactory.java:398) ~[spring-beans-6.1.13.jar:6.1.13]
at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:143) ~[spring-test-6.1.13.jar:6.1.13]
at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:98) ~[spring-test-6.1.13.jar:6.1.13]
at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:260) ~[spring-test-6.1.13.jar:6.1.13]
at org.springframework.test.context.junit.jupiter.SpringExtension.postProcessTestInstance(SpringExtension.java:163) ~[spring-test-6.1.13.jar:6.1.13]
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$invokeTestInstancePostProcessors$10(ClassBasedTestDescriptor.java:378) ~[junit-jupiter-engine-5.10.3.jar:5.10.3]
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.executeAndMaskThrowable(ClassBasedTestDescriptor.java:383) ~[junit-jupiter-engine-5.10.3.jar:5.10.3]
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$invokeTestInstancePostProcessors$11(ClassBasedTestDescriptor.java:378) ~[junit-jupiter-engine-5.10.3.jar:5.10.3]
at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197) ~[na:na]
at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:179) ~[na:na]
at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625) ~[na:na]
at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:509) ~[na:na]
at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:499) ~[na:na]
at java.base/java.util.stream.StreamSpliterators$WrappingSpliterator.forEachRemaining(StreamSpliterators.java:310) ~[na:na]
at java.base/java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:735) ~[na:na]
at java.base/java.util.stream.Streams$ConcatSpliterator.forEachRemaining(Streams.java:734) ~[na:na]
at java.base/java.util.stream.ReferencePipeline$Head.forEach(ReferencePipeline.java:762) ~[na:na]
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.invokeTestInstancePostProcessors(ClassBasedTestDescriptor.java:377) ~[junit-jupiter-engine-5.10.3.jar:5.10.3]
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$instantiateAndPostProcessTestInstance$6(ClassBasedTestDescriptor.java:290) ~[junit-jupiter-engine-5.10.3.jar:5.10.3]
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.instantiateAndPostProcessTestInstance(ClassBasedTestDescriptor.java:289) ~[junit-jupiter-engine-5.10.3.jar:5.10.3]
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$testInstancesProvider$4(ClassBasedTestDescriptor.java:279) ~[junit-jupiter-engine-5.10.3.jar:5.10.3]
at java.base/java.util.Optional.orElseGet(Optional.java:364) ~[na:na]
at org.junit.jupiter.engine.descriptor.ClassBasedTestDescriptor.lambda$testInstancesProvider$5(ClassBasedTestDescriptor.java:278) ~[junit-jupiter-engine-5.10.3.jar:5.10.3]
at org.junit.jupiter.engine.execution.TestInstancesProvider.getTestInstances(TestInstancesProvider.java:31) ~[junit-jupiter-engine-5.10.3.jar:5.10.3]
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$prepare$0(TestMethodTestDescriptor.java:106) ~[junit-jupiter-engine-5.10.3.jar:5.10.3]
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.prepare(TestMethodTestDescriptor.java:105) ~[junit-jupiter-engine-5.10.3.jar:5.10.3]
at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.prepare(TestMethodTestDescriptor.java:69) ~[junit-jupiter-engine-5.10.3.jar:5.10.3]
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$prepare$2(NodeTestTask.java:123) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.NodeTestTask.prepare(NodeTestTask.java:123) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:90) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at java.base/java.util.ArrayList.forEach(ArrayList.java:1511) ~[na:na]
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:41) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$6(NodeTestTask.java:155) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:141) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$9(NodeTestTask.java:139) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:138) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:95) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at java.base/java.util.ArrayList.forEach(ArrayList.java:1511) ~[na:na]
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:41) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$6(NodeTestTask.java:155) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:141) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:137) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$9(NodeTestTask.java:139) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:138) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:95) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:35) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:54) ~[junit-platform-engine-1.10.3.jar:1.10.3]
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:198) ~[junit-platform-launcher-1.10.3.jar:1.10.3]
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:169) ~[junit-platform-launcher-1.10.3.jar:1.10.3]
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:93) ~[junit-platform-launcher-1.10.3.jar:1.10.3]
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.lambda$execute$0(EngineExecutionOrchestrator.java:58) ~[junit-platform-launcher-1.10.3.jar:1.10.3]
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.withInterceptedStreams(EngineExecutionOrchestrator.java:141) ~[junit-platform-launcher-1.10.3.jar:1.10.3]
at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:57) ~[junit-platform-launcher-1.10.3.jar:1.10.3]
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:103) ~[junit-platform-launcher-1.10.3.jar:1.10.3]
at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:85) ~[junit-platform-launcher-1.10.3.jar:1.10.3]
at org.junit.platform.launcher.core.DelegatingLauncher.execute(DelegatingLauncher.java:47) ~[junit-platform-launcher-1.10.3.jar:1.10.3]
at org.junit.platform.launcher.core.SessionPerRequestLauncher.execute(SessionPerRequestLauncher.java:63) ~[junit-platform-launcher-1.10.3.jar:1.10.3]
at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:57) ~[junit5-rt.jar:na]
at com.intellij.rt.junit.IdeaTestRunner$Repeater$1.execute(IdeaTestRunner.java:38) ~[junit-rt.jar:na]
at com.intellij.rt.execution.junit.TestsRepeater.repeat(TestsRepeater.java:11) ~[idea_rt.jar:na]
at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:35) ~[junit-rt.jar:na]
at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:232) ~[junit-rt.jar:na]
at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:55) ~[junit-rt.jar:na]
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.itheima.dao.BookDao' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@javax.annotation.Resource(shareable=true, lookup="", name="", description="", authenticationType=CONTAINER, type=java.lang.Object.class, mappedName="")}
at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1880) ~[spring-beans-6.1.13.jar:6.1.13]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1406) ~[spring-beans-6.1.13.jar:6.1.13]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1353) ~[spring-beans-6.1.13.jar:6.1.13]
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.autowireResource(CommonAnnotationBeanPostProcessor.java:598) ~[spring-context-6.1.13.jar:6.1.13]
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.getResource(CommonAnnotationBeanPostProcessor.java:576) ~[spring-context-6.1.13.jar:6.1.13]
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor$LegacyResourceElement.getResourceToInject(CommonAnnotationBeanPostProcessor.java:789) ~[spring-context-6.1.13.jar:6.1.13]
at org.springframework.beans.factory.annotation.InjectionMetadata$InjectedElement.inject(InjectionMetadata.java:270) ~[spring-beans-6.1.13.jar:6.1.13]
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:145) ~[spring-beans-6.1.13.jar:6.1.13]
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessProperties(CommonAnnotationBeanPostProcessor.java:368) ~[spring-context-6.1.13.jar:6.1.13]
... 73 common frames omitted

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.itheima.test': Injection of resource dependencies failed

at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessProperties(CommonAnnotationBeanPostProcessor.java:371)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1439)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireBeanProperties(AbstractAutowireCapableBeanFactory.java:398)
at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:143)
at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:98)
at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:260)
at org.springframework.test.context.junit.jupiter.SpringExtension.postProcessTestInstance(SpringExtension.java:163)
at java.base/java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:197)
at java.base/java.util.stream.ReferencePipeline$2$1.accept(ReferencePipeline.java:179)
at java.base/java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1625)
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.StreamSpliterators$WrappingSpliterator.forEachRemaining(StreamSpliterators.java:310)
at java.base/java.util.stream.Streams$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:762)
at java.base/java.util.Optional.orElseGet(Optional.java:364)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
at java.base/java.util.ArrayList.forEach(ArrayList.java:1511)
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'com.itheima.dao.BookDao' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {@javax.annotation.Resource(shareable=true, lookup="", name="", description="", authenticationType=CONTAINER, type=java.lang.Object.class, mappedName="")}
at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1880)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1406)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1353)
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.autowireResource(CommonAnnotationBeanPostProcessor.java:598)
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.getResource(CommonAnnotationBeanPostProcessor.java:576)
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor$LegacyResourceElement.getResourceToInject(CommonAnnotationBeanPostProcessor.java:789)
at org.springframework.beans.factory.annotation.InjectionMetadata$InjectedElement.inject(InjectionMetadata.java:270)
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:145)
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessProperties(CommonAnnotationBeanPostProcessor.java:368)
... 18 more

2024-09-22T20:58:57.244+08:00 INFO 18108 --- [ionShutdownHook] com.alibaba.druid.pool.DruidDataSource : {dataSource-0} closing ...

Process finished with exit code -1

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一轮明月照丘壑 2024-09-22 21:23
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以下回复参考：皆我百晓生、券券喵儿等免费微信小程序作答:

从你提供的日志中，问题似乎出在Spring Boot在试图注入com.itheima.dao.BookDao这个bean时找不到它。这个问题通常是由于以下几个原因造成的：

缺少@Mapper注解：确保你的BookDao接口上有@Mapper注解。@Mapper注解会告诉MyBatis和Spring Boot这个接口是一个Mapper接口，应该被Spring Boot扫描并创建bean。

@Mapper public interface BookDao extends BaseMapper<Book> { }

Spring Boot未扫描到Mapper：如果BookDao在Spring Boot的扫描路径之外，那么Spring Boot将无法创建这个bean。确保BookDao在Spring Boot的扫描路径中，或者你可以在@MapperScan注解中明确指定包名。

@SpringBootTest @MapperScan("com.itheima.dao") public class test { // ... }

MyBatis Plus配置问题：确保MyBatis Plus的依赖已经正确添加到项目中，并且MyBatis Plus的配置是正确的。
检查pom.xml：确保所有的依赖都已经正确添加，并且版本之间没有冲突。
IDE的问题：有时IDE（如IntelliJ IDEA）可能会缓存旧的构建信息，导致项目无法正确构建。你可以尝试重启IDE，或者点击IDE的Build Project按钮，清除旧的构建缓存。

希望这些建议能帮助你解决问题。如果问题仍然存在，请提供更多关于你的项目配置和代码的信息，以便我能更准确地诊断问题。
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在IT行业中，Java是一种广泛应用的编程语言，尤其在后端开发领域占据主导地位。"27天成为Java大神"的计划旨在通过高效的学习路径，帮助初学者在短时间内掌握Java的核心概念和技术。以下是对这个学习过程中的关键知识...
Java 三目运算符判断两个对象是否为空 java
2015-08-28 06:08

回答 7 已采纳 ``` zyyzjymx!=null?(f1(zyyzjymx)):(mzzdjymx!=null?f1(mzzdjymx):null); ```
27天成就java大神练习题.rar
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"27天成就Java大神练习题"这个压缩包文件旨在通过一系列精心设计的练习题目，帮助学习者在27天内系统地提升Java编程技能，从基础到进阶，逐步掌握Java的核心概念和技术。在Java的学习过程中，通常会涉及到以下几个...
27天成为Java大神一个基于浏览器端
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标题中的“27天成为Java大神一个基于浏览器端”似乎是一个快速学习Java的课程或者教程，强调在较短时间内通过在线方式掌握Java编程。然而，描述中提到了"python编程"，这与标题中的Java有所冲突，可能是描述错误或者...
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有没有 java 大神啊！

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