【異常】：UnsatisfiedDependencyException: Error creating bean with name 'xxx[類]': Unsatisfied dependency expressed through field 'baseMapper';
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BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [com/baomidou/mybatisplus/autoconfigure/MybatisPlusAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.ibatis.session.SqlSessionFactory]: Factory method 'sqlSessionFactory' threw exception; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [D:\Project\xx\cyber\cyber-web\target\classes\mapper\ScanCyberMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. The XML location is 'file [D:\Project\xx\cyber\cyber-web\target\classes\mapper\ScanCyberMapper.xml]'. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'org.mybatis.caches.ehcache.LoggingEhcache'. Cause: java.lang.ClassNotFoundException: Cannot find class: org.mybatis.caches.ehcache.LoggingEhcache
Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled. 2020-04-18 16:46:43.334 [restartedMain] ERROR org.springframework.boot.SpringApplication.reportFailure(826) - Application run failed org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'zoneBO': Unsatisfied dependency expressed through field 'baseMapper'; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'zoneDAO' defined in file [D:\Project\yunda\cyber\cyber-web\target\classes\com\yd\cyber\web\dao\ZoneDAO.class]: Unsatisfied dependency expressed through bean property 'sqlSessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [com/baomidou/mybatisplus/autoconfigure/MybatisPlusAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.ibatis.session.SqlSessionFactory]: Factory method 'sqlSessionFactory' threw exception; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [D:\Project\yunda\cyber\cyber-web\target\classes\mapper\ScanCyberMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. The XML location is 'file [D:\Project\yunda\cyber\cyber-web\target\classes\mapper\ScanCyberMapper.xml]'. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'org.mybatis.caches.ehcache.LoggingEhcache'. Cause: java.lang.ClassNotFoundException: Cannot find class: org.mybatis.caches.ehcache.LoggingEhcache at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:643) at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:116) at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:399) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1422) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:594) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:517) at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:323) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:321) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:879) at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:878) at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550) 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.SpringApplication.run(SpringApplication.java:1226) at org.springframework.boot.SpringApplication.run(SpringApplication.java:1215) at com.yd.cyber.web.WebApplication.main(WebApplication.java:13) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'zoneDAO' defined in file [D:\Project\yunda\cyber\cyber-web\target\classes\com\yd\cyber\web\dao\ZoneDAO.class]: Unsatisfied dependency expressed through bean property 'sqlSessionFactory'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [com/baomidou/mybatisplus/autoconfigure/MybatisPlusAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.ibatis.session.SqlSessionFactory]: Factory method 'sqlSessionFactory' threw exception; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [D:\Project\yunda\cyber\cyber-web\target\classes\mapper\ScanCyberMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. The XML location is 'file [D:\Project\yunda\cyber\cyber-web\target\classes\mapper\ScanCyberMapper.xml]'. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'org.mybatis.caches.ehcache.LoggingEhcache'. Cause: java.lang.ClassNotFoundException: Cannot find class: org.mybatis.caches.ehcache.LoggingEhcache at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireByType(AbstractAutowireCapableBeanFactory.java:1526) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1406) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:594) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:517) at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:323) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:321) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1287) at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1207) at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:640) ... 24 common frames omitted Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in class path resource [com/baomidou/mybatisplus/autoconfigure/MybatisPlusAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.ibatis.session.SqlSessionFactory]: Factory method 'sqlSessionFactory' threw exception; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [D:\Project\yunda\cyber\cyber-web\target\classes\mapper\ScanCyberMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. The XML location is 'file [D:\Project\yunda\cyber\cyber-web\target\classes\mapper\ScanCyberMapper.xml]'. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'org.mybatis.caches.ehcache.LoggingEhcache'. Cause: java.lang.ClassNotFoundException: Cannot find class: org.mybatis.caches.ehcache.LoggingEhcache at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:656) at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:636) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1338) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1177) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:557) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:517) at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:323) at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:321) at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1287) at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1207) at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireByType(AbstractAutowireCapableBeanFactory.java:1511) ... 35 common frames omitted Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.apache.ibatis.session.SqlSessionFactory]: Factory method 'sqlSessionFactory' threw exception; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [D:\Project\yunda\cyber\cyber-web\target\classes\mapper\ScanCyberMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. The XML location is 'file [D:\Project\yunda\cyber\cyber-web\target\classes\mapper\ScanCyberMapper.xml]'. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'org.mybatis.caches.ehcache.LoggingEhcache'. Cause: java.lang.ClassNotFoundException: Cannot find class: org.mybatis.caches.ehcache.LoggingEhcache at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185) at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:651) ... 48 common frames omitted Caused by: org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [D:\Project\yunda\cyber\cyber-web\target\classes\mapper\ScanCyberMapper.xml]'; nested exception is org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. The XML location is 'file [D:\Project\yunda\cyber\cyber-web\target\classes\mapper\ScanCyberMapper.xml]'. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'org.mybatis.caches.ehcache.LoggingEhcache'. Cause: java.lang.ClassNotFoundException: Cannot find class: org.mybatis.caches.ehcache.LoggingEhcache at com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean.buildSqlSessionFactory(MybatisSqlSessionFactoryBean.java:595) at com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean.afterPropertiesSet(MybatisSqlSessionFactoryBean.java:430) at com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean.getObject(MybatisSqlSessionFactoryBean.java:628) at com.baomidou.mybatisplus.autoconfigure.MybatisPlusAutoConfiguration.sqlSessionFactory(MybatisPlusAutoConfiguration.java:214) at com.baomidou.mybatisplus.autoconfigure.MybatisPlusAutoConfiguration$$EnhancerBySpringCGLIB$$1952ec39.CGLIB$sqlSessionFactory$1(<generated>) at com.baomidou.mybatisplus.autoconfigure.MybatisPlusAutoConfiguration$$EnhancerBySpringCGLIB$$1952ec39$$FastClassBySpringCGLIB$$6017a70d.invoke(<generated>) at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:244) at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:363) at com.baomidou.mybatisplus.autoconfigure.MybatisPlusAutoConfiguration$$EnhancerBySpringCGLIB$$1952ec39.sqlSessionFactory(<generated>) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154) ... 49 common frames omitted Caused by: org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. The XML location is 'file [D:\Project\yunda\cyber\cyber-web\target\classes\mapper\ScanCyberMapper.xml]'. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'org.mybatis.caches.ehcache.LoggingEhcache'. Cause: java.lang.ClassNotFoundException: Cannot find class: org.mybatis.caches.ehcache.LoggingEhcache at org.apache.ibatis.builder.xml.XMLMapperBuilder.configurationElement(XMLMapperBuilder.java:122) at org.apache.ibatis.builder.xml.XMLMapperBuilder.parse(XMLMapperBuilder.java:94) at com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean.buildSqlSessionFactory(MybatisSqlSessionFactoryBean.java:593) ... 62 common frames omitted Caused by: org.apache.ibatis.type.TypeException: Could not resolve type alias 'org.mybatis.caches.ehcache.LoggingEhcache'. Cause: java.lang.ClassNotFoundException: Cannot find class: org.mybatis.caches.ehcache.LoggingEhcache at org.apache.ibatis.type.TypeAliasRegistry.resolveAlias(TypeAliasRegistry.java:120) at org.apache.ibatis.builder.xml.XMLMapperBuilder.cacheElement(XMLMapperBuilder.java:204) at org.apache.ibatis.builder.xml.XMLMapperBuilder.configurationElement(XMLMapperBuilder.java:116) ... 64 common frames omitted Caused by: java.lang.ClassNotFoundException: Cannot find class: org.mybatis.caches.ehcache.LoggingEhcache at org.apache.ibatis.io.ClassLoaderWrapper.classForName(ClassLoaderWrapper.java:200) at org.apache.ibatis.io.ClassLoaderWrapper.classForName(ClassLoaderWrapper.java:89) at org.apache.ibatis.io.Resources.classForName(Resources.java:261) at org.apache.ibatis.type.TypeAliasRegistry.resolveAlias(TypeAliasRegistry.java:116) ... 66 common frames omitted Disconnected from the target VM, address: '127.0.0.1:63325', transport: 'socket' Process finished with exit code 1
【原因】：我的原因是服務解析下面路徑時出現了問題，我的配置如下：同事這也卻沒有問題，心里真不是滋味。
1 mybatis-plus: 2 mapper-locations: classpath*:/mapper/*Mapper.xml
【解決方案一】：直接定義為全路徑
1 mybatis-plus: 2 mapper-locations: classpath:/src/main/resources/mapper/*Mapper.xml
【解決方案二】：Maven 項目，在 pom 文件的 resource 中指定 xml 路徑
1 <build> 2 <resources> 3 <resource> 4 <!-- xml放在java目錄下--> 5 <directory>src/main/java</directory> 6 <includes> 7 <include>**/*.xml</include> 8 </includes> 9 </resource> 10 <!--指定資源的位置（xml放在resources下，可以不用指定）--> 11 <resource> 12 <directory>src/main/resources</directory> 13 </resource> 14 </resources> 15 </build>
【解決方案三】：如果只是一個 mapper.xml 文件，直接指定也不會出現問題
1 mybatis-plus: 2 mapper-locations: /mapper/ZoneMapper.xml
【解決方案四】： 【目前使用的方案】因為加載 *Mapper.xml 文件的時候，里面配置了二級緩存【我生成的時候不小心生成的】，這個時候，就會出現上述的問題。而且二級緩存是有缺陷的，可能會導致獲取到的數據是舊數據，也就是關聯的數據沒有更新的問題。所以我們項目是關閉的，那么當我注釋掉二級緩存之后，這個問題也就解決了。
1 <!-- 開啟二級緩存 --> 2 <!-- <cache type="org.mybatis.caches.ehcache.LoggingEhcache"/>-->