异常信息：
org.mybatis.spring.SqlSessionFactoryBean.buildSqlSessionFactory(SqlSessionFactoryBean.java:437) - Scanned package: 'com.***.entity' for aliases
org.mybatis.spring.SqlSessionFactoryBean.buildSqlSessionFactory(SqlSessionFactoryBean.java:534) - Property 'mapperLocations' was not specified or no matching resources found
org.mybatis.spring.mapper.MapperFactoryBean.checkDaoConfig(MapperFactoryBean.java:82) - Error while adding the mapper 'interface com.***.mapper.ImageMapper' to configuration.
java.lang.IllegalArgumentException: Mapped Statements collection already contains value for com.***.mapper.ImageMapper.getImage
at org.apache.ibatis.session.Configuration$StrictMap.put(Configuration.java:872) ~[mybatis-3.4.5.jar:3.4.5]
at org.apache.ibatis.session.Configuration$StrictMap.put(Configuration.java:844) ~[mybatis-3.4.5.jar:3.4.5]
at org.apache.ibatis.session.Configuration.addMappedStatement(Configuration.java:668) ~[mybatis-3.4.5.jar:3.4.5]
at org.apache.ibatis.builder.MapperBuilderAssistant.addMappedStatement(MapperBuilderAssistant.java:302) ~[mybatis-3.4.5.jar:3.4.5]
at org.apache.ibatis.builder.annotation.MapperAnnotationBuilder.parseStatement(MapperAnnotationBuilder.java:351) ~[mybatis-3.4.5.jar:3.4.5]
at org.apache.ibatis.builder.annotation.MapperAnnotationBuilder.parse(MapperAnnotationBuilder.java:134) ~[mybatis-3.4.5.jar:3.4.5]
at org.apache.ibatis.binding.MapperRegistry.addMapper(MapperRegistry.java:72) ~[mybatis-3.4.5.jar:3.4.5]
at org.apache.ibatis.session.Configuration.addMapper(Configuration.java:741) ~[mybatis-3.4.5.jar:3.4.5]
at org.mybatis.spring.mapper.MapperFactoryBean.checkDaoConfig(MapperFactoryBean.java:80) ~[mybatis-spring-1.3.1.jar:1.3.1]
at org.springframework.dao.support.DaoSupport.afterPropertiesSet(DaoSupport.java:44) ~[spring-tx-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1687) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1624) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:555) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:208) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1138) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1066) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:585) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:366) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1264) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:553) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:483) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:761) ~[spring-beans-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:867) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:543) ~[spring-context-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:122) ~[spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:693) ~[spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:360) ~[spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:303) ~[spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
at org.springframework.boot.web.support.SpringBootServletInitializer.run(SpringBootServletInitializer.java:154) ~[spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
at org.springframework.boot.web.support.SpringBootServletInitializer.createRootApplicationContext(SpringBootServletInitializer.java:134) ~[spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
at org.springframework.boot.web.support.SpringBootServletInitializer.onStartup(SpringBootServletInitializer.java:87) ~[spring-boot-1.5.10.RELEASE.jar:1.5.10.RELEASE]
at org.springframework.web.SpringServletContainerInitializer.onStartup(SpringServletContainerInitializer.java:169) ~[spring-web-4.3.14.RELEASE.jar:4.3.14.RELEASE]
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5311) ~[catalina.jar:8.0.50]
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145) ~[catalina.jar:8.0.50]
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:753) ~[catalina.jar:8.0.50]
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:729) ~[catalina.jar:8.0.50]
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717) ~[catalina.jar:8.0.50]
at org.apache.catalina.startup.HostConfig.manageApp(HostConfig.java:1730) ~[catalina.jar:8.0.50]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_161]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_161]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_161]
at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_161]
at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:300) ~[tomcat-coyote.jar:8.0.50]
at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819) ~[?:1.8.0_161]
at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801) ~[?:1.8.0_161]
at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:484) ~[catalina.jar:8.0.50]
at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:433) ~[catalina.jar:8.0.50]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_161]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_161]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_161]
at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_161]
at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:300) ~[tomcat-coyote.jar:8.0.50]
at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819) ~[?:1.8.0_161]
at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801) ~[?:1.8.0_161]
at javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:1468) ~[?:1.8.0_161]
at javax.management.remote.rmi.RMIConnectionImpl.access$300(RMIConnectionImpl.java:76) ~[?:1.8.0_161]
at javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(RMIConnectionImpl.java:1309) ~[?:1.8.0_161]
at javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(RMIConnectionImpl.java:1401) ~[?:1.8.0_161]
at javax.management.remote.rmi.RMIConnectionImpl.invoke(RMIConnectionImpl.java:829) ~[?:1.8.0_161]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[?:1.8.0_161]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[?:1.8.0_161]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_161]
at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_161]
at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:361) ~[?:1.8.0_161]
at sun.rmi.transport.Transport$1.run(Transport.java:200) ~[?:1.8.0_161]
at sun.rmi.transport.Transport$1.run(Transport.java:197) ~[?:1.8.0_161]
at java.security.AccessController.doPrivileged(Native Method) ~[?:1.8.0_161]
at sun.rmi.transport.Transport.serviceCall(Transport.java:196) ~[?:1.8.0_161]
at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:568) ~[?:1.8.0_161]
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:826) ~[?:1.8.0_161]
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.lambda$run$0(TCPTransport.java:683) ~[?:1.8.0_161]
at java.security.AccessController.doPrivileged(Native Method) ~[?:1.8.0_161]
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:682) [?:1.8.0_161]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [?:1.8.0_161]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [?:1.8.0_161]
at java.lang.Thread.run(Thread.java:748) [?:1.8.0_161]
这就是错误的根源：
解决方案其实很简单(就是因为mapper 里面出现了重载方法，mybatis 很坑，mapper 接口里面不能出现重载方法的情况)，可是百度了很久，根本就没有解决方案。