org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.mybatis.

mybatis整合spring，使用org.mybatis.spring.mapper.MapperScannerConfigurer扫描出现问题

配置文件:

这里贴出完整的异常信息

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'org.mybatis.spring.mapper.MapperScannerConfigurer#0' defined in class path resource [spring_mvc.xml]: Initialization of bean failed; nested exception is org.springframework.beans.ConversionNotSupportedException: Failed to convert property value of type 'org.apache.ibatis.session.defaults.DefaultSqlSessionFactory' to required type 'java.lang.String' for property 'sqlSessionFactoryBeanName'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [org.apache.ibatis.session.defaults.DefaultSqlSessionFactory] to required type [java.lang.String] for property 'sqlSessionFactoryBeanName': no matching editors or conversion strategy found
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:547)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
at org.springframework.context.support.PostProcessorRegistrationDelegate.invokeBeanFactoryPostProcessors(PostProcessorRegistrationDelegate.java:116)
at org.springframework.context.support.AbstractApplicationContext.invokeBeanFactoryPostProcessors(AbstractApplicationContext.java:606)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:462)
at org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:663)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:629)
at org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:677)
at org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:548)
at org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:489)
at org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136)
at javax.servlet.GenericServlet.init(GenericServlet.java:158)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1183)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1099)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:989)
at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4931)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5241)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1419)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1409)
at java.util.concurrent.FutureTask.run(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
Caused by: org.springframework.beans.ConversionNotSupportedException: Failed to convert property value of type 'org.apache.ibatis.session.defaults.DefaultSqlSessionFactory' to required type 'java.lang.String' for property 'sqlSessionFactoryBeanName'; nested exception is java.lang.IllegalStateException: Cannot convert value of type [org.apache.ibatis.session.defaults.DefaultSqlSessionFactory] to required type [java.lang.String] for property 'sqlSessionFactoryBeanName': no matching editors or conversion strategy found
at org.springframework.beans.BeanWrapperImpl.convertIfNecessary(BeanWrapperImpl.java:476)
at org.springframework.beans.BeanWrapperImpl.convertForProperty(BeanWrapperImpl.java:512)
at org.springframework.beans.BeanWrapperImpl.convertForProperty(BeanWrapperImpl.java:506)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.convertForProperty(AbstractAutowireCapableBeanFactory.java:1523)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1482)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1222)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
... 27 more
Caused by: java.lang.IllegalStateException: Cannot convert value of type [org.apache.ibatis.session.defaults.DefaultSqlSessionFactory] to required type [java.lang.String] for property 'sqlSessionFactoryBeanName': no matching editors or conversion strategy found
at org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:287)
at org.springframework.beans.BeanWrapperImpl.convertIfNecessary(BeanWrapperImpl.java:461)
... 33 more

分析原因：

因为MapperScannerConigurer实际是在解析加载bean定义阶段的，这个时候要是设置sqlSessionFactory的话，会导致提前初始化一些类，这个时候，PropertyPlaceholderConfigurer还没来得及替换定义中的变量，导致把表达式当作字符串复制了

解决办法：

第一种方式：

修改

property name="sqlSessionFactory" ref="sqlSessionFactory"

为

`property name="sqlSessionFactoryBeanName"` value="sqlSessionFactory"

原理：使用

sqlSessionFactoryBeanName

注入，不会立即初始化

sqlSessionFactory

, 所以不会引发提前初始化问题。

第二种：直接删掉

注意：在没有配置这一行时，必须配置一个以

sqlSessionFactory

命名的

org.mybatis.spring.SqlSessionFactoryBean

。