spring+mybatis报错：Caused by: org.springframework.beans.factory.BeanCreationException: Error creating

1、报错信息

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'calSqlSessionFactory' defined in class path resource [spring-cal-dao.xml]: Invocation of init method failed; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [D:\workspace\eclipse-workspace\cal-task\cal-task-dao\target\classes\mybatis\SSubjectBlockItem.xml]'; nested exception is java.lang.RuntimeException: Error parsing Mapper XML. Cause: java.lang.IllegalArgumentException: Mapped Statements collection already contains value for SBlockItem.queryItemsByModuleId
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1583)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:553)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:482)
at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:306)
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:302)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:197)
at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:351)
... 28 more

2、报错原因：

java.lang.IllegalArgumentException: Mapped Statements collection already contains value for SBlockItem.queryItemsByModuleId

3、解决方案：

出现这个错误的原因是mybatis的映射文件（.xml）中存在相同命名空间的namespace，重命名这个namespace（SSubjectBlockItem）重启即可

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"  "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="SSubjectBlockItem">  <!--修改SSubjectBlockItem-->

</mapper>