Caused by: org.apache.ibatis.type.TypeException: Could not resolve type alias 'Student'

1、错误描述

 Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'sqlSessionFactory' defined in URL [file:/F:/Tomcat/apache-tomcat-7.0.69/webapps/cmp/WEB-INF/classes/applicationContext.xml]: Invocation of init method failed; nested exception is org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [F:Tomcatapache-tomcat-7.0.69webappscmpWEB-INFclassesmybatissysStudentMapper.xml]'; nested exception is java.lang.RuntimeException: Error parsing Mapper XML. Cause: org.apache.ibatis.builder.BuilderException: Error resolving class. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'Student'.  Cause: java.lang.ClassNotFoundException: Cannot find class: Student
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1553)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:539)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
	at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304)
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300)
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
	at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:328)
	... 92 more
Caused by: org.springframework.core.NestedIOException: Failed to parse mapping resource: 'file [F:Tomcatapache-tomcat-7.0.69webappscmpWEB-INFclassesmybatissysStudentMapper.xml]'; nested exception is java.lang.RuntimeException: Error parsing Mapper XML. Cause: org.apache.ibatis.builder.BuilderException: Error resolving class. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'Student'.  Cause: java.lang.ClassNotFoundException: Cannot find class: Student
	at org.mybatis.spring.SqlSessionFactoryBean.buildSqlSessionFactory(SqlSessionFactoryBean.java:462)
	at org.mybatis.spring.SqlSessionFactoryBean.afterPropertiesSet(SqlSessionFactoryBean.java:336)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1612)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1549)
	... 99 more
Caused by: java.lang.RuntimeException: Error parsing Mapper XML. Cause: org.apache.ibatis.builder.BuilderException: Error resolving class. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'Student'.  Cause: java.lang.ClassNotFoundException: Cannot fi
nd class: Student
	at org.apache.ibatis.builder.xml.XMLMapperBuilder.configurationElement(XMLMapperBuilder.java:113)
	at org.apache.ibatis.builder.xml.XMLMapperBuilder.parse(XMLMapperBuilder.java:88)
	at org.mybatis.spring.SqlSessionFactoryBean.buildSqlSessionFactory(SqlSessionFactoryBean.java:460)
	... 102 more
Caused by: org.apache.ibatis.builder.BuilderException: Error resolving class. Cause: org.apache.ibatis.type.TypeException: Could not resolve type alias 'Student'.  Cause: java.lang.ClassNotFoundException: Cannot find class: Student
	at org.apache.ibatis.builder.BaseBuilder.resolveClass(BaseBuilder.java:100)
	at org.apache.ibatis.builder.xml.XMLMapperBuilder.resultMapElement(XMLMapperBuilder.java:257)
	at org.apache.ibatis.builder.xml.XMLMapperBuilder.resultMapElement(XMLMapperBuilder.java:244)
	at org.apache.ibatis.builder.xml.XMLMapperBuilder.resultMapElements(XMLMapperBuilder.java:236)
	at org.apache.ibatis.builder.xml.XMLMapperBuilder.configurationElement(XMLMapperBuilder.java:109)
	... 104 more
Caused by: org.apache.ibatis.type.TypeException: Could not resolve type alias 'Student'.  Cause: java.lang.ClassNotFoundException: Cannot find class: Student
	at org.apache.ibatis.type.TypeAliasRegistry.resolveAlias(TypeAliasRegistry.java:113)
	at org.apache.ibatis.builder.BaseBuilder.resolveAlias(BaseBuilder.java:127)
	at org.apache.ibatis.builder.BaseBuilder.resolveClass(BaseBuilder.java:98)
	... 108 more
Caused by: java.lang.ClassNotFoundException: Cannot find class: Student
	at org.apache.ibatis.io.ClassLoaderWrapper.classForName(ClassLoaderWrapper.java:188)
	at org.apache.ibatis.io.ClassLoaderWrapper.classForName(ClassLoaderWrapper.java:87)
	at org.apache.ibatis.io.Resources.classForName(Resources.java:254)
	at org.apache.ibatis.type.TypeAliasRegistry.resolveAlias(TypeAliasRegistry.java:109)
	... 110 more

2、错误原因

<resultMap type="Student" id="StudentMap">  
       <result column="STU_NO" property="stuNo" />  
       <result column="STU_NAME" property="stuName" />  
       <result column="STU_SEX" property="stuSex" />  
       <result column="STU_AGE" property="stuAge" />  
</resultMap>

      在Mybatis配置文件中用到实体类Student，但是没有配置或引入这个实体类，导致报错

3、解决办法

     在mybatis-config.xml添加

<typeAlias type="com.cmp.entity.Student" alias="Student"/>