我使用Spring和MyBatis作为学习MyBatis框架的演示项目。我正在反复上课，没有发现异常。

Question

我得到的类没有发现异常反复。

Error parsing SQL Mapper Configuration. Cause: org.apache.ibatis.builder.BuilderException: Error registering typeAlias for 'Emp'. Cause: java.lang.ClassNotFoundException: Cannot find class: classpath*:com.attinad.model.Employee

下面给出了我的myBati-config.xml文件：

    <?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
    PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
    "http://mybatis.org/dtd/mybatis-3-config.dtd">

 <configuration>
  <typeAliases><typeAlias type="classpath*:com.attinad.model.Employee" alias="Emp"/></typeAliases>

 <mappers>
        <mapper resource="classpath:com/attinad/mappers/EmployeeMapper.xml" />
 </mappers>

</configuration>

和ds-config.xml：

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN 2.0//EN" "http://www.springframework.org/dtd/spring-beans-2.0.dtd">
 <beans >
    <bean id="dataSource" class="org.springframework.jndi.JndiObjectFactoryBean">
        <property name="jndiName" value="java:comp/env/jdbc/corpds"/>
    </bean>
    <bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <property name="dataSource" ref="dataSource" />
     </bean>

            <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
            <property name="dataSource" ref="dataSource" />             
            <property name="typeAliasesPackage" value="classpath*:com/attinad/model/*"/>        
            <property name="configLocation" value="classpath:myBatis-config.xml" />
            <property name="mapperLocations" value="classpath*:com/attinad/mappers/*.xml" />
     </bean>

</beans>

我的映射文件EmployeeMapper.xml：

<?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="com.attinad.dao.EmployeeMapperInterface">
<resultMap type="Emp" id="EmpResult">
    <id property="id" column="id"/>
    <result property="createdAt" column="createdAt"/>
    <result property="department" column="department"/>
    <result property="displayName" column="displayName"/>
    <result property="emailId" column="emailId"/>
    <result property="isEnable" column="isEnable"/>
    <result property="name" column="name"/>
    <result property="updatedAt" column="updatedAt"/>
</resultMap>

<select id="getEmployeeWithId" parameterType="Long" resultMap="EmpResult"> 
        select *  from
        employees where
        id=#{empId}

    </select>
</mapper>

这是我的刀课：

package com.attinad.dao;

import java.util.*;
import com.attinad.model.*;
public interface EmployeeMapperInterface extends BaseMapperInterface{
    public List<Employee> getEmployeeWithId(long id);
    public int insertEmployee(Employee e);
    public int updateEmployee(Employee e);
    public void deleteEmployee(int id);

}

我的服务班：

package com.attinad.service;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.attinad.dao.EmployeeMapperInterface;
import com.attinad.model.Employee;


    @Service
    public class EmployeeService implements EmployeeBaseService{

        @Autowired
        EmployeeMapperInterface employeeMapper;

         @Override    
         public Employee getEmployeeById(long empId){

            List<Employee> empList = employeeMapper.getEmployeeWithId(empId);
            if(empList != null && empList.size()>0){
                //System.out.println("List accumulated");
                System.out.println(empList);
                return (Employee) empList.get(0);

            }
            return null;

        }
}

Eclipse构建路径:src/main/ Java包含在Java构建路径中，我的包在这个类路径下。

请帮我解决这个错误。我不知道真正的原因。当我移除resultMap并使它成为ResultType="hashMap“时，它就起作用了。但是现在，如果我尝试这样做，我将为其他类获得ClassNotFound。

Answer 1

错误消息非常明确地表明类加载程序试图加载名为classpath*:com.attinad.model.Employee的类。

typeAliases配置应该如下所示：

<typeAliases><typeAlias type="com.attinad.model.Employee" alias="Emp"/></typeAliases>

注意事项：classpath*:被移除。

sqlSessionFactory bean配置也存在同样的问题。typeAliasPackage应该如下所示：

<property name="typeAliasesPackage" value="com.attinad.model"/>