以接口的方式编程 问题解析

异常：

Exception in thread "main" org.apache.ibatis.binding.BindingException: Type interface com.yihaomen.mybatis.inter.IUserOperation is not known to the MapperRegistry.
 at org.apache.ibatis.binding.MapperRegistry.getMapper(MapperRegistry.java:42)
 at org.apache.ibatis.session.Configuration.getMapper(Configuration.java:655)
 at org.apache.ibatis.session.defaults.DefaultSqlSession.getMapper(DefaultSqlSession.java:218)
 at com.yihaomen.test.Test.main(Test.java:33)

 

缘由：User.xml 文件中 mapper中：错误以下红色字体为错误命名空间，接口编程中应对应接口所在路径 ，绿色为正确配置。

<--------?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">
<--------!--namespace="com.yihaomen.mybatis.inter.IUserOperation"  -->
<--------mapper namespace="com.yihaomen.mybatis.models.UserMapper" >
    <--------select id="selectUserByID" parameterType="int" resultType="User">
        select * from `user` where id = #{id}
    <--------/select>
<--------/mapper>

注意：增长，更改，删除的时候要调用session.commit()，这样才会真正对数据库进行操做，不然是没有提交的。