此处不允许使用特性namespace

1.DOCTYPE 后面改成 mapper

2.PUBLIC一行中的Config改为Mapper

3.将下一行config变为小写的mapper

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.wode.mybatisde.mapper.EmpMapper"><select id=""></select>
</mapper>