在学习mybatis,曾报错:
org.apache.ibatis.exceptions.PersistenceException
 Error building SqlSession.
### The error may exist in mappers/StudentMapper.xml
### Cause: org.apache.ibatis.builder.BuilderException: Error parsing SQL Mapper Configuration. Cause: org.apache.ibatis.builder.BuilderException: Error parsing Mapper XML. The XML location is 'mappers/StudentMapper.xml'. Cause: org.apache.ibatis.builder.BuilderException: Parsing error was found in mapping #{}.  Check syntax #{property|(expression), var1=value1, var2=value2, ...} 
 

在一点点查询代码语法是否出错无解后,无疑中看到一篇文章评论中写道,于是就把问题解决了

原映射文件代码为
<?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.tian.dao.StudentDAO">
<insert id="insertStudent" parameterType="com.tian.pojo.Student">
    -- id里面为DAO中的方法名
    -- #{}中间的为Student类中的参数,因为insertStudent传参有Student类所以直接可以写Student中的属性
  insert into tb_students(stu_num,stu_name,stu_gender,stu_age)
    values(#{stuNum},#{stuName},#{stuGender},#{stuAge})
</insert>
<!--    <delete id="deleteStudent">-->
<!--        delete from tb_students where stu_num=#{stuNum}-->
<!--    </delete>-->
</mapper> 
把注释从 -- 修改为 <!---->,就可以了
现代码为:
<?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.tian.dao.StudentDAO">
<insert id="insertStudent" parameterType="com.tian.pojo.Student">
    <!--
     id里面为DAO中的方法名
     #{}中间的为Student类中的参数,因为insertStudent传参有Student类所以直接可以写Student中的属性
    -->
    <!--   -->
  insert into tb_students(stu_num,stu_name,stu_gender,stu_age)
    values(#{stuNum},#{stuName},#{stuGender},#{stuAge})
</insert>
<!--    <delete id="deleteStudent">-->
<!--        delete from tb_students where stu_num=#{stuNum}-->
<!--    </delete>-->
</mapper> 

另外我还有了个发现,在映射文件中使用 -- 或者 /**/ xml是不会解析为注释的,只有
<!-- -->是不会被解析里面的内容的











