MyBatis There is no getter for property named 'xxx' in 'class java.lang.String'

1. Code

1.1 mapper xml

 <select id="getItems" parameterType="string" resultMap="itemResult">...</select>

1.2 mapper interface

 public interface OrderDao {
     public List<Item> getItems(String orderIds);
 }

2. Issue

 There is no getter for property named 'orderIds' in 'class java.lang.String'

3. Solution1

 import org.apache.ibatis.annotations.Param;

 public interface OrderDao {
     public List<Item> getItems(@Param("orderIds") String orderIds);
 }

4.Solution2

一、发现问题
<select id="queryStudentByNum" resultType="student" parameterType="string">  
select num,name,phone from student  
<where> 
<if test = " num!=null and num!='' ">
AND num = #{num}
</if>
</where>
</select> 
Mybatis查询传入一个字符串传参数，报There is no getter for property named 'num' in 'class java.lang.String'。


二、解决问题
<select id="queryStudentByNum" resultType="student" parameterType="string">  
select num,name,phone from student  
<where> 
<if test = " _parameter!=null and_parameter!='' ">
AND num = #{_parameter}
</if>
</where>
</select>
无论参数名，都要改成"_parameter"。


三、原因分析
Mybatis默认采用ONGL解析参数，所以会自动采用对象树的形式取string.num值，引起报错。也可以public List methodName(@Param(value="num") String num)的方法说明参数值

参考博客：
http://blog.sina.com.cn/s/blog_86e49b8f010191hw.html
http://txin0814.iteye.com/blog/1533645

Reference: 

[1] http://stackoverflow.com/questions/19848861/mybatis-dynamic-sql-using-longs