mybatis "There is no getter for property named 'xx' in 'class java.lang.String"问题

用mybatis查询时，传入一个字符串参数，且进行判断时，会报There is no getter for property named 'xx' in 'class java.lang.String的错误．

例：

<select id="SelectFeedback" parameterType="String" resultType="com.fjnu.domain.CoachStudent">
SELECT a.id, c.coa_name, c.stu_name, c.cou_name, c.station, c.grade, c.clazz, c.weekday, a.time AS date, a.lateTime, a.remark, a.rate, a.type
FROM t_feedback a, c_s_detail b, Coach_Student c WHERE 1 = 1
AND a.cs_id = b.id
AND b.coa_stu_id = c.id
<if test="station != null and station!= ''">
AND c.station = #{station}
</if>
</select>

传入　station　参数，但是会报错

应改为

<select id="SelectFeedback" parameterType="String" resultType="com.fjnu.domain.CoachStudent">
SELECT a.id, c.coa_name, c.stu_name, c.cou_name, c.station, c.grade, c.clazz, c.weekday, a.time AS date, a.lateTime, a.remark, a.rate, a.type
FROM t_feedback a, c_s_detail b, Coach_Student c WHERE 1 = 1
AND a.cs_id = b.id
AND b.coa_stu_id = c.id
<if test="_parameter != null and _parameter != ''">
AND c.station = #{_parameter}
</if>
</select>

把参数替换为_parameter

原因：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。