Type handler was null on parameter mapping or property ‘__frch_xxx_0’
可知是mapper.xml写错，因为使用foreach语句时，两个foreach标签中间的参数写错了
<select id=" get" parameterType="entity" resultMap="java.util.List"> select id, name from t where id in <foreach collection="list" item="param" open="(" close=")" separator=","> #{param.id} 这里直接用#{id}或#{param}，就会报错 </foreach> </select>
