Mybatis异常There is no getter for property named 'XXX' in 'class java.lang.String

Mybatis异常There is no getter for property named ‘XXX’ in ‘class java.lang.String’

问题：当入参为 string类型时 (包括java.lang.String.)

<select id="getBookingCount" resultType="int" parameterType="string">

select count(*) from TB_EMPC_BOOKING_ORDER T

where (t.state = '1' or t.state = '2')

and t.appointmenttime = #{state}

</select>

解决方法一:把#{xxx}修改为 #{_parameter} 即可

<select id="getBookingCount" resultType="int" parameterType="string">

select count(*) from TB_EMPC_BOOKING_ORDER T

where (t.state = '1' or t.state = '2')

and t.appointmenttime = #{_parameter}

</select>

解决方法二:可以在方法中提前定义:

public int  methodName(@Param(value="state") String state ){

　　...

}

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.xxx 值，如果没在在方法中定义,则会抛异常报错。