On MyBatis Dynamic If statement query error problem and solution

Similar to an error in MyBatis

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

There are 2 solutions without removing the IF label
Workaround 1
In the. xml file, replace the username with _parameter, which applies to a single parameter, as follows

    <select id= "Selectuserbyname" parametertype= "String" resultmap= "user" >
        select
        <include refid= " Querycolumns "/> from
        z_user,z_basic
        <where>
            <if test=" Username! = null ">
                username Like CONCAT ('% ', #{username}, '% ')
            </if>
        </where>
    </select>

    <select id= "Selectuserbyname" parametertype= "String" resultmap= "user" >
        select
        <include refid= " Querycolumns "/> from
        z_user,z_basic
        <where>
            <if test=" _parameter! = null ">
                username Like CONCAT ('% ', #{username}, '% ')
            </if>
        </where>
    </select>
    <select id= " Selectalluser "resultmap=" user ">
        select
        <include refid=" Querycolumns "/>
        , Text,password,z _basic.id from
        z_user,z_basic
        where
        z_user.id=z_basic.z_basic.id
    </select>

Workaround 2
DECLARE @param ("username") in the Mapper interface, as follows

List<user> Selectuserbyname (@Param ("username") String username);

I hope the above two methods are useful to everyone