if else判断格式

<choose>
　　<when test="">
　　　　//...
　　</when>
　　<otherwise>
　　　　//...
　　</otherwise>
</choose>

<choose>
            <when test="orderType=1">
                order by aci.register_time desc
            </when>
            <when test="orderType=2">
                order by aci.register_time asc
            </when>
            <when test="orderType=3">
                order by aci.register_capital_qxx desc
            </when>
            <when test="orderType=3">
                order by aci.register_capital_qxx asc
            </when>
            <otherwise>
                order by aci.id desc
            </otherwise>
        </choose>