Cause: java.lang.IllegalArgumentException: invalid comparison: java.util.ArrayList and java.lang.String

 翻譯過來就是

原因：java.lang.IllegalArgumentException：無效比較：java.util.ArrayList和java.lang.String

 

這個情況在list集合查找數據的sql中出的問題，在接受list的時候加了判斷  list!='' ,引起了集合與String類型的比較

<choose>
      <when test="names!= null and names.size!=''">
        and name in
        <foreach collection="names" item="name" index="index" open="(" close=")" separator=",">
          #{name}
        </foreach>
      </when>
      <otherwise>
        and name= ''
      </otherwise>
    </choose>

換成

<choose>
      <when test="names!= null and names.size>0">
        and name in
        <foreach collection="names" item="name" index="index" open="(" close=")" separator=",">
          #{name}
        </foreach>
      </when>
      <otherwise>
        and name= ''
      </otherwise>
    </choose>