在Mybatis中选择整数列表作为另一个结果映射中的集合

Question

class Mapping {
private String name;
private List<Integer> ids;
}

Mybatis如下：

<resultMap id="mapping" type="some.package.Mapping">
        <result property="name" column="name"/>
        <collection property="ids" column="id" javaType="java.util.List" ofType="java.lang.Integer" />
</resultMap>

<select id="getMapping" resultMap="mapping">
        SELECT name, id
        FROM mapping
    </select>

这个代码对我不适用。我错过了什么？

Answer 1

如果有像List这样的自定义对象，那么我们如何为它编写XML conf-

public class AllEmployee{
List<Employee> employees;
}

public class Employee {
    String globalId;
    int empId;
    String name;
    List<Department> departmentList;
    }
    
public class Department {
    int empId;
    int depId;
    String depValue;
}

MyBatis xml配置-

<resultMap id="empMapper" type="Employee">
        <id property="globalId" column="globalId" />
        <result property="empId" column="empId" />
        <result property="name" column="name" />
        <collection property="departmentList" javaType="ArrayList" ofType="Department"/>
        <id property="empId" column="empId" />
        <result property="depId" column="depId" />
        <result property="depValue" column="depValue" />
        </collection>
</resultMap>

<select id="retriveAllEmployees" resultMap="empMapper">
        SELECT ee.empId, ee.name, dt.depId, dt.depValue FROM employee ee
        INNER JOIN department dt on dt.empId = ee.empId
        <where>
            globalId IN
            <foreach collection="globalIdList" item="globalId" separator=", " open="(" close=")">
                #{globalId}
            </foreach>
        </where>
    </select>

正确的json输出应该是-

{
  "employees": [
    {
      "empId": 1,
      "name": "alton",
      "departmentList": [
        {
          "depId": 2,
          "depValue": "fire"
        },
        {
          "depId": 4,
          "depValue": "ice"
        }
      ]
    }
  ]
}

{
  "employees": [
    {
      "empId": 1,
      "name": "alton",
      "departmentList": [
        {
          "depId": 2,
          "depValue": "fire"
        }
      ]
    },
    {
      "empId": 1,
      "name": "alton",
      "departmentList": [
        {
          "depId": 4,
          "depValue": "ice"
        }
      ]
    }
  ]
}