Java写一个查询接口（从Controller到Mapper）

1.Controller 中：

    @ApiOperation("zzh查询")
    @GetMapping("/query")
    public ApiResult<List<EmerResourceVO>> queryVo(EmerResourceParam param) {
        PageParam<EmerResourceVO, EmerResourceParam> page = new PageParam<>(param);
//        page.setDefaultOrder("p.sorts  asc");
        // 使用关联查询
        return success(emerResourceService.selectListVO(param));
    }

2.Service中：

 List<EmerResourceVO> selectListVO(EmerResourceParam param);

3.Sercicelmpl中：

  @Override
    public List<EmerResourceVO> selectListVO(EmerResourceParam param) {
        return baseMapper.selectListVO(param);
    }

4.Mapper中：

List<EmerResourceVO> selectListVO(@Param("param") EmerResourceParam param);

5.Mapper.xml中：

 <select id="selectListVO" resultType="com.egao.community.vo.EmerResourceVO">
        SELECT a.*,
               b.dict_data_name as dictDataName
        FROM (<include refid="selectSql"></include>) a
        LEFT JOIN sys_dictionary_data b ON a.resource_type = b.dict_data_id
        <where>
        <if test="param.emerResourceId != null">
            AND a.emer_resource_id = #{param.emerResourceId}
        </if>
        <if test="param.emerResourceCode != null">
            AND a.emer_resource_code LIKE CONCAT('%', #{param.emerResourceCode}, '%')
        </if>
        <if test="param.emerResourceName != null">
            AND a.emer_resource_name LIKE CONCAT('%', #{param.emerResourceName}, '%')
        </if>
        <if test="param.emerResourceQuantity != null">
            AND a.emer_resource_quantity = #{param.emerResourceQuantity}
        </if>
            <if test="param.usable != null">
                AND a.usable = #{param.usable}
            </if>
        </where>
    </select>