需求:根據商品id或者itemName查詢商品詳情

一個定義了若干個引數的介面，當客戶端發起請求而攜帶的引數個數不確定時，為了能夠正常響應，需要對介面做一個適配處理。

1.controller層開發

@Controller
@RequestMapping("/items")
public class ItemsController {
	@Autowired
	private ItemsServiceImpl itemsService;
	
	//根據商品id或者itemName查詢商品詳情
	@RequestMapping(value="/getItemByItemIdAndItemName",method = RequestMethod.POST)
	@ResponseBody
	public WebResult getItemByItemIdAndItemName(@RequestBody String itemsCustom)throws Exception{
		WebResult result = WebResultHelper.newResult();
		ItemsCustom items = JSON.parseObject(itemsCustom, ItemsCustom.class);
		Items item = itemsService.getItemByItemIdAndItemName(items);
		if(item == null){
		    return  WebResultHelper.newErrorResult("沒有查詢到資料！");
		}
		result.put("data",item);
		return result;
	}
}
 

2.service層開發

//ItemsService
public interface ItemsService {
	Items getItemByItemIdAndItemName(ItemsCustom itemsCustom) throws Exception;
}

//ItemsServiceImpl
@Service
public class ItemsServiceImpl implements ItemsService {
	@Autowired
	private ItemsMapperCustom itemsMapperCustom;
	
	@Override
	public Items getItemByItemIdAndItemName(ItemsCustom itemsCustom) throws Exception {
	    return itemsMapperCustom.getItemByItemIdAndItemName(itemsCustom);
	}
}
 

3.dao層開發

//mapper介面
public interface ItemsMapperCustom {
	Items getItemByItemIdAndItemName(ItemsCustom itemsCustom) throws Exception;
}

//sql對映檔案
<mapper namespace="com.steven.ssm.mapper.ItemsMapperCustom" >
   <select id="getItemByItemIdAndItemName" parameterType="itemsCustom" resultMap="queryItems">
        select * from items
        <where>
            <if test="itemId!=null and itemId!=''">
              and item_id = #{itemId}
            </if>
            <if test="itemName!=null and itemName!=''">
                and item_name = #{itemName}
            </if>
        </where>
    </select>
</mapper>
 

//pojo類
public class Items {
    private Integer itemId;
    private String itemName;
    private Long itemPrice;
    private String itemDetail;
    private Date itemCreateDate;
    //get和set方法......
}

4.測試
如截圖所示，組合選擇itemId和itemName作為請求引數都可以查詢到相應的資料。