mybatis 如何通过resultMap 返回long
作者：qq_16055765
这篇文章主要介绍了mybatis 如何通过resultMap 返回long的操作，具有很好的参考价值，希望对大家有所帮助。如有错误或未考虑完全的地方，望不吝赐教
mybatis resultMap 返回long
<resultMap id="ResultOfLong" type="java.lang.Long">
<result column="budget" property="budget" javaType="long"/>
</resultMap>
mybatis long 类型返回为null报异常
Mapper method 'com.mpn.dao.TWeatherMapper.avgWeatherTemperature attempted to return null from a method with a primitive return type (long).
<select id="avgWeatherTemperature" resultType="java.lang.Long" parameterType="java.lang.String" >
SELECT IFNULL(AVG(WeatherTemperature),0) AS OrderAverage FROM t_weather WHERE WeatherDate= #{date,jdbcType=VARCHAR};
</select>
<select id="sumWeatherRainfall" resultType="java.lang.Long" parameterType="java.lang.String" >
SELECT SUM(WeatherTemperature) AS OrderAverage FROM t_weather WHERE WeatherDate= #{date,jdbcType=VARCHAR};
</select>
<select id="avghumidity" resultType="java.lang.Long" parameterType="java.lang.String" >
SELECT IFNULL(AVG(WeatherHumidity),0) AS OrderAverage FROM t_weather WHERE WeatherDate= #{date,jdbcType=VARCHAR};
</select>
由于返回为空long中没有此类型所以抛异常，改为
<!-- 根据日期来进行计算平局值与 -->
<select id="avgWeatherTemperature" resultType="java.lang.Long" parameterType="java.lang.String" >
SELECT IFNULL(AVG(WeatherTemperature),0) AS OrderAverage FROM t_weather WHERE WeatherDate= #{date,jdbcType=VARCHAR};
</select>
<select id="sumWeatherRainfall" resultType="java.lang.Long" parameterType="java.lang.String" >
SELECT IFNULL(SUM(WeatherTemperature),0) AS OrderAverage FROM t_weather WHERE WeatherDate= #{date,jdbcType=VARCHAR};
</select>
<select id="avghumidity" resultType="java.lang.Long" parameterType="java.lang.String" >
SELECT IFNULL(AVG(WeatherHumidity),0) AS OrderAverage FROM t_weather WHERE WeatherDate= #{date,jdbcType=VARCHAR};
</select>
用IFNULL来进行判断！
以上为个人经验，希望能给大家一个参考，也希望大家多多支持脚本之家。