mybatis resultMap 返回long
|
1 2 3 |
< 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).
|
1 2 3 4 5 6 7 8 9 10 11 |
< 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
|
1 2 3 4 5 6 7 8 9 10 11 12 |
<!-- 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。
原文链接：https://blog.csdn.net/qq_16055765/article/details/79665579
查看更多关于mybatis 如何通过resultMap 返回long的详细内容...