目录

• Mybatis条件if test使用枚举值
• 1.正确
• 2.错误
• Mybatis里使用枚举Enum判断
• TestTypeEnum定义如下

Mybatis条件if test使用枚举值

1.正确

package com.weather.weatherexpert.common.utils;
/**
 * <p>Title: </p>
 * <p>Description: </p>
 *
 * @Author 
 * @CreateTime 
 */
public enum City {
    XINZHOU(100002,"忻州"),
    DATONG(100003,"大同"),
    TAIYUAN(100001,"太原");
 
    private final Integer code;
    private final String name;
 
    City(Integer value, String desc) {
        this.code = value;
        this.name = desc;
    }
 
    public Integer getCode() {
        return code;
    }
 
    public String getName() {
        return name;
    }
}

xml：

<!--<if test="cityName == @com.weather.weatherexpert.common.utils.City.XINZHOU@getName">&lt;!&ndash;wrong,java.lang.ClassNotFoundException: Unable to resolve class: com.weather.weatherexpert.common.utils.City.XINZHOU&ndash;&gt;-->
<!--<if test="cityName == @com.weather.weatherexpert.common.utils.City@XINZHOU@getName">&lt;!&ndash;wrong,[org.apache.ibatis.ognl.ParseException: Encountered " "@" "@ "" at line 1, column 65.&ndash;&gt;-->
<if test="cityName == @com.weather.weatherexpert.common.utils.City@XINZHOU.getName"><!--right-->
	area_table
</if>
 
where 1=1
<if test="cityName == @com.weather.weatherexpert.common.utils.City@XINZHOU.getName"><!--right-->
	and city_name=#{cityName}
</if>	

2.错误

package com.weather.weatherexpert.common.utils;
/**
 * <p>Title: </p>
 * <p>Description: </p>
 *
 * @Author
 * @CreateTime
 */
public class CityClass {
    public static enum CityEnum {
 
        XINZHOU(100002, "忻州"),
        DATONG(100003, "大同"),
        TAIYUAN(100001, "太原");
 
        private final Integer code;
        private final String name;
 
        CityEnum(Integer value, String desc) {
            this.code = value;
            this.name = desc;
        }
 
        public Integer getCode() {
            return code;
        }
 
        public String getName() {
            return name;
        }
    }
}

xml：

/*        Caused by: org.apache.ibatis.builder.BuilderException: Error evaluating expression
        'cityName == @com.weather.weatherexpert.common.utils.CityClass@CityEnum.XINZHOU.getName'. Cause: org.apache.ibatis.ognl.OgnlException:
        Could not get static field CityEnum from class com.weather.weatherexpert.common.utils.CityClass [java.lang.NoSuchFieldException: CityEnum]*/
        <if test="cityName == @com.weather.weatherexpert.common.utils.CityClass@CityEnum.XINZHOU.getName"><!--wrong-->
            area_table
        </if>	

可见，直接定义的枚举类可以正常使用，在类中定义的枚举类这样使用会报错，可能方法还没有找到。

如下正确：

 <if test="cityName == @com.a.b.c.CityClass$CityEnum@XINZHOU.getName"><!--right-->
  name = #{username}
 </if>

Mybatis里使用枚举Enum判断

<if test="dtEnum == @com.xxx.xxx.TestTypeEnum@HOUR">
  DATE_FORMAT(TM,'%Y-%m-%d %H') as keyStr,
</if>

TestTypeEnum定义如下

• HOUR("hour"),
• DAY("day"),
• MONTH("month"),
• YEAR("year");

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。