Mybatis条件if test如何使用枚举值

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");

来源：https://programskills.blog.csdn.net/article/details/86490787