In this post under MapStruct I will show with example how to map two enums having different constant name.
For our example lets say you have to map below enum
Day
package package12;
public enum Day {
MONDAY,
TUESDAY,
WEDNESDAY,
THURSDAY,
FRIDAY,
SATURDAY,
SUNDAY;
}
to below enum
Week
package package12;
public enum Week {
WEEK_DAY,
WEEK_END;
}
We will create below mapper interface
package package12;
import org.mapstruct.Mapper;
import org.mapstruct.ValueMapping;
import org.mapstruct.ValueMappings;
@Mapper
public interface DayToWeekMapper {
@ValueMappings({
@ValueMapping(source = "MONDAY", target = "WEEK_DAY"),
@ValueMapping(source = "TUESDAY", target = "WEEK_DAY"),
@ValueMapping(source = "WEDNESDAY", target = "WEEK_DAY"),
@ValueMapping(source = "THURSDAY", target = "WEEK_DAY"),
@ValueMapping(source = "FRIDAY", target = "WEEK_DAY"),
@ValueMapping(source = "SATURDAY", target = "WEEK_END"),
@ValueMapping(source = "SUNDAY", target = "WEEK_END")
})
Week dayToWeekMapping(Day day);
}
In the above interface, using “@ValueMapping” annotation we are explicity setting each enum values from “Day” enum to “Week” enum values.
Enum values from “MONDAY” to “FRIDAY” are mapped to “WEEK_DAY”. Whereas “SATURDAY” and “SUNDAY” are mapped to “WEEK_END”.
Below is the main class that shows how to use the interface
Main class
package package12;
import org.mapstruct.factory.Mappers;
public class Example12 {
public static void main(String[] args) {
DayToWeekMapper dayToWeekMapper = Mappers.getMapper(DayToWeekMapper.class);
Week week = dayToWeekMapper.dayToWeekMapping(Day.MONDAY);
System.out.println(week);
week = dayToWeekMapper.dayToWeekMapping(Day.SATURDAY);
System.out.println(week);
}
}
In this way we can map two enums having different constant names.
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