MapStruct - Mapping enum



Mapstruct automatically maps enums. Enums with same name are mapped automatically. In case of different name, we can use @ValueMapping annotation to do the mapping.

Syntax

@Mapper public interface UtilityMapper { @ValueMapping(source = "EXTRA", target = "SPECIAL") PlacedOrderType getEnum(OrderType order); }

Following example demonstrates the same.

Example - Mapping enum

Open project mapping as updated in Mapping Stream chapter in Eclipse.

Create OrderType.java with following code −

OrderType.java

package com.tutorialspoint.enums; public enum OrderType { EXTRA, NORMAL, STANDARD }

Create PlacedOrderType.java with following code −

PlacedOrderType.java

package com.tutorialspoint.enums; public enum PlacedOrderType { SPECIAL, NORMAL, STANDARD }

Update UtilityMapper.java with following code −

UtilityMapper.java

package com.tutorialspoint.mapper; import java.util.GregorianCalendar; import java.util.Map; import java.util.stream.Stream; import org.mapstruct.MapMapping; import org.mapstruct.Mapper; import org.mapstruct.ValueMapping; import com.tutorialspoint.enums.OrderType; import com.tutorialspoint.enums.PlacedOrderType; @Mapper public interface UtilityMapper { @MapMapping(valueDateFormat = "dd.MM.yyyy") Map<String, String> getMap(Map<Long, GregorianCalendar> source); Stream<String> getStream(Stream<Integer> source); @ValueMapping(source = "EXTRA", target = "SPECIAL") PlacedOrderType getEnum(OrderType order); }

Update UtilityMapperTest.java with following code −

UtilityMapperTest.java

package com.tutorialspoint.test; import static org.junit.jupiter.api.Assertions.assertEquals; import java.util.Arrays; import java.util.GregorianCalendar; import java.util.HashMap; import java.util.Map; import java.util.stream.Stream; import org.junit.jupiter.api.Test; import org.mapstruct.factory.Mappers; import com.tutorialspoint.enums.OrderType; import com.tutorialspoint.enums.PlacedOrderType; import com.tutorialspoint.mapper.UtilityMapper; public class UtilityMapperTest { private UtilityMapper utilityMapper=Mappers.getMapper(UtilityMapper.class); @Test public void testMapMapping() { Map<Long, GregorianCalendar> source = new HashMap<>(); source.put(1L, new GregorianCalendar(2015, 3, 5)); Map<String, String> target = utilityMapper.getMap(source); assertEquals("05.04.2015", target.get("1")); } @Test public void testGetStream() { Stream<Integer> numbers = Arrays.asList(1, 2, 3, 4).stream(); Stream<String> strings = utilityMapper.getStream(numbers); assertEquals(4, strings.count()); } @Test public void testGetEnum() { PlacedOrderType placedOrderType = utilityMapper.getEnum(OrderType.EXTRA); PlacedOrderType placedOrderType1 = utilityMapper.getEnum(OrderType.NORMAL); PlacedOrderType placedOrderType2 = utilityMapper.getEnum(OrderType.STANDARD); assertEquals(PlacedOrderType.SPECIAL.name(), placedOrderType.name()); assertEquals(PlacedOrderType.NORMAL.name(), placedOrderType1.name()); assertEquals(PlacedOrderType.STANDARD.name(), placedOrderType2.name()); } }

Run the following command to test the mappings.

mvn clean test

Output

Once command is successful. Verify the output.

mvn clean test
[INFO] Scanning for projects...
...
[INFO] -------------------------------------------------------
[INFO]  T E S T S
[INFO] -------------------------------------------------------
[INFO] Running com.tutorialspoint.test.[1mCarMapperTest[m
[INFO] [1;32mTests run: [0;1;32m1[m, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.115 s -- in com.tutorialspoint.test.[1mCarMapperTest[m
[INFO] Running com.tutorialspoint.test.[1mDeliveryAddressMapperTest[m
[INFO] [1;32mTests run: [0;1;32m1[m, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.007 s -- in com.tutorialspoint.test.[1mDeliveryAddressMapperTest[m
[INFO] Running com.tutorialspoint.test.[1mStudentMapperTest[m
[INFO] [1;32mTests run: [0;1;32m2[m, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.006 s -- in com.tutorialspoint.test.[1mStudentMapperTest[m
[INFO] Running com.tutorialspoint.test.[1mUtilityMapperTest[m
[INFO] [1;32mTests run: [0;1;32m3[m, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.016 s -- in com.tutorialspoint.test.[1mUtilityMapperTest[m
[INFO] 
[INFO] Results:
[INFO] 
[INFO] [1;32mTests run: 7, Failures: 0, Errors: 0, Skipped: 0[m
[INFO] 
[INFO] [1m------------------------------------------------------------------------[m
[INFO] [1;32mBUILD SUCCESS[m
[INFO] [1m------------------------------------------------------------------------[m
[INFO] Total time:  4.091 s
[INFO] Finished at: 2025-09-14T16:20:20+05:30
[INFO] [1m------------------------------------------------------------------------[m
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