”;
Using Mapstruct we can map list in similar fashion as we map primitives. To get a list of objects, we should provide a mapper method which can map an object.
Syntax
@Mapper public interface CarMapper { List<String> getListOfStrings(List<Integer> listOfIntegers); List<Car> getCars(List<CarEntity> carEntities); Car getModelFromEntity(CarEntity carEntity); }
Following example demonstrates the same.
Example
Open project mapping as updated in Mapping Using defaultExpression chapter in Eclipse.
Update CarEntity.java with following code −
CarEntity.java
package com.tutorialspoint.entity; import java.util.GregorianCalendar; public class CarEntity { private int id; private double price; private GregorianCalendar manufacturingDate; private String name; public int getId() { return id; } public void setId(int id) { this.id = id; } public double getPrice() { return price; } public void setPrice(double price) { this.price = price; } public GregorianCalendar getManufacturingDate() { return manufacturingDate; } public void setManufacturingDate(GregorianCalendar manufacturingDate) { this.manufacturingDate = manufacturingDate; } public String getName() { return name; } public void setName(String name) { this.name = name; } }
Update Car.java with following code −
Car.java
package com.tutorialspoint.model; public class Car { private int id; private String price; private String manufacturingDate; private String brand; private String name; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getPrice() { return price; } public void setPrice(String price) { this.price = price; } public String getManufacturingDate() { return manufacturingDate; } public void setManufacturingDate(String manufacturingDate) { this.manufacturingDate = manufacturingDate; } public String getBrand() { return brand; } public void setBrand(String brand) { this.brand = brand; } public String getName() { return name; } public void setName(String name) { this.name = name; } }
Update CarMapper.java with following code −
CarMapper.java
package com.tutorialspoint.mapper; import org.mapstruct.Mapper; import org.mapstruct.Mapping; import com.tutorialspoint.entity.CarEntity; import com.tutorialspoint.model.Car; import java.util.List; import java.util.UUID; @Mapper( imports = UUID.class ) public interface CarMapper { @Mapping(source = "name", target = "name", defaultExpression = "java(UUID.randomUUID().toString())") @Mapping(target = "brand", constant = "BMW") @Mapping(source = "price", target = "price", numberFormat = "$#.00") @Mapping(source = "manufacturingDate", target = "manufacturingDate", dateFormat = "dd.MM.yyyy") Car getModelFromEntity(CarEntity carEntity); List<String> getListOfStrings(List<Integer> listOfIntegers); List<Car> getCars(List<CarEntity> carEntities); }
Update CarMapperTest.java with following code −
CarMapperTest.java
package com.tutorialspoint.mapping; import static org.junit.jupiter.api.Assertions.assertEquals; import static org.junit.jupiter.api.Assertions.assertNotNull; import java.util.Arrays; import java.util.GregorianCalendar; import java.util.List; import org.junit.jupiter.api.Test; import org.mapstruct.factory.Mappers; import com.tutorialspoint.entity.CarEntity; import com.tutorialspoint.mapper.CarMapper; import com.tutorialspoint.model.Car; public class CarMapperTest { private CarMapper carMapper = Mappers.getMapper(CarMapper.class); @Test public void testEntityToModel() { CarEntity entity = new CarEntity(); entity.setPrice(345000); entity.setId(1); entity.setManufacturingDate(new GregorianCalendar(2015, 3, 5)); CarEntity entity1 = new CarEntity(); entity1.setPrice(445000); entity1.setId(2); entity1.setManufacturingDate(new GregorianCalendar(2015, 3, 5)); List<CarEntity> carEntities = Arrays.asList(entity, entity1); Car model = carMapper.getModelFromEntity(entity); assertEquals("$345000.00",model.getPrice()); assertEquals(entity.getId(), model.getId()); assertEquals("BMW", model.getBrand()); assertEquals("05.04.2015", model.getManufacturingDate()); List<Integer> list = Arrays.asList(1,2,3); List<String> listOfStrings = carMapper.getListOfStrings(list); List<Car> listOfCars = carMapper.getCars(carEntities); assertEquals(3, listOfStrings.size()); assertEquals(2, listOfCars.size()); } }
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] --- maven-surefire-plugin:2.12.4:test (default-test) @ mapping --- [INFO] Surefire report directory: mvnmappingtargetsurefire-reports ------------------------------------------------------- T E S T S ------------------------------------------------------- Running com.tutorialspoint.mapping.CarMapperTest Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.035 sec Running com.tutorialspoint.mapping.DeliveryAddressMapperTest Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0 sec Running com.tutorialspoint.mapping.StudentMapperTest Tests run: 2, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.001 sec Results : Tests run: 4, Failures: 0, Errors: 0, Skipped: 0 ...
Advertisements
”;