Mapstruct quickstart

Maven pom.xml

    <properties>
        <org.mapstruct.version>1.3.0.Final</org.mapstruct.version>
    </properties>

    <dependency>
        <groupId>org.mapstruct</groupId>
        <artifactId>mapstruct</artifactId>
        <version>${org.mapstruct.version}</version>
    </dependency>

 <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-compiler-plugin</artifactId>
        <version>3.5.1</version> <!-- or newer version -->
        <configuration>
            <source>1.8</source>
            <target>1.8</target>
            <annotationProcessorPaths>
                <path>
                    <groupId>org.mapstruct</groupId>
                    <artifactId>mapstruct-processor</artifactId>
                    <version>${org.mapstruct.version}</version>
                </path>
                <!-- other annotation processors -->
            </annotationProcessorPaths>
        </configuration>
    </plugin>

Java

public class Car {
 
    private String make;
    private int numberOfSeats;
    private CarType type;
    
    public Car(String make, int numberOfSeats, CarType type) {
        super();
        this.make = make;
        this.numberOfSeats = numberOfSeats;
        this.type = type;
    }
    public String getMake() {
        return make;
    }
    public void setMake(String make) {
        this.make = make;
    }
    public int getNumberOfSeats() {
        return numberOfSeats;
    }
    public void setNumberOfSeats(int numberOfSeats) {
        this.numberOfSeats = numberOfSeats;
    }
    public CarType getType() {
        return type;
    }
    public void setType(CarType type) {
        this.type = type;
    }
}

public class CarDto {
 
    private String make;
    private int seatCount;
    private String type;
    public String getMake() {
        return make;
    }
    public void setMake(String make) {
        this.make = make;
    }
    public int getSeatCount() {
        return seatCount;
    }
    public void setSeatCount(int seatCount) {
        this.seatCount = seatCount;
    }
    public String getType() {
        return type;
    }
    public void setType(String type) {
        this.type = type;
    }
}

@Mapper
public interface CarMapper {
    CarMapper INSTANCE = Mappers.getMapper( CarMapper.class );
    
    @Mapping(source = "numberOfSeats", target = "seatCount")
    CarDto carToCarDto(Car car);
}

public enum CarType {
    SEDAN, HATCHBACK;
}

Test case

import static org.hamcrest.CoreMatchers.*;
import static org.junit.Assert.*;

import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;

class CarMapperTest {

    @BeforeEach
    void setUp() throws Exception {
    }

    @Test
    void test() {
        //given
        Car car = new Car( "Morris", 5, CarType.SEDAN );
     
        //when
        CarDto carDto = CarMapper.INSTANCE.carToCarDto( car );
     
        assertNotNull(carDto);
        assertThat(carDto.getMake(), is("Morris") );
        assertThat(carDto.getSeatCount(), is(5));
        assertThat(carDto.getType(), is("SEDAN"));
    }

}