MapStruct implementation is not working in Spring Boot Web Application

Question

I am a newbie to Spring Boot and MapStruct Tool.

Earlier, A Project(written by other team using these technologies) is not starting up. Then, I had made some changes in Mapper Abstract Class but now mapper object is coming as null on application startup.

Mapper Abstract Class:

@Mapper(componentModel = "spring")
public abstract class UserAndEmployeeMapper {

    public UserAndEmployeeMapper INSTANCE = Mappers.getMapper( UserAndEmployeeMapper.class );

    @Mapping(source = "username", target = "name")
    @Mapping(source = "ssn", target = "ssn", defaultValue = "xxxxxx" )
    @Mapping(target = "salary", constant = "34.67")
    @Mapping(target = "dob", dateFormat = "dd/MM/yyyy", constant = "10/12/2002")
    public abstract Employee mapToEmployee(User user);

    public abstract List<Employee> mapToEmployee(List<User> users);

    @Mapping(source = "name", target = "username")
    public abstract User mapToUser(Employee employee);

    public abstract List<User> mapToUser(List<Employee> employees);

}

LoginServiceImpl class

@Service("loginService")
public class LoginServiceImpl implements LoginService{

    private static final AtomicLong counter = new AtomicLong();

    @Autowired
    private EmployeeDao employeeDao;

    private UserAndEmployeeMapper userAndEmployeeMapper;
...

}

pom.xml

<build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>${maven.compiler.plugin.version}</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                    <annotationProcessorPaths>
                        <path>
                            <groupId>org.mapstruct</groupId>
                            <artifactId>mapstruct-processor</artifactId>
                            <version>${mapstruct.jdk8.version}</version>
                        </path>
                    </annotationProcessorPaths>
                </configuration>
            </plugin>
</build>

After I added @Autowired in LoginServiceImpl, application is not starting and following error log is showing

***************************
APPLICATION FAILED TO START
***************************

Description:

Field userAndEmployeeMapper in org.service.impl.LoginServiceImpl required a bean of type 'org.mapper.UserAndEmployeeMapper' that could not be found.


Action:

Consider defining a bean of type 'org.mapper.UserAndEmployeeMapper' in your configuration.

Any suggestions ?

Answer 1

Making abstract class as an interface worked for me.

public interface UserAndEmployeeMapper {