package com.baeldung.mapper; import org.mapstruct.Mapper; import org.mapstruct.Mapping; import org.mapstruct.factory.Mappers; import com.baeldung.dto.PersonDTO; import com.baeldung.entity.Person; @Mapper public interface PersonMapper { PersonMapper INSTANCE = Mappers.getMapper(PersonMapper.class); @Mapping(target = "id", source = "person.id", defaultExpression = "java(java.util.UUID.randomUUID().toString())") PersonDTO personToPersonDTO(Person person); }