Getting a Page of DTO objects from Spring Data repository

Question

I'm trying to use DTOs in a Spring project to decouple business and presentation but I'm having problems while retrieving data from the Spring Data repository. Here I have a sample code:

public Page<UserDto> findAll(int pageIndex) {
    return userRepository.findAll(createPageable(pageIndex)); // Page<User>
}

As you can see, I'm trying to return a page of UserDto but I'm getting a page of User.

How can I do this?

Answer 1

Since Spring-Data 1.10 you can use the Page#map function:

public Page<UserDto> findAll(Pageable p) {
    return userRepository.findAll(p).map(UserConverter::convert);
}

See Spring Data. The UserConverter#convert method takes a Person and converts it to PersonDto.

public PersonDto convert(Person person) {
    return new PersonDto(person.getXyz1(), person.getXyz2);
}

Answer 2

You can do it like this :

public Page<UserDto> findAll(Pageable p) {
    Page<User> page = userRepository.findAll(p); // Page<User>
    return new PageImpl<UserDto>(UserConverter.convert(page.getContent()), p, page.getTotalElements());
}