How to map Page<ObjectEntity> to Page<ObjectDTO> in spring-data-rest

You can still use the Page.map without lambda expressions:

Page<ObjectEntity> entities = objectEntityRepository.findAll(pageable);
Page<ObjectDto> dtoPage = entities.map(new Converter<ObjectEntity, ObjectDto>() {
    @Override
    public ObjectDto convert(ObjectEntity entity) {
        ObjectDto dto = new ObjectDto();
        // Conversion logic

        return dto;
    }
});

In Spring Data 2, the Page map method takes a Function instead of a Converter, but it still works basically the same as @Ali Dehghani described.

Using Function:

Page<ObjectEntity> entities = objectEntityRepository.findAll(pageable);
Page<ObjectDto> dtoPage = entities.map(new Function<ObjectEntity, ObjectDto>() {
    @Override
    public ObjectDto apply(ObjectEntity entity) {
        ObjectDto dto = new ObjectDto();
        // Conversion logic

        return dto;
    }
});

And in java8:

Page<ObjectDto> entities = 
 objectEntityRepository.findAll(pageable)
 .map(ObjectDto::fromEntity);

Where fromEntity is a static method on ObjectDto that contains the conversion logic.