Managing pagination through HTTP headers on Spring Boot. `PageResponseAdvice` intercepts responses in `PageResponse` type and puts pagination related fields into HTTP response headers.

PaginationThroughHttpHeadersResponseAdvice.java

@ControllerAdvice
public class PageResponseAdvice implements ResponseBodyAdvice<Object> {

    @Override
    public boolean supports(MethodParameter returnType, Class<? extends HttpMessageConverter<?>> converterType) {
        return PageResponse.class.isAssignableFrom(returnType.getParameterType());
    }

    @Override
    public Object beforeBodyWrite(Object body,
                                  MethodParameter returnType,
                                  MediaType selectedContentType,
                                  Class<? extends HttpMessageConverter<?>> selectedConverterType,
                                  ServerHttpRequest request,
                                  ServerHttpResponse response) {
        PageResponse pageResponse = (PageResponse) body;
        response.getHeaders().add("X-Paging-Page", String.valueOf(pageResponse.getPage()));
        response.getHeaders().add("X-Paging-Page-Size", String.valueOf(pageResponse.getPageSize()));
        response.getHeaders().add("X-Paging-Total-Page", String.valueOf(pageResponse.getTotalPage()));
        return pageResponse.getData();
    }
}

@RestController
@RequestMapping("/products")
public class ProductController {

    private final ProductService productService;

    @Autowired
    public ProductController(ProductService productService) {
        this.productService = productService;
    }

    @GetMapping
    public PageResponse<ProductResponse> getProducts(ProductFilterRequest productFilterRequest) {
        Page<ProductResponse> products = productService.getProducts(productFilterRequest);
        return new PageResponse<>(
          productFilterRequest.getPage(), 
          productFilterRequest.getPageSize(), 
          products.getTotalPages(), 
          products.getContent()
        );
    }
}

public class PageResponse<T> {

    private final Integer page;
    private final Integer pageSize;
    private final Integer totalPage;
    private final List<T> data;

    public PageResponse(Integer page, Integer pageSize, Integer totalPage, List<T> data) {
        this.page = page;
        this.pageSize = pageSize;
        this.totalPage = totalPage;
        this.data = data;
    }

    public Integer getPage() {
        return page;
    }

    public Integer getPageSize() {
        return pageSize;
    }

    public Integer getTotalPage() {
        return totalPage;
    }

    public List<T> getData() {
        return data;
    }
}