通过RestTemplate使用Spring分页响应时出现not present错误

HttpHeaders headers = new HttpHeaders();
headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
HttpEntity<String> entity = new HttpEntity<>(headers);

Map<String, Integer> params = new HashMap<>();
params.put("page", 0); // 设置当前页码
params.put("size", 10); // 设置每页大小

UriComponentsBuilder builder = UriComponentsBuilder.fromHttpUrl("http://example.com/api/items")
        .queryParams(params);

ResponseEntity<String> response = restTemplate.exchange(
        builder.toUriString(),
        HttpMethod.GET,
        entity,
        String.class);

Page<Item> page = new PageImpl<>(itemList, pageable, totalElements);

import org.springframework.http.*;
import org.springframework.web.client.RestTemplate;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageImpl;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Pageable;

import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class PaginationExample {

    public static void main(String[] args) {
        RestTemplate restTemplate = new RestTemplate();

        HttpHeaders headers = new HttpHeaders();
        headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
        HttpEntity<String> entity = new HttpEntity<>(headers);

        Map<String, Integer> params = new HashMap<>();
        params.put("page", 0);
        params.put("size", 10);

        UriComponentsBuilder builder = UriComponentsBuilder.fromHttpUrl("http://example.com/api/items")
                .queryParams(params);

        ResponseEntity<Item[]> response = restTemplate.exchange(
                builder.toUriString(),
                HttpMethod.GET,
                entity,
                Item[].class);

        Item[] items = response.getBody();
        Pageable pageable = PageRequest.of(params.get("page"), params.get("size"));
        Page<Item> page = new PageImpl<>(Arrays.asList(items), pageable, items.length);

        System.out.println("Total pages: " + page.getTotalPages());
        System.out.println("Total elements: " + page.getTotalElements());
        System.out.println("Current page elements: " + page.getContent());
    }
}

class Item {
    private String name;
    // getters and setters
}