列出 Return Inventories（分頁）

import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.time.Instant;
import java.time.temporal.ChronoUnit;

// Requires a JSON library on the classpath. Below uses org.json for brevity:
//   <dependency><groupId>org.json</groupId><artifactId>json</artifactId></dependency>
import org.json.JSONArray;
import org.json.JSONObject;

class Main {
  static final String BASE_URL  = "https://api.returnhelpercentre.com/v1/user"; // production
  // sandbox: "https://api.returnshelper.com/uat/user"
  static final String API_KEY   = "<your api key>";
  static final String API_TOKEN = "<your api token>";

  static final int PAGE_SIZE   = 50;
  static final int WINDOW_DAYS = 62; // server cap: createTo.Date - createFrom.Date <= 62

  public static void main(String[] args) throws Exception {
    Instant historyStart = Instant.parse("2024-01-01T00:00:00Z"); // backfill anchor
    Instant windowEnd    = Instant.now();                         // walk backwards from now

    HttpClient http = HttpClient.newHttpClient();

    while (windowEnd.isAfter(historyStart)) {
      Instant windowStart = windowEnd.minus(WINDOW_DAYS, ChronoUnit.DAYS);
      if (windowStart.isBefore(historyStart)) {
        windowStart = historyStart;
      }

      int offset = 0;
      int total  = Integer.MAX_VALUE;

      while (offset < total) {
        String url = BASE_URL + "/api/ReturnInventory/list"
                   + "?pageSize="   + PAGE_SIZE
                   + "&offset="     + offset
                   + "&createFrom=" + windowStart
                   + "&createTo="   + windowEnd;

        HttpRequest req = HttpRequest.newBuilder()
            .uri(URI.create(url))
            .header("x-rr-apikey",   API_KEY)
            .header("x-rr-apitoken", API_TOKEN)
            .header("Accept",        "application/json")
            .GET()
            .build();

        HttpResponse<String> resp = http.send(req, HttpResponse.BodyHandlers.ofString());
        JSONObject body = new JSONObject(resp.body());

        // Standard envelope: business status is in meta.status, not HTTP status.
        JSONObject meta = body.optJSONObject("meta");
        if (meta == null || meta.optInt("status") != 200) {
          System.err.println("list call failed: " + (meta == null ? "no meta" : meta.toString()));
          return;
        }

        total = body.optInt("totalNumberOfRecords", 0);
        JSONArray rows = body.optJSONArray("data");
        if (rows != null) {
          for (int i = 0; i < rows.length(); i++) {
            JSONObject inv = rows.getJSONObject(i);
            // TODO: UPSERT into your DB with returnInventoryId as primary key.
            //       Adjacent windows share a seam day, so the same row may be
            //       returned twice; UPSERT absorbs the duplicate.
            //   inv.getLong("returnInventoryId")
            //   inv.getString("handlingCode")
            //   inv.getString("handlingStatusCode")
            //   inv.getInt("warehouseId")
          }
        }

        offset += PAGE_SIZE;
        Thread.sleep(200); // light throttle
      }

      windowEnd = windowStart;
    }
  }
}