Validating and Iterating Indexed Array Payloads in Web Controllers

public record ItemEntry(String skuCode, int quantity) {}
 
public record BatchShipmentRequest(ItemEntry[] entries) {}
 
@RestController
@RequestMapping("/shipments")
public class ShipmentController {
 
    @PostMapping("/process-batch")
    public ResponseEntity<String> processShipment(@RequestBody BatchShipmentRequest request) {
        ItemEntry[] items = request.entries();
        if (items == null || items.length == 0) {
            return ResponseEntity.badRequest().body("Batch array cannot be empty");
        }
 
        int totalQuantity = 0;
        for (int i = 0; i < items.length; i++) {
            ItemEntry item = items[i];
            if (item.quantity() <= 0) {
                return ResponseEntity.unprocessableEntity().body("Invalid quantity at index " + i);
            }
            totalQuantity += item.quantity();
        }
 
        return ResponseEntity.ok("Processed " + items.length + " entries with " + totalQuantity + " total items");
    }
}