인프런 커뮤니티 질문&답변

package hello.itemservice.web.basic;

import hello.itemservice.domain.item.Item;
import hello.itemservice.domain.item.ItemRepository;
import lombok.RequiredArgsConstructor;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;

import javax.annotation.PostConstruct;
import java.util.List;

@Controller
@RequestMapping("/basic/items")
@RequiredArgsConstructor
public class BasicItemController {
    private final ItemRepository itemRepository;
    @GetMapping
    public String items(Model model) {
        List<Item> items = itemRepository.findAll();
        model.addAttribute("items", items);
        return "basic/items";
    }

    @GetMapping("/{itemId}")
    public String item(@PathVariable Long itemId,Model model){
        Item item = itemRepository.findById(itemId);
        model.addAttribute(item);
        System.out.println("BasicItemController.item");
        return "basic/item";
    }

    /**
     * 테스트용 데이터 추가
     */
    @PostConstruct
    public void init() {
        itemRepository.save(new Item("testA", 10000, 10));
        itemRepository.save(new Item("testB", 20000, 20));
    }
}

경로도 제대로 하고 했는데도 지속적으로 Whitelabel Error Page 페이지가 나옵니다.. 콘솔창에도 따로 오류메세지나 아무 메세지도 안뜨는데 어떤걸 의심해봐야하나요?