ItemRepository package com.jpabook.repository; import com.jpabook.domain.item.Item; import lombok.RequiredArgsConstructor; import org.springframework.stereotype.Repository; import javax.persistence.EntityManager; import java.util.List; @Repository @RequiredArgsConstructor public class ItemRepository { private final EntityManager em; public void save(Item item) { if(item.getId() == null) { em.per..