SpringデータJPA

public interface MemberRepository extends JpaRepository<Member, Long> {}

public interface MemberRepository extends Repository<Member ,Long> {
	List<Member> findByEmailAndName(String email, String name);
}

select m from Member m where m.email =?1 and m.name =?2

// @NamedQuery 에노테이션으로 네임드 쿼리 정의

@Entity
@NamedQuery(
	name="Member.findByUsername"
	query="select m from Member m where m.username =  :username
)
public class Member {...}


// 스프링 데이터 JPA에서 네임드 쿼리 사용

public interface MemberRepository extends JpaRepository<Member, Long> { // 여기 선언한 Member 도메인 클래스

	List<Member> findByUsername(@Param("username") String username );
}

public interface MemberRepository extends JpaRepository<Member, Long> {
	@Query("select m from Member m where m.username = ?1")
    Member findByusername(String username);

// 네이티브 SQL 사용하려면  nativeQuery= true를 사용한다. 참고로 네이티브 SQL은 위치기반 파라미터가 0부터 시작한다.
	@Query(value ="SELECT * FROM MEMBER WHERE USERNAME = ?0 , nativeQuery= true) ;
	Member findByUsernameForNative(@Param("username") String username );
}

@Query("select m from Member m where m.username = :username")
Member findByUsernameForNative(@Param("username") String username );

@Modifying
@Query("update Product p set p.price =  p.price  * 1.1 where p.stockAmount < :stockAmount")
	int bulkPriceUp(@Param("stockAmount") String stockAmount);

Page<Member> findByName(String name , Pageable pageable); // count 쿼리 사용

List<Member> findByName(String name , Pageable pageable); // count 쿼리 x

List<Member> findByName(String name , Sort sort);

// 인터페이스 정의

## 힌트

```java
@QueryHints(value ={ @QueryHint(name = "org.hibernate.readOnly", value="true")}, forCounting = true)
Page<Member> findByName(String name , Pageable pageable);

public interface JpaSpecificationExecutor <T> {
	T findOne(Sepcification <T> spec);
    List<T> findAll(Sepcification<T> spec);
    Page<T> findAll(Sepcification<T> spec, Pageable pageable);
    List<T> findAll(Sepcification<T> spec, Sort sort);
    long count(Sepcification<T> secp);


public interface OrderRepository extends JpaRepository<Order,Long> , JpaSpecificationExecutor<Order> {
}

public List<Order> findOrders(String name) {
	List<Order> result = orderRepository.findAll(
    	where(memberName(name)).and(isOrderStatus())
   );
   
   return result;
)  

public interface MemberRepositoryCustom {
	public List<Member> findMemberCustom();
}

public class  MemberRepositoryCustomImpl implements MemberRepositoryCustom {
	public List<Member> findMemberCustom() {...}
}

public interface MemberRepository extends JpaRepository<Member, Long> , MemberRepositoryCustom {
}

// 도메인 클래스 ( 컨버터 기능 사용 x )
@Controller
public class MemberController {

@AutoWired
MemberRepository memberRepository;

@PostMapping("/member/updade")
public class memberUpdate(@RequestParam("id") Long id, Model model) {
	Member member = memberRepository.findOne(id);
		...
	}
}


// 도메인 클래스 ( 컨버터 기능 사용)
@Controller
public class MemberController {

@AutoWired
MemberRepository memberRepository;

@PostMapping("/member/updade")
public class memberUpdate(@RequestParam("id") Member member, Model model) {
    	soutv(member.getName());
	}
}

@RequestMapping(value ="/members")
public String list(Pageable pageable , Model model){
	Page<Member> page = memberService.findMember(pageable);

	model.addAttribute("members", page.getContent());

	return "member/memberList";
}

public String list(
	@Qualifier("member") Pageable memberPageable,
	@Qualifier("order") Pageable orderPageable), ...

@GetMapping("/members_page")
public String list(@PageableDefault(size=12, sort="name", direction=Sort.Direction.DESC) Pageable pageable){
	...
}

public interface ItemRepository extends JpaRepository<Item, Long>, QueryDslPredicateExecutor<Item> {}

// QueryDSL 사용예제
QItem item = Qitem.item;

Iterable<Item> result = itemRepository.findAll(
	item.name.contains("장난감").and(item.price.between(1000,2000))
);

public interface CustomOrderRepository {
	public List<Order> search(OrderSearch orderSearch);
}

public class CustomOrderRepositoryImpl extends QueryDslRepositorySupport implements CustomOrderRepository {
	public CustomOrderRepositoryImpl (){
		super(Order.class);
	}
    
    @Override
    public List<Order> search(OrderSearch orderSearch) {
    	QOrder order = QOrder.order;
        QMember member =QMember.member;
        
        JPQLQuery query = from(order);
        
        if(StringUtils.hasText(orderSearch.getMemberName())){
        	query.leftJoin(order.member, member)
            	.where(member.name.contains(orderSearch.getMemberName()));
		}
        
        if(orderSearch.getOrderStatus() != null ) {
        	query.where(order.staus.eq(orderSearch.getOrderStatus()));
		}
        
        return query.lisr(order);
	}
}