[SB] 18. Search 검색

최재원

May 08, 2025

Contents

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DB에서 조회 시 like 연산자를 사용해 keyword가 포함된 데이터를 가져오면 된다

Search

board/list


{{> layout/header}}

<div class="container p-5">

    <div class="mb-3 d-flex justify-content-end">
        <form action="/" class="d-flex">
            <input class="form-control me-2" type="text" placeholder="검색..." name="keyword">
            <button class="btn btn-primary flex-shrink-0" type="submit">검색</button>
        </form>
    </div>

    {{#model.boards}}
        <div class="card mb-3">
            <div class="card-body">
                <div class="d-flex justify-content-between">
                    <h4 class="card-title mb-3">{{title}}</h4>
                    {{^isPublic}}
                        <div>
                            <span class="badge bg-secondary">비공개</span>
                        </div>
                    {{/isPublic}}
                </div>
                <a href="/board/{{id}}" class="btn btn-primary">상세보기</a>
            </div>
        </div>
    {{/model.boards}}

    <ul class="pagination d-flex justify-content-center">
        <li class="page-item {{#model.isFirst}}disabled{{/model.isFirst}}">
            <a class="page-link"
               href="?page={{model.prev}}&keyword={{model.keyword}}">Previous</a>
        </li>

        {{#model.numbers}}
            <li class="page-item"><a class="page-link" href="?page={{.}}&keyword={{model.keyword}}">{{.}}</a></li>
        {{/model.numbers}}

        <li class="page-item {{#model.isLast}}disabled{{/model.isLast}}">
            <a class="page-link" href="?page={{model.next}}&keyword={{model.keyword}}">Next</a>
        </li>
    </ul>

</div>

{{> layout/footer}}

빨간줄 → input의 값을 어느 key값으로 받을지 결정

BoardController


    @GetMapping("/")
    public String list(HttpServletRequest request,
                       @RequestParam(required = false, value = "page", defaultValue = "0") Integer page,
                       @RequestParam(required = false, value = "keyword", defaultValue = "") String keyword) {
        User sessionUser = (User) session.getAttribute("sessionUser");

        if (sessionUser == null) {
            request.setAttribute("model", boardService.목록보기(null, page, keyword));
        } else {
            request.setAttribute("model", boardService.목록보기(sessionUser.getId(), page, keyword));
        }

        return "board/list";
    }

required = false → null을 허용하겠다

/?keyword= → 이렇게 오면 공백
/ → 이렇게 오면 null 이다

defaultValue = "" → null 이 들어올때 기본값으로 공백을 설정

BoardService


    public BoardResponse.DTO 목록보기(Integer userId, Integer page, String keyword) {
        if (userId == null) {
//            return boardRepository.findAll(page);
            List<Board> boards = boardRepository.findAll(page, keyword);
            Long totalCount = boardRepository.totalCount(keyword);
            return new BoardResponse.DTO(boards, page, totalCount.intValue(), keyword);
        } else {
//            return boardRepository.findAll(userId, page);
            List<Board> boards = boardRepository.findAll(userId, page, keyword);
            Long totalCount = boardRepository.totalCount(userId, keyword);
            return new BoardResponse.DTO(boards, page, totalCount.intValue(), keyword);
        }
    }

Controller에서 받은 keword를 전달한다

BoardResponse


@Data
    public static class DTO {
        private List<Board> boards;
        private Integer current;
        private Integer next;
        private Integer prev;
        private Integer totalCount;
        private Integer size;
        private Integer totalPages;
        private Boolean isFirst; // currentPage를 알아야 한다
        private Boolean isLast; // totalCount, size=3, totalPage를 알아야 한다
        private List<Integer> numbers;
        private Integer pageSize;
        private String keyword; // null 이면 머스테치에서 터진다

        public DTO(List<Board> boards, Integer current, Integer totalCount, String keyword) {
            this.boards = boards;
            this.next = current + 1;
            this.prev = current - 1;
            this.current = current;
            this.totalCount = totalCount;
            this.size = 3;
            this.totalPages = makeTotalPages(totalCount, this.size);
            this.isFirst = current == 0;
            this.isLast = current == this.totalPages - 1;
            this.numbers = makeNumbers(current, this.totalPages);
            this.keyword = keyword;
        }

Controller에서 받은 keword를 전달한다

BoardRepository


    // locahost:8080?page=0
    public List<Board> findAll(int page, String keyword) {
        String sql;

        if (keyword.isBlank()) {
            sql = "select b from Board b where b.isPublic = true order by b.id desc";

        } else {
            sql = "select b from Board b where b.isPublic = true and b.title like :keyword order by b.id desc";
        }

        Query query = em.createQuery(sql, Board.class);
        if (!keyword.isBlank()) query.setParameter("keyword", "%" + keyword + "%");
        query.setFirstResult(page * 3);
        query.setMaxResults(3);

        return query.getResultList();
    }

    public List<Board> findAll(Integer userId, int page, String keyword) {
        String sql;
        if (keyword.isBlank()) {
            sql = "select b from Board b where b.isPublic = true or b.user.id = :userId order by b.id desc";
        } else {
            sql = "select b from Board b where b.isPublic = true or b.user.id = :userId and b.title like :keyword order by b.id desc";
        }

        Query query = em.createQuery(sql, Board.class);
        query.setParameter("userId", userId);
        if (!keyword.isBlank()) query.setParameter("keyword", "%" + keyword + "%");
        query.setFirstResult(page * 3);
        query.setMaxResults(3);

        return query.getResultList();
    }
    
    public Long totalCount(String keyword) {
        String sql;
        if (!(keyword.isBlank())) {
            sql = "select count(b) from Board b where b.isPublic = true and b.title like :keyword";
        } else {
            sql = "select count(b) from Board b where b.isPublic = true";
        }
        Query query = em.createQuery(sql, Long.class);
        // keyword를 포함 : title like %keyword%
        if (!(keyword.isBlank())) query.setParameter("keyword", "%" + keyword + "%");

        return (Long) query.getSingleResult();
    }

    public Long totalCount(int userId, String keyword) {
        String sql;
        if (!(keyword.isBlank())) {
            sql = "select count(b) from Board b where b.isPublic = true or b.user.id = :userId and b.title like :keyword";
        } else {
            sql = "select count(b) from Board b where b.isPublic = true or b.user.id = :userId";
        }
        Query query = em.createQuery(sql, Long.class);
        // keyword를 포함 : title like %keyword%
        if (!(keyword.isBlank())) query.setParameter("keyword", "%" + keyword + "%");
        query.setParameter("userId", userId);

        return (Long) query.getSingleResult();
    }

See more posts

[SB] 18. Search 검색

Search

board/list

BoardController

BoardService

BoardResponse

BoardRepository

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